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Sync up with Linus #47

Merged
merged 150 commits into from
Mar 4, 2015
Merged

Sync up with Linus #47

merged 150 commits into from
Mar 4, 2015

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dabrace
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@dabrace dabrace commented Mar 4, 2015

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Jammy Zhou and others added 30 commits January 22, 2015 11:27
When the timeout value passed to reservation_object_wait_timeout_rcu
is zero, no wait should be done if the fences are not signaled.

Return '1' for idle and '0' for busy if the specified timeout is '0'
to keep consistent with the case of non-zero timeout.

v2: call fence_put if not signaled in the case of timeout==0

v3: switch to reservation_object_test_signaled_rcu

Signed-off-by: Jammy Zhou <[email protected]>
Reviewed-by: Christian König <[email protected]>
Reviewed-by: Alex Deucher <[email protected]>
Reviewed-By: Maarten Lankhorst <[email protected]>
Signed-off-by: Sumit Semwal <[email protected]>
When specified timeout is zero for fence_wait_timeout, just check if the fence
is signaled or not without wait.

Signed-off-by: Jammy Zhou <[email protected]>
Reviewed-by: Christian König <[email protected]>
Reviewed-By: Maarten Lankhorst <[email protected]>
Signed-off-by: Sumit Semwal <[email protected]>
It was causing the return value of fence_is_signaled to be ignored, making
reservation objects signal too early.

Cc: [email protected]
Reviewed-by: Maarten Lankhorst <[email protected]>
Reviewed-by: Alex Deucher <[email protected]>
Signed-off-by: Michel Dänzer <[email protected]>
Signed-off-by: Sumit Semwal <[email protected]>
The current code prevents any operation with a mixed-family dest
unless IP_VS_CONN_F_TUNNEL flag is set. The problem is that it's impossible
for the client to follow this rule, because ip_vs_genl_parse_dest does
not even read the destination conn_flags when cmd = IPVS_CMD_DEL_DEST
(need_full_dest = 0).

Also, not every client can pass this flag when removing a dest. ipvsadm,
for example, does not support the "-i" command line option together with
the "-d" option.

This change disables any checks for mixed-family on IPVS_CMD_DEL_DEST command.

Signed-off-by: Alexey Andriyanov <[email protected]>
Fixes: bc18d37 ("ipvs: Allow heterogeneous pools now that we support them")
Acked-by: Julian Anastasov <[email protected]>
Signed-off-by: Simon Horman <[email protected]>
Feb 12 18:20:42 nfdev kernel: ------------[ cut here ]------------
Feb 12 18:20:42 nfdev kernel: WARNING: CPU: 4 PID: 4359 at kernel/module.c:963 module_put+0x9b/0xba()
Feb 12 18:20:42 nfdev kernel: CPU: 4 PID: 4359 Comm: ebtables-compat Tainted: G        W      3.19.0-rc6+ #43
[...]
Feb 12 18:20:42 nfdev kernel: Call Trace:
Feb 12 18:20:42 nfdev kernel: [<ffffffff815fd911>] dump_stack+0x4c/0x65
Feb 12 18:20:42 nfdev kernel: [<ffffffff8103e6f7>] warn_slowpath_common+0x9c/0xb6
Feb 12 18:20:42 nfdev kernel: [<ffffffff8109919f>] ? module_put+0x9b/0xba
Feb 12 18:20:42 nfdev kernel: [<ffffffff8103e726>] warn_slowpath_null+0x15/0x17
Feb 12 18:20:42 nfdev kernel: [<ffffffff8109919f>] module_put+0x9b/0xba
Feb 12 18:20:42 nfdev kernel: [<ffffffff813ecf7c>] nft_match_destroy+0x45/0x4c
Feb 12 18:20:42 nfdev kernel: [<ffffffff813e683f>] nf_tables_rule_destroy+0x28/0x70

Reported-by: Arturo Borrero Gonzalez <[email protected]>
Signed-off-by: Pablo Neira Ayuso <[email protected]>
Tested-by: Arturo Borrero Gonzalez <[email protected]>
… max

given:
-A INPUT -m recent --update --seconds 30 --hitcount 4
and
iptables-save > foo

then
iptables-restore < foo

will fail with:
kernel: xt_recent: hitcount (4) is larger than packets to be remembered (4) for table DEFAULT

Even when the check is fixed, the restore won't work if the hitcount is
increased to e.g. 6, since by the time checkentry runs it will find the
'old' incarnation of the table.

We can avoid this by increasing the maximum threshold silently; we only
have to rm all the current entries of the table (these entries would
not have enough room to handle the increased hitcount).

This even makes (not-very-useful)
-A INPUT -m recent --update --seconds 30 --hitcount 4
-A INPUT -m recent --update --seconds 30 --hitcount 42
work.

Fixes: abc86d0 (netfilter: xt_recent: relax ip_pkt_list_tot restrictions)
Tracked-down-by: Chris Vine <[email protected]>
Signed-off-by: Florian Westphal <[email protected]>
Signed-off-by: Pablo Neira Ayuso <[email protected]>
As soon as extract_icmp6_fields() returns, its local storage (automatic
variables) is deallocated and can be overwritten.

Lets add an additional parameter to make sure storage is valid long
enough.

While we are at it, adds some const qualifiers.

Signed-off-by: Eric Dumazet <[email protected]>
Fixes: b64c925 ("tproxy: added IPv6 support to the socket match")
Signed-off-by: Pablo Neira Ayuso <[email protected]>
Our UC-KLEE tool found a kernel memory leak of 512 bytes (on x86_64) for
each call to gssp_accept_sec_context_upcall()
(net/sunrpc/auth_gss/gss_rpc_upcall.c). Since it appears that this call
can be triggered by remote connections (at least, from a cursory a
glance at the call chain), it may be exploitable to cause kernel memory
exhaustion. We found the bug in kernel 3.16.3, but it appears to date
back to commit 9dfd87d (2013-08-20).

The gssp_accept_sec_context_upcall() function performs a pair of calls
to gssp_alloc_receive_pages() and gssp_free_receive_pages().  The first
allocates memory for arg->pages.  The second then frees the pages
pointed to by the arg->pages array, but not the array itself.

Reported-by: David A. Ramos <[email protected]>
Fixes: 9dfd87d ("rpc: fix huge kmalloc's in gss-proxy”)
Signed-off-by: David A. Ramos <[email protected]>
Signed-off-by: J. Bruce Fields <[email protected]>
The gnet_stats_copy_app() function gets called, more often than not, with its
second argument a pointer to an automatic variable in the caller's stack.
Therefore, to avoid copying garbage afterwards when calling
gnet_stats_finish_copy(), this data is better copied to a dynamically allocated
memory that gets freed after use.

[[email protected]: remove a useless kfree()]

Signed-off-by: Ignacy Gawędzki <[email protected]>
Signed-off-by: Cong Wang <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
ehea creates memory hotplug, reboot and crash hooks even if there
are no adapters in the box. Just create them when we probe our
first adapter.

[cascardo: use ehea_register_memory_hooks return code]
Signed-off-by: Anton Blanchard <[email protected]>
Tested-by: Thadeu Lima de Souza Cascardo <[email protected]>
Signed-off-by: Thadeu Lima de Souza Cascardo <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
The National Instruments USB Host-to-Host Cable is based on the Prolific
PL-25A1 chipset.  Add its VID/PID so the plusb driver will recognize it.

Signed-off-by: Ben Shelton <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
…_bits

skb_copy_bits() returns zero on success and negative value on error,
so it is needed to invert the condition in ip_check_defrag().

Fixes: 1bf3751 ("ipv4: ip_check_defrag must not modify skb before unsharing")
Signed-off-by: Alexander Drozdov <[email protected]>
Acked-by: Eric Dumazet <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
phy_init_eee uses phy_find_setting(phydev->speed, phydev->duplex)
to find a valid entry in the settings array for the given speed
and duplex value. For full duplex 1000baseT, this will return
the first matching entry, which is the entry for 1000baseKX_Full.

If the phy eee does not support 1000baseKX_Full, this entry will not
match, causing phy_init_eee to fail for no good reason.

Fixes: 9a9c56c ("net: phy: fix a bug when verify the EEE support")
Fixes: 3e70770 ("phy: Expand phy speed/duplex settings array")
Cc: Giuseppe Cavallaro <[email protected]>
Signed-off-by: Guenter Roeck <[email protected]>
Acked-by: Florian Fainelli <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
In tcf_em_validate(), after calling request_module() to load the
kind-specific module, set em->ops to NULL before returning -EAGAIN, so
that module_put() is not called again by tcf_em_tree_destroy().

Signed-off-by: Ignacy Gawędzki <[email protected]>
Acked-by: Cong Wang <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Open vSwitch allows moving internal vport to different namespace
while still connected to the bridge. But when namespace deleted
OVS does not detach these vports, that results in dangling
pointer to netdevice which causes kernel panic as follows.
This issue is fixed by detaching all ovs ports from the deleted
namespace at net-exit.

BUG: unable to handle kernel NULL pointer dereference at 0000000000000028
IP: [<ffffffffa0aadaa5>] ovs_vport_locate+0x35/0x80 [openvswitch]
Oops: 0000 [#1] SMP
Call Trace:
 [<ffffffffa0aa6391>] lookup_vport+0x21/0xd0 [openvswitch]
 [<ffffffffa0aa65f9>] ovs_vport_cmd_get+0x59/0xf0 [openvswitch]
 [<ffffffff8167e07c>] genl_family_rcv_msg+0x1bc/0x3e0
 [<ffffffff8167e319>] genl_rcv_msg+0x79/0xc0
 [<ffffffff8167d919>] netlink_rcv_skb+0xb9/0xe0
 [<ffffffff8167deac>] genl_rcv+0x2c/0x40
 [<ffffffff8167cffd>] netlink_unicast+0x12d/0x1c0
 [<ffffffff8167d3da>] netlink_sendmsg+0x34a/0x6b0
 [<ffffffff8162e140>] sock_sendmsg+0xa0/0xe0
 [<ffffffff8162e5e8>] ___sys_sendmsg+0x408/0x420
 [<ffffffff8162f541>] __sys_sendmsg+0x51/0x90
 [<ffffffff8162f592>] SyS_sendmsg+0x12/0x20
 [<ffffffff81764ee9>] system_call_fastpath+0x12/0x17

Reported-by: Assaf Muller <[email protected]>
Fixes: 46df7b8("openvswitch: Add support for network namespaces.")
Signed-off-by: Pravin B Shelar <[email protected]>
Reviewed-by: Thomas Graf <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
If both promisc and allmulti are set, promisc should trump allmulti and
disable the MAC filter; otherwise, the interface is not really promisc.

Previously, this code checked IFF_ALLMULTI prior to and without regard for
IFF_PROMISC; if both were set, only multicast and direct unicast traffic
would make it through the filter.

Signed-off-by: Derrick Pallas <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
skb_gro_remcsum_init() initializes the gro_remcsum.delta member only,
leading to compiler warnings about a possibly uninitialized
gro_remcsum.offset member:

drivers/net/vxlan.c: In function ‘vxlan_gro_receive’:
drivers/net/vxlan.c:602: warning: ‘grc.offset’ may be used uninitialized in this function
net/ipv4/fou.c: In function ‘gue_gro_receive’:
net/ipv4/fou.c:262: warning: ‘grc.offset’ may be used uninitialized in this function

While these are harmless for now:
  - skb_gro_remcsum_process() sets offset before changing delta,
  - skb_gro_remcsum_cleanup() checks if delta is non-zero before
    accessing offset,
it's safer to let the initialization function initialize all members.

Signed-off-by: Geert Uytterhoeven <[email protected]>
Acked-by: Tom Herbert <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Non NAPI drivers can call skb_tstamp_tx() and then sock_queue_err_skb()
from hard IRQ context.

Therefore, sock_dequeue_err_skb() needs to block hard irq or
corruptions or hangs can happen.

Signed-off-by: Eric Dumazet <[email protected]>
Fixes: 364a9e9 ("sock: deduplicate errqueue dequeue")
Fixes: cb820f8 ("net: Provide a generic socket error queue delivery method for Tx time stamps.")
Signed-off-by: David S. Miller <[email protected]>
The smc91x driver tries to support multiple platforms at compile
time, but they are mutually exclusive at runtime, and not clearly
defined.

Trying to build for CONFIG_SA1100_ASSABET without CONFIG_ASSABET_NEPONSET
results in this link error:

drivers/built-in.o: In function `smc_drv_probe':
:(.text+0x33310c): undefined reference to `neponset_ncr_frob'

since the neponset_ncr_set function is not defined otherwise.

Similarly, building for both CONFIG_SA1100_ASSABET and CONFIG_SA1100_PLEB
results in a different build error:

smsc/smc91x.c: In function 'smc_drv_probe':
smsc/smc91x.c:2299:2: error: implicit declaration of function 'neponset_ncr_set' [-Werror=implicit-function-declaration]
  neponset_ncr_set(NCR_ENET_OSC_EN);
  ^
smsc/smc91x.c:2299:19: error: 'NCR_ENET_OSC_EN' undeclared (first use in this function)
  neponset_ncr_set(NCR_ENET_OSC_EN);
                   ^

This is an attempt to fix the call site responsible for both
errors, making sure we call the function exactly when the driver
is actually trying to run on the assabet/neponset machine. With
this patch, I no longer see randconfig build errors in this file.

Signed-off-by: Arnd Bergmann <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
The ltpc driver is rather outdated and does not get built on most
platforms because it requires the ISA_DMA_API symbol. However
there are some ARM platforms that have ISA_DMA_API but no virt_to_bus,
and they get this build error when enabling the ltpc driver.

drivers/net/appletalk/ltpc.c: In function 'handlefc':
drivers/net/appletalk/ltpc.c:380:2: error: implicit declaration of function 'virt_to_bus' [-Werror=implicit-function-declaration]
  set_dma_addr(dma,virt_to_bus(ltdmacbuf));
  ^

This adds another dependency in Kconfig to avoid that configuration.

Signed-off-by: Arnd Bergmann <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
With object runtime debugging enabled, the rhashtable test suite
will rightfully throw a warning "ODEBUG: object is on stack, but
not annotated" from rhashtable_init().

This is because run_work is (correctly) being initialized via
INIT_WORK(), and not annotated by INIT_WORK_ONSTACK(). Meaning,
rhashtable_init() is okay as is, we just need to move ht e.g.,
into global scope.

It never triggered anything, since test_rhashtable is rather a
controlled environment and effectively runs to completion, so
that stack memory is not vanishing underneath us, we shouldn't
confuse any testers with it though.

Fixes: 7e1e776 ("lib: Resizable, Scalable, Concurrent Hash Table")
Signed-off-by: Daniel Borkmann <[email protected]>
Acked-by: Thomas Graf <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
ipvlan was added into 3.19 release and iproute2 added support
for the same in iproute2-3.19 package.

Signed-off-by: Mahesh Bandewar <[email protected]>
CC: Stephen Hemminger <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
commit aafb3e9 (netdev: introduce new NETIF_F_HW_SWITCH_OFFLOAD feature
flag for switch device offloads) add a new feature without adding it to
netdev_features_strings array; this patch fixes this.

Signed-off-by: Rami Rosen <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Issue caught by 0-day kernel test infrastructure. Code changed to use sockaddr
members so that %pISc can be used instead.

Fixes: b5a02f5 ('cxgb4 : Update ipv6 address handling api')

Signed-off-by: Anish Bhatt <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
The cfpkt_iterate() function can return -EPROTO on error, but the
function is a u16 so the negative value gets truncated to a positive
unsigned short.  This causes a static checker warning.

The only caller which might care is cffrml_receive(), when it's checking
the frame checksum.  I modified cffrml_receive() so that it never says
-EPROTO is a valid checksum.

Also this isn't ever going to be inlined so I removed the "inline".

Signed-off-by: Dan Carpenter <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Pablo Neira Ayuso says:

====================
Netfilter/IPVS fixes for net

The following patchset contains updates for your net tree, they are:

1) Fix removal of destination in IPVS when the new mixed family support
   is used, from Alexey Andriyanov via Simon Horman.

2) Fix module refcount undeflow in nft_compat when reusing a match /
   target.

3) Fix iptables-restore when the recent match is used with a new hitcount
   that exceeds threshold, from Florian Westphal.

4) Fix stack corruption in xt_socket due to using stack storage to save
   the inner IPv6 header, from Eric Dumazet.

I'll follow up soon with another batch with more fixes that are still
cooking.
====================

Signed-off-by: David S. Miller <[email protected]>
Restore pre 54c5b7d behaviour and only probe for expansions on inserts
and shrinks on deletes. Currently, it will happen that on initial inserts
into a sparse hash table, we may i.e. shrink it first simply because it's
not fully populated yet, only to later realize that we need to grow again.

This however is counter intuitive, e.g. an initial default size of 64
elements is already small enough, and in case an elements size hint is given
to the hash table by a user, we should avoid unnecessary expansion steps,
so a shrink is clearly unintended here.

Fixes: 54c5b7d ("rhashtable: introduce rhashtable_wakeup_worker helper function")
Signed-off-by: Daniel Borkmann <[email protected]>
Cc: Ying Xue <[email protected]>
Acked-by: Thomas Graf <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
When trying to allocate future tables via bucket_table_alloc(), it seems
overkill on large table shifts that we probe for kzalloc() unconditionally
first, as it's likely to fail.

Only probe with kzalloc() for more reasonable table sizes and use vzalloc()
either as a fallback on failure or directly in case of large table sizes.

Fixes: 7e1e776 ("lib: Resizable, Scalable, Concurrent Hash Table")
Signed-off-by: Daniel Borkmann <[email protected]>
Acked-by: Thomas Graf <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
There's no good reason why to disallow unloading of the rhashtable
test case module.

Commit 9d6dbe1 moved the code from a boot test into a stand-alone
module, but only converted the subsys_initcall() handler into a
module_init() function without a related exit handler, and thus
preventing the test module from unloading.

Fixes: 9d6dbe1 ("rhashtable: Make selftest modular")
Signed-off-by: Daniel Borkmann <[email protected]>
Acked-by: Thomas Graf <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Reading 64-bits register was not working because we inverted the steps
between reading the lower 32-bits of the register and reading the upper
32-bits. Swapping these operations is how the HW guarantees that 64-bits
reads are latched correctly. We only have a handful of 64-bits registers
for now, mostly MIB counters, so the imapct is low.

Fixes: 246d7f7 ("net: dsa: add Broadcom SF2 switch driver")
Signed-off-by: Florian Fainelli <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
mkubecek and others added 13 commits March 2, 2015 22:19
If an over-MTU UDP datagram is sent through a SOCK_RAW socket to a
UFO-capable device, ip_ufo_append_data() sets skb->ip_summed to
CHECKSUM_PARTIAL unconditionally as all GSO code assumes transport layer
checksum is to be computed on segmentation. However, in this case,
skb->csum_start and skb->csum_offset are never set as raw socket
transmit path bypasses udp_send_skb() where they are usually set. As a
result, driver may access invalid memory when trying to calculate the
checksum and store the result (as observed in virtio_net driver).

Moreover, the very idea of modifying the userspace provided UDP header
is IMHO against raw socket semantics (I wasn't able to find a document
clearly stating this or the opposite, though). And while allowing
CHECKSUM_NONE in the UFO case would be more efficient, it would be a bit
too intrusive change just to handle a corner case like this. Therefore
disallowing UFO for packets from SOCK_DGRAM seems to be the best option.

Signed-off-by: Michal Kubecek <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
make build fail if structure no longer fits into ->cb storage.

Signed-off-by: Florian Westphal <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Add a function that will enable changing the MAC address
of an ibmveth interface while it is still running.

Signed-off-by: Thomas Falcon <[email protected]>
Reviewed-by: Jiri Pirko <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Commit 6ce29b0 ("gianfar: Avoid unnecessary reg accesses in adjust_link()")
eliminates unnecessary calls to adjust_link for phy devices which don't support
interrupts and need polling. As part of that work, the 'new_state' local flag,
which was used to reduce logging noise on the console, was eliminated.

Unfortunately, that means that a 'Link is Down' log message will now be
issued continuously if a link is configured as UP, the link state is down,
and the associated phy requires polling. This occurs because priv->oldduplex
is -1 in this case, which always differs from phydev->duplex. In addition,
phydev->speed may also differ from priv->oldspeed.  gfar_update_link_state()
is therefore called each time a phy is polled, even if the link state did not
change.

Cc: Claudiu Manoil <[email protected]>
Signed-off-by: Guenter Roeck <[email protected]>
Reviewed-by: Claudiu Manoil <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Set actions consist of a regular OVS_KEY_ATTR_* attribute nested inside
of a OVS_ACTION_ATTR_SET action attribute. When converting masked actions
back to regular set actions, the inner attribute length was not changed,
ie, double the length being serialized. This patch fixes the bug.

Fixes: 83d2b9b ("net: openvswitch: Support masked set actions.")
Signed-off-by: Joe Stringer <[email protected]>
Acked-by: Jarno Rajahalme <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Pull networking fixes from David Miller:

 1) If an IPVS tunnel is created with a mixed-family destination
    address, it cannot be removed.  Fix from Alexey Andriyanov.

 2) Fix module refcount underflow in netfilter's nft_compat, from Pablo
    Neira Ayuso.

 3) Generic statistics infrastructure can reference variables sitting on
    a released function stack, therefore use dynamic allocation always.
    Fix from Ignacy Gawędzki.

 4) skb_copy_bits() return value test is inverted in ip_check_defrag().

 5) Fix network namespace exit in openvswitch, we have to release all of
    the per-net vports.  From Pravin B Shelar.

 6) Fix signedness bug in CAIF's cfpkt_iterate(), from Dan Carpenter.

 7) Fix rhashtable grow/shrink behavior, only expand during inserts and
    shrink during deletes.  From Daniel Borkmann.

 8) Netdevice names with semicolons should never be allowed, because
    they serve as a separator.  From Matthew Thode.

 9) Use {,__}set_current_state() where appropriate, from Fabian
    Frederick.

10) Revert byte queue limits support in r8169 driver, it's causing
    regressions we can't figure out.

11) tcp_should_expand_sndbuf() erroneously uses tp->packets_out to
    measure packets in flight, properly use tcp_packets_in_flight()
    instead.  From Neal Cardwell.

12) Fix accidental removal of support for bluetooth in CSR based Intel
    wireless cards.  From Marcel Holtmann.

13) We accidently added a behavioral change between native and compat
    tasks, wrt testing the MSG_CMSG_COMPAT bit.  Just ignore it if the
    user happened to set it in a native binary as that was always the
    behavior we had.  From Catalin Marinas.

14) Check genlmsg_unicast() return valud in hwsim netlink tx frame
    handling, from Bob Copeland.

15) Fix stale ->radar_required setting in mac80211 that can prevent
    starting new scans, from Eliad Peller.

16) Fix memory leak in nl80211 monitor, from Johannes Berg.

17) Fix race in TX index handling in xen-netback, from David Vrabel.

18) Don't enable interrupts in amx-xgbe driver until all software et al.
    state is ready for the interrupt handler to run.  From Thomas
    Lendacky.

19) Add missing netlink_ns_capable() checks to rtnl_newlink(), from Eric
    W Biederman.

20) The amount of header space needed in macvtap was not calculated
    properly, fix it otherwise we splat past the beginning of the
    packet.  From Eric Dumazet.

21) Fix bcmgenet TCP TX perf regression, from Jaedon Shin.

22) Don't raw initialize or mod timers, use setup_timer() and
    mod_timer() instead.  From Vaishali Thakkar.

23) Fix software maintained statistics in bcmgenet and systemport
    drivers, from Florian Fainelli.

24) DMA descriptor updates in sh_eth need proper memory barriers, from
    Ben Hutchings.

25) Don't do UDP Fragmentation Offload on RAW sockets, from Michal
    Kubecek.

26) Openvswitch's non-masked set actions aren't constructed properly
    into netlink messages, fix from Joe Stringer.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (116 commits)
  openvswitch: Fix serialization of non-masked set actions.
  gianfar: Reduce logging noise seen due to phy polling if link is down
  ibmveth: Add function to enable live MAC address changes
  net: bridge: add compile-time assert for cb struct size
  udp: only allow UFO for packets from SOCK_DGRAM sockets
  sh_eth: Really fix padding of short frames on TX
  Revert "sh_eth: Enable Rx descriptor word 0 shift for r8a7790"
  sh_eth: Fix RX recovery on R-Car in case of RX ring underrun
  sh_eth: Ensure proper ordering of descriptor active bit write/read
  net/mlx4_en: Disbale GRO for incoming loopback/selftest packets
  net/mlx4_core: Fix wrong mask and error flow for the update-qp command
  net: systemport: fix software maintained statistics
  net: bcmgenet: fix software maintained statistics
  rxrpc: don't multiply with HZ twice
  rxrpc: terminate retrans loop when sending of skb fails
  net/hsr: Fix NULL pointer dereference and refcnt bugs when deleting a HSR interface.
  net: pasemi: Use setup_timer and mod_timer
  net: stmmac: Use setup_timer and mod_timer
  net: 8390: axnet_cs: Use setup_timer and mod_timer
  net: 8390: pcnet_cs: Use setup_timer and mod_timer
  ...
Pull nfsd fixes from Bruce Fields:
 "Three miscellaneous bugfixes, most importantly the clp->cl_revoked
  bug, which we've seen several reports of people hitting"

* 'for-4.0' of git://linux-nfs.org/~bfields/linux:
  sunrpc: integer underflow in rsc_parse()
  nfsd: fix clp->cl_revoked list deletion causing softlock in nfsd
  svcrpc: fix memory leak in gssp_accept_sec_context_upcall
Anton has a busy ppc64le KVM box where guests sometimes hit the infamous
"kernel BUG at kernel/smpboot.c:134!" issue during boot:

  BUG_ON(td->cpu != smp_processor_id());

Basically a per CPU hotplug thread scheduled on the wrong CPU. The oops
output confirms it:

  CPU: 0
  Comm: watchdog/130

The problem is that we aren't ensuring the CPU active bit is set for the
secondary before allowing the master to continue on. The master unparks
the secondary CPU's kthreads and the scheduler looks for a CPU to run
on. It calls select_task_rq() and realises the suggested CPU is not in
the cpus_allowed mask. It then ends up in select_fallback_rq(), and
since the active bit isnt't set we choose some other CPU to run on.

This seems to have been introduced by 6acbfb9 "sched: Fix hotplug
vs. set_cpus_allowed_ptr()", which changed from setting active before
online to setting active after online. However that was in turn fixing a
bug where other code assumed an active CPU was also online, so we can't
just revert that fix.

The simplest fix is just to spin waiting for both active & online to be
set. We already have a barrier prior to set_cpu_online() (which also
sets active), to ensure all other setup is completed before online &
active are set.

Fixes: 6acbfb9 ("sched: Fix hotplug vs. set_cpus_allowed_ptr()")
Signed-off-by: Michael Ellerman <[email protected]>
Signed-off-by: Anton Blanchard <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
After d905c5d ("PPC: POWERNV: move iommu_add_device earlier"), the
refcnt on the kobject backing the IOMMU group for a PCI device is
elevated by each call to pci_dma_dev_setup_pSeriesLP() (via
set_iommu_table_base_and_group). When we go to dlpar a multi-function
PCI device out:

        iommu_reconfig_notifier ->
                iommu_free_table ->
                        iommu_group_put
                        BUG_ON(tbl->it_group)

We trip this BUG_ON, because there are still references on the table, so
it is not freed. Fix this by moving the powernv bus notifier to common
code and calling it for both powernv and pseries.

Fixes: d905c5d ("PPC: POWERNV: move iommu_add_device earlier")
Signed-off-by: Nishanth Aravamudan <[email protected]>
Tested-by: Nishanth Aravamudan <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
…l/git/mpe/linux

Pull powerpc fixes from Michael Ellerman:
 - Fix for dynticks.
 - Fix for smpboot bug.
 - Fix for IOMMU group refcounting.

* tag 'powerpc-4.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux:
  powerpc/iommu: Remove IOMMU device references via bus notifier
  powerpc/smp: Wait until secondaries are active & online
  powerpc: Re-enable dynticks
…nel/git/vgupta/arc

Pull ARC fixes from Vineet Gupta:
 - Fix for /proc/<pid>/maps "stack" vma annotation
 - sched stats not printing correct sleeping task PC
 - perf not reporting page faults

* tag 'arc-4.0-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARC: Fix thread_saved_pc()
  ARC: Fix KSTK_ESP()
  ARC: perf: Enable generic software events
  ARC: Make arc_unwind_core accessible externally
Pull KVM fixes from Marcelo Tosatti:
 "KVM bug fixes, including a SVM interrupt injection regression fix,
  MIPS and ARM bug fixes"

* git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: MIPS: Enable after disabling interrupt
  KVM: MIPS: Fix trace event to save PC directly
  KVM: SVM: fix interrupt injection (apic->isr_count always 0)
  KVM: emulate: fix CMPXCHG8B on 32-bit hosts
  KVM: VMX: fix build without CONFIG_SMP
  arm/arm64: KVM: Add exit reaons to kvm_exit event tracing
  ARM: KVM: Fix size check in __coherent_cache_guest_page
…/kernel/git/sumits/dma-buf

Pull dma-buf fixes from Sumit Semwal:
 "Minor timeout & other fixes on reservation/fence"

* tag 'dma-buf-for-4.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/sumits/dma-buf:
  reservation: Remove shadowing local variable 'ret'
  dma-buf/fence: don't wait when specified timeout is zero
  reservation: wait only with non-zero timeout specified (v3)
dabrace added a commit that referenced this pull request Mar 4, 2015
@dabrace dabrace merged commit 9e013c9 into dabrace:master Mar 4, 2015
dabrace pushed a commit that referenced this pull request Mar 17, 2016
As pointed by KASAN:

	BUG: KASAN: slab-out-of-bounds in memcpy+0x1d/0x40 at addr ffff880000038d8c
	Read of size 128 by task systemd-udevd/2536
	page:ffffea0000000800 count:1 mapcount:0 mapping:          (null) index:0x0 compound_mapcount: 0
	flags: 0xffff8000004000(head)
	page dumped because: kasan: bad access detected
	CPU: 1 PID: 2536 Comm: systemd-udevd Not tainted 4.5.0-rc3+ #47
	Hardware name:                  /NUC5i7RYB, BIOS RYBDWi35.86A.0350.2015.0812.1722 08/12/2015
	  ffff880000038d8c ffff8803b0f1f1e8 ffffffff81933901 0000000000000080
	  ffff8803b0f1f280 ffff8803b0f1f270 ffffffff815602c5 ffffffff8284cf93
	  ffffffff822ddc00 0000000000000282 0000000000000001 ffff88009c7c6000
	Call Trace:
	  [<ffffffff81933901>] dump_stack+0x85/0xc4
	  [<ffffffff815602c5>] kasan_report_error+0x525/0x550
	  [<ffffffff815606e9>] kasan_report+0x39/0x40
	  [<ffffffff8155f84d>] memcpy+0x1d/0x40
	  [<ffffffffa120cb90>] smscore_set_device_mode+0xee0/0x2560 [smsmdtv]

Such error happens at the memcpy code below:

0x4bc0 is in smscore_set_device_mode (drivers/media/common/siano/smscoreapi.c:975).
970					      sizeof(u32) + payload_size));
971
972			data_msg->mem_addr = mem_address;
973			memcpy(data_msg->payload, payload, payload_size);
974
975			rc = smscore_sendrequest_and_wait(coredev, data_msg,
976					data_msg->x_msg_header.msg_length,
977					&coredev->data_download_done);
978
979			payload += payload_size;

The problem is that the Siano driver uses a header to store the firmware,
with requires a few more bytes than allocated.

Tested with:
	PCTV 77e (2013:0257)
	Hauppauge WinTV MiniStick (2040:5510)

Signed-off-by: Mauro Carvalho Chehab <[email protected]>
dabrace pushed a commit that referenced this pull request Mar 17, 2016
smscore_getbuffer() calls internally wait_event(), with can sleep.
As smsusb_onresponse() is called on interrupt context, this causes
the following warning:

	BUG: sleeping function called from invalid context at drivers/media/common/siano/smscoreapi.c:1653
	in_atomic(): 1, irqs_disabled(): 1, pid: 11084, name: systemd-udevd
	INFO: lockdep is turned off.
	irq event stamp: 0
	hardirqs last  enabled at (0): [<          (null)>]           (null)
	hardirqs last disabled at (0): [<ffffffff811480f7>] copy_process.part.7+0x10e7/0x56d0
	softirqs last  enabled at (0): [<ffffffff81148193>] copy_process.part.7+0x1183/0x56d0
	softirqs last disabled at (0): [<          (null)>]           (null)
	CPU: 2 PID: 11084 Comm: systemd-udevd Tainted: G    B   W       4.5.0-rc3+ #47
	Hardware name:                  /NUC5i7RYB, BIOS RYBDWi35.86A.0350.2015.0812.1722 08/12/2015
	 0000000000000000 ffff8803c6907a80 ffffffff81933901 ffff8802bd916000
	 ffff8802bd9165c8 ffff8803c6907aa8 ffffffff811c6af5 ffff8802bd916000
	 ffffffffa0ce9b60 0000000000000675 ffff8803c6907ae8 ffffffff811c6ce5
	Call Trace:
	 <IRQ>  [<ffffffff81933901>] dump_stack+0x85/0xc4
	 [<ffffffff811c6af5>] ___might_sleep+0x245/0x3a0
	 [<ffffffff811c6ce5>] __might_sleep+0x95/0x1a0
	 [<ffffffffa0ce020a>] ? list_add_locked+0xca/0x140 [smsmdtv]
	 [<ffffffffa0ce3b8d>] smscore_getbuffer+0x7d/0x120 [smsmdtv]
	 [<ffffffff8123819d>] ? trace_hardirqs_off+0xd/0x10
	 [<ffffffffa0ce3b10>] ? smscore_sendrequest_and_wait.isra.5+0x120/0x120 [smsmdtv]
	 [<ffffffffa0ce020a>] ? list_add_locked+0xca/0x140 [smsmdtv]
	 [<ffffffffa0ce13ca>] ? smscore_putbuffer+0x3a/0x40 [smsmdtv]
	 [<ffffffffa0d107bc>] smsusb_submit_urb+0x2ec/0x4f0 [smsusb]
	 [<ffffffffa0d10e36>] smsusb_onresponse+0x476/0x720 [smsusb]

Let's add a work queue to handle the bottom half, preventing this
problem.

Signed-off-by: Mauro Carvalho Chehab <[email protected]>
dabrace pushed a commit that referenced this pull request Jul 7, 2016
UBSAN reports the following warning from accessing path->path[-1]
in set_path_power():

[   16.078040] ================================================================================
[   16.078124] UBSAN: Undefined behaviour in sound/pci/hda/hda_generic.c:3981:17
[   16.078198] index -1 is out of range for type 'hda_nid_t [10]'
[   16.078270] CPU: 2 PID: 1738 Comm: modprobe Not tainted 4.7.0-rc1-wt+ #47
[   16.078274] Hardware name: LENOVO 3443CTO/3443CTO, BIOS G6ET23WW (1.02 ) 08/14/2012
[   16.078278]  ffff8800cb246000 ffff8800cb3638b8 ffffffff815c4fe3 0000000000000032
[   16.078286]  ffff8800cb3638e0 ffffffffffffffff ffff8800cb3638d0 ffffffff8162443d
[   16.078294]  ffffffffa0894200 ffff8800cb363920 ffffffff81624af7 0000000000000292
[   16.078302] Call Trace:
[   16.078311]  [<ffffffff815c4fe3>] dump_stack+0x86/0xd3
[   16.078317]  [<ffffffff8162443d>] ubsan_epilogue+0xd/0x40
[   16.078324]  [<ffffffff81624af7>] __ubsan_handle_out_of_bounds+0x67/0x70
[   16.078335]  [<ffffffffa087665f>] set_path_power+0x1bf/0x230 [snd_hda_codec_generic]
[   16.078344]  [<ffffffffa087880d>] add_pin_power_ctls+0x8d/0xc0 [snd_hda_codec_generic]
[   16.078352]  [<ffffffffa087f190>] ? pin_power_down_callback+0x20/0x20 [snd_hda_codec_generic]
[   16.078360]  [<ffffffffa0878947>] add_all_pin_power_ctls+0x107/0x150 [snd_hda_codec_generic]
[   16.078370]  [<ffffffffa08842b3>] snd_hda_gen_parse_auto_config+0x2d73/0x49e0 [snd_hda_codec_generic]
[   16.078376]  [<ffffffff81173360>] ? trace_hardirqs_on_caller+0x1b0/0x2c0
[   16.078390]  [<ffffffffa089df27>] alc_parse_auto_config+0x147/0x310 [snd_hda_codec_realtek]
[   16.078402]  [<ffffffffa08a332a>] patch_alc269+0x23a/0x560 [snd_hda_codec_realtek]
[   16.078417]  [<ffffffffa0838644>] hda_codec_driver_probe+0xa4/0x1a0 [snd_hda_codec]
[   16.078424]  [<ffffffff817bbac1>] driver_probe_device+0x101/0x380
[   16.078430]  [<ffffffff817bbdf9>] __driver_attach+0xb9/0x100
[   16.078438]  [<ffffffff817bbd40>] ? driver_probe_device+0x380/0x380
[   16.078444]  [<ffffffff817b8d20>] bus_for_each_dev+0x70/0xc0
[   16.078449]  [<ffffffff817bb087>] driver_attach+0x27/0x50
[   16.078454]  [<ffffffff817ba956>] bus_add_driver+0x166/0x2c0
[   16.078460]  [<ffffffffa0369000>] ? 0xffffffffa0369000
[   16.078465]  [<ffffffff817bd13d>] driver_register+0x7d/0x130
[   16.078477]  [<ffffffffa083816f>] __hda_codec_driver_register+0x6f/0x90 [snd_hda_codec]
[   16.078488]  [<ffffffffa036901e>] realtek_driver_init+0x1e/0x1000 [snd_hda_codec_realtek]
[   16.078493]  [<ffffffff8100215e>] do_one_initcall+0x4e/0x1d0
[   16.078499]  [<ffffffff8119f54d>] ? rcu_read_lock_sched_held+0x6d/0x80
[   16.078504]  [<ffffffff813701b1>] ? kmem_cache_alloc_trace+0x391/0x560
[   16.078510]  [<ffffffff812bb314>] ? do_init_module+0x28/0x273
[   16.078515]  [<ffffffff812bb387>] do_init_module+0x9b/0x273
[   16.078522]  [<ffffffff811e3782>] load_module+0x20b2/0x3410
[   16.078527]  [<ffffffff811df140>] ? m_show+0x210/0x210
[   16.078533]  [<ffffffff813b2b26>] ? kernel_read+0x66/0xe0
[   16.078541]  [<ffffffff811e4cfa>] SYSC_finit_module+0xba/0xc0
[   16.078547]  [<ffffffff811e4d1e>] SyS_finit_module+0xe/0x10
[   16.078552]  [<ffffffff81a860fc>] entry_SYSCALL_64_fastpath+0x1f/0xbd
[   16.078556] ================================================================================

Fix by checking path->depth before use.

Signed-off-by: Bob Copeland <[email protected]>
Cc: <[email protected]>
Signed-off-by: Takashi Iwai <[email protected]>
dabrace pushed a commit that referenced this pull request Aug 2, 2016
Enabling interrupts may result in an interrupt raised and serviced while
VMD holds a lock, resulting in contention with the spin lock held while
enabling interrupts.

The solution is to disable preemption and save/restore the state during
interrupt enable and disable.

Fixes lockdep:

  ======================================================
  [ INFO: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected ]
  4.6.0-2016-06-16-lockdep+ #47 Tainted: G            E
  ------------------------------------------------------
  kworker/0:1/447 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
   (list_lock){+.+...}, at: [<ffffffffa04eb8fc>] vmd_irq_enable+0x3c/0x70 [vmd]

  and this task is already holding:
   (&irq_desc_lock_class){-.-...}, at: [<ffffffff810e1ff6>] __setup_irq+0xa6/0x610
  which would create a new lock dependency:
   (&irq_desc_lock_class){-.-...} -> (list_lock){+.+...}

  but this new dependency connects a HARDIRQ-irq-safe lock:
   (&irq_desc_lock_class){-.-...}
  ... which became HARDIRQ-irq-safe at:
    [<ffffffff810c9f21>] __lock_acquire+0x981/0xe00
    [<ffffffff810cb039>] lock_acquire+0x119/0x220
    [<ffffffff8167294d>] _raw_spin_lock+0x3d/0x80
    [<ffffffff810e36d4>] handle_level_irq+0x24/0x110
    [<ffffffff8101f20a>] handle_irq+0x1a/0x30
    [<ffffffff81675fc1>] do_IRQ+0x61/0x120
    [<ffffffff8167404c>] ret_from_intr+0x0/0x20
    [<ffffffff81672e30>] _raw_spin_unlock_irqrestore+0x40/0x60
    [<ffffffff810e21ee>] __setup_irq+0x29e/0x610
    [<ffffffff810e25a1>] setup_irq+0x41/0x90
    [<ffffffff81f5777f>] setup_default_timer_irq+0x1e/0x20
    [<ffffffff81f57798>] hpet_time_init+0x17/0x19
    [<ffffffff81f5775a>] x86_late_time_init+0xa/0x11
    [<ffffffff81f51e9b>] start_kernel+0x382/0x436
    [<ffffffff81f51308>] x86_64_start_reservations+0x2a/0x2c
    [<ffffffff81f51445>] x86_64_start_kernel+0x13b/0x14a

  to a HARDIRQ-irq-unsafe lock:
   (list_lock){+.+...}
  ... which became HARDIRQ-irq-unsafe at:
  ...  [<ffffffff810c9d8e>] __lock_acquire+0x7ee/0xe00
    [<ffffffff810cb039>] lock_acquire+0x119/0x220
    [<ffffffff8167294d>] _raw_spin_lock+0x3d/0x80
    [<ffffffffa04eba42>] vmd_msi_init+0x72/0x150 [vmd]
    [<ffffffff810e8597>] msi_domain_alloc+0xb7/0x140
    [<ffffffff810e6b10>] irq_domain_alloc_irqs_recursive+0x40/0xa0
    [<ffffffff810e6cea>] __irq_domain_alloc_irqs+0x14a/0x330
    [<ffffffff810e8a8c>] msi_domain_alloc_irqs+0x8c/0x1d0
    [<ffffffff813ca4e3>] pci_msi_setup_msi_irqs+0x43/0x70
    [<ffffffff813cada1>] pci_enable_msi_range+0x131/0x280
    [<ffffffff813bf5e0>] pcie_port_device_register+0x320/0x4e0
    [<ffffffff813bf9a4>] pcie_portdrv_probe+0x34/0x60
    [<ffffffff813b0e85>] local_pci_probe+0x45/0xa0
    [<ffffffff813b226b>] pci_device_probe+0xdb/0x130
    [<ffffffff8149e3cc>] driver_probe_device+0x22c/0x440
    [<ffffffff8149e774>] __device_attach_driver+0x94/0x110
    [<ffffffff8149bfad>] bus_for_each_drv+0x5d/0x90
    [<ffffffff8149e030>] __device_attach+0xc0/0x140
    [<ffffffff8149e0c0>] device_attach+0x10/0x20
    [<ffffffff813a77f7>] pci_bus_add_device+0x47/0x90
    [<ffffffff813a7879>] pci_bus_add_devices+0x39/0x70
    [<ffffffff813aaba7>] pci_rescan_bus+0x27/0x30
    [<ffffffffa04ec1af>] vmd_probe+0x68f/0x76c [vmd]
    [<ffffffff813b0e85>] local_pci_probe+0x45/0xa0
    [<ffffffff81088064>] work_for_cpu_fn+0x14/0x20
    [<ffffffff8108c244>] process_one_work+0x1f4/0x740
    [<ffffffff8108c9c6>] worker_thread+0x236/0x4f0
    [<ffffffff810935c2>] kthread+0xf2/0x110
    [<ffffffff816738f2>] ret_from_fork+0x22/0x50

  other info that might help us debug this:

   Possible interrupt unsafe locking scenario:

	 CPU0                    CPU1
	 ----                    ----
    lock(list_lock);
				 local_irq_disable();
				 lock(&irq_desc_lock_class);
				 lock(list_lock);
    <Interrupt>
      lock(&irq_desc_lock_class);

   *** DEADLOCK ***

Signed-off-by: Jon Derrick <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Acked-by: Keith Busch <[email protected]>
dabrace pushed a commit that referenced this pull request Nov 28, 2016
Reported by syzkaller:

    [ INFO: suspicious RCU usage. ]
    4.9.0-rc4+ #47 Not tainted
    -------------------------------
    ./include/linux/kvm_host.h:536 suspicious rcu_dereference_check() usage!

    stack backtrace:
    CPU: 1 PID: 6679 Comm: syz-executor Not tainted 4.9.0-rc4+ #47
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
     ffff880039e2f6d0 ffffffff81c2e46b ffff88003e3a5b40 0000000000000000
     0000000000000001 ffffffff83215600 ffff880039e2f700 ffffffff81334ea9
     ffffc9000730b000 0000000000000004 ffff88003c4f8420 ffff88003d3f8000
    Call Trace:
     [<     inline     >] __dump_stack lib/dump_stack.c:15
     [<ffffffff81c2e46b>] dump_stack+0xb3/0x118 lib/dump_stack.c:51
     [<ffffffff81334ea9>] lockdep_rcu_suspicious+0x139/0x180 kernel/locking/lockdep.c:4445
     [<     inline     >] __kvm_memslots include/linux/kvm_host.h:534
     [<     inline     >] kvm_memslots include/linux/kvm_host.h:541
     [<ffffffff8105d6ae>] kvm_gfn_to_hva_cache_init+0xa1e/0xce0 virt/kvm/kvm_main.c:1941
     [<ffffffff8112685d>] kvm_lapic_set_vapic_addr+0xed/0x140 arch/x86/kvm/lapic.c:2217

Reported-by: Dmitry Vyukov <[email protected]>
Fixes: fda4e2e
Cc: Andrew Honig <[email protected]>
Cc: [email protected]
Signed-off-by: Paolo Bonzini <[email protected]>
Reviewed-by: David Hildenbrand <[email protected]>
Signed-off-by: Radim Krčmář <[email protected]>
dabrace pushed a commit that referenced this pull request Apr 25, 2017
calculate_min_delta() may incorrectly access a 4th element of buf2[]
which only has 3 elements. This may trigger undefined behaviour and has
been reported to cause strange crashes in start_kernel() sometime after
timer initialization when built with GCC 5.3, possibly due to
register/stack corruption:

sched_clock: 32 bits at 200MHz, resolution 5ns, wraps every 10737418237ns
CPU 0 Unable to handle kernel paging request at virtual address ffffb0aa, epc == 8067daa8, ra == 8067da84
Oops[#1]:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.9.18 #51
task: 8065e3e0 task.stack: 80644000
$ 0   : 00000000 00000001 00000000 00000000
$ 4   : 8065b4d0 00000000 805d0000 00000010
$ 8   : 00000010 80321400 fffff000 812de408
$12   : 00000000 00000000 00000000 ffffffff
$16   : 00000002 ffffffff 80660000 806a666c
$20   : 806c0000 00000000 00000000 00000000
$24   : 00000000 00000010
$28   : 80644000 80645ed0 00000000 8067da84
Hi    : 00000000
Lo    : 00000000
epc   : 8067daa8 start_kernel+0x33c/0x500
ra    : 8067da84 start_kernel+0x318/0x500
Status: 11000402 KERNEL EXL
Cause : 4080040c (ExcCode 03)
BadVA : ffffb0aa
PrId  : 0501992c (MIPS 1004Kc)
Modules linked in:
Process swapper/0 (pid: 0, threadinfo=80644000, task=8065e3e0, tls=00000000)
Call Trace:
[<8067daa8>] start_kernel+0x33c/0x500
Code: 24050240  0c0131f9  24849c64 <a200b0a8> 41606020  000000c0  0c1a45e6 00000000  0c1a5f44

UBSAN also detects the same issue:

================================================================
UBSAN: Undefined behaviour in arch/mips/kernel/cevt-r4k.c:85:41
load of address 80647e4c with insufficient space
for an object of type 'unsigned int'
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.9.18 #47
Call Trace:
[<80028f70>] show_stack+0x88/0xa4
[<80312654>] dump_stack+0x84/0xc0
[<8034163c>] ubsan_epilogue+0x14/0x50
[<803417d8>] __ubsan_handle_type_mismatch+0x160/0x168
[<8002dab0>] r4k_clockevent_init+0x544/0x764
[<80684d34>] time_init+0x18/0x90
[<8067fa5c>] start_kernel+0x2f0/0x500
=================================================================

buf2[] is intentionally only 3 elements so that the last element is the
median once 5 samples have been inserted, so explicitly prevent the
possibility of comparing against the 4th element rather than extending
the array.

Fixes: 1fa4055 ("MIPS: cevt-r4k: Dynamically calculate min_delta_ns")
Reported-by: Rabin Vincent <[email protected]>
Signed-off-by: James Hogan <[email protected]>
Tested-by: Rabin Vincent <[email protected]>
Cc: [email protected]
Cc: <[email protected]> # 4.7.x-
Patchwork: https://patchwork.linux-mips.org/patch/15892/
Signed-off-by: Ralf Baechle <[email protected]>
dabrace pushed a commit that referenced this pull request Jun 16, 2017
…e spin_lock

This patch uses spin_lock_init() instead of __SPIN_LOCK_UNLOCKED() to
initialize the per namespace net->can.can_rcvlists_lock lock to fix this
lockdep warning:

| INFO: trying to register non-static key.
| the code is fine but needs lockdep annotation.
| turning off the locking correctness validator.
| CPU: 0 PID: 186 Comm: candump Not tainted 4.12.0-rc3+ #47
| Hardware name: Marvell Kirkwood (Flattened Device Tree)
| [<c0016644>] (unwind_backtrace) from [<c00139a8>] (show_stack+0x18/0x1c)
| [<c00139a8>] (show_stack) from [<c0058c8c>] (register_lock_class+0x1e4/0x55c)
| [<c0058c8c>] (register_lock_class) from [<c005bdfc>] (__lock_acquire+0x148/0x1990)
| [<c005bdfc>] (__lock_acquire) from [<c005deec>] (lock_acquire+0x174/0x210)
| [<c005deec>] (lock_acquire) from [<c04a6780>] (_raw_spin_lock+0x50/0x88)
| [<c04a6780>] (_raw_spin_lock) from [<bf02116c>] (can_rx_register+0x94/0x15c [can])
| [<bf02116c>] (can_rx_register [can]) from [<bf02a868>] (raw_enable_filters+0x60/0xc0 [can_raw])
| [<bf02a868>] (raw_enable_filters [can_raw]) from [<bf02ac14>] (raw_enable_allfilters+0x2c/0xa0 [can_raw])
| [<bf02ac14>] (raw_enable_allfilters [can_raw]) from [<bf02ad38>] (raw_bind+0xb0/0x250 [can_raw])
| [<bf02ad38>] (raw_bind [can_raw]) from [<c03b5fb8>] (SyS_bind+0x70/0xac)
| [<c03b5fb8>] (SyS_bind) from [<c000f8c0>] (ret_fast_syscall+0x0/0x1c)

Cc: Mario Kicherer <[email protected]>
Acked-by: Oliver Hartkopp <[email protected]>
Signed-off-by: Marc Kleine-Budde <[email protected]>
dabrace pushed a commit that referenced this pull request Jan 9, 2018
This function is used from two places: rtnl_dump_ifinfo and
rtnl_getlink. In rtnl_getlink(), we give a request skb into
get_target_net(), but in rtnl_dump_ifinfo, we give a response skb
into get_target_net().
The problem here is that NETLINK_CB() isn't initialized for the response
skb. In both cases we can get a user socket and give it instead of skb
into get_target_net().

This bug was found by syzkaller with this call-trace:

kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Modules linked in:
CPU: 1 PID: 3149 Comm: syzkaller140561 Not tainted 4.15.0-rc4-mm1+ #47
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:__netlink_ns_capable+0x8b/0x120 net/netlink/af_netlink.c:868
RSP: 0018:ffff8801c880f348 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff8443f900
RDX: 000000000000007b RSI: ffffffff86510f40 RDI: 00000000000003d8
RBP: ffff8801c880f360 R08: 0000000000000000 R09: 1ffff10039101e4f
R10: 0000000000000000 R11: 0000000000000001 R12: ffffffff86510f40
R13: 000000000000000c R14: 0000000000000004 R15: 0000000000000011
FS:  0000000001a1a880(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020151000 CR3: 00000001c9511005 CR4: 00000000001606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
  netlink_ns_capable+0x26/0x30 net/netlink/af_netlink.c:886
  get_target_net+0x9d/0x120 net/core/rtnetlink.c:1765
  rtnl_dump_ifinfo+0x2e5/0xee0 net/core/rtnetlink.c:1806
  netlink_dump+0x48c/0xce0 net/netlink/af_netlink.c:2222
  __netlink_dump_start+0x4f0/0x6d0 net/netlink/af_netlink.c:2319
  netlink_dump_start include/linux/netlink.h:214 [inline]
  rtnetlink_rcv_msg+0x7f0/0xb10 net/core/rtnetlink.c:4485
  netlink_rcv_skb+0x21e/0x460 net/netlink/af_netlink.c:2441
  rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:4540
  netlink_unicast_kernel net/netlink/af_netlink.c:1308 [inline]
  netlink_unicast+0x4be/0x6a0 net/netlink/af_netlink.c:1334
  netlink_sendmsg+0xa4a/0xe60 net/netlink/af_netlink.c:1897

Cc: Jiri Benc <[email protected]>
Fixes: 79e1ad1 ("rtnetlink: use netnsid to query interface")
Signed-off-by: Andrei Vagin <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
dabrace pushed a commit that referenced this pull request May 21, 2018
syzbot caught an infinite recursion in nsh_gso_segment().

Problem here is that we need to make sure the NSH header is of
reasonable length.

BUG: MAX_LOCK_DEPTH too low!
turning off the locking correctness validator.
depth: 48  max: 48!
48 locks held by syz-executor0/10189:
 #0:         (ptrval) (rcu_read_lock_bh){....}, at: __dev_queue_xmit+0x30f/0x34c0 net/core/dev.c:3517
 #1:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #1:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #2:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #2:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #3:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #3:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #4:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #4:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #5:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #5:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #6:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #6:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #7:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #7:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #8:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #8:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #9:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #9:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #10:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #10:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #11:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #11:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #12:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #12:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #13:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #13:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #14:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #14:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #15:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #15:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #16:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #16:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #17:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #17:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #18:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #18:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #19:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #19:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #20:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #20:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #21:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #21:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #22:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #22:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #23:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #23:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #24:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #24:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #25:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #25:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #26:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #26:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #27:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #27:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #28:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #28:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #29:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #29:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #30:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #30:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #31:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #31:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
dccp_close: ABORT with 65423 bytes unread
 #32:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #32:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #33:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #33:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #34:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #34:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #35:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #35:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #36:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #36:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #37:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #37:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #38:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #38:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #39:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #39:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #40:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #40:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #41:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #41:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #42:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #42:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #43:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #43:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #44:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #44:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #45:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #45:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #46:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #46:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
 #47:         (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline]
 #47:         (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787
INFO: lockdep is turned off.
CPU: 1 PID: 10189 Comm: syz-executor0 Not tainted 4.17.0-rc2+ #26
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1b9/0x294 lib/dump_stack.c:113
 __lock_acquire+0x1788/0x5140 kernel/locking/lockdep.c:3449
 lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3920
 rcu_lock_acquire include/linux/rcupdate.h:246 [inline]
 rcu_read_lock include/linux/rcupdate.h:632 [inline]
 skb_mac_gso_segment+0x25b/0x720 net/core/dev.c:2789
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107
 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792
 __skb_gso_segment+0x3bb/0x870 net/core/dev.c:2865
 skb_gso_segment include/linux/netdevice.h:4025 [inline]
 validate_xmit_skb+0x54d/0xd90 net/core/dev.c:3118
 validate_xmit_skb_list+0xbf/0x120 net/core/dev.c:3168
 sch_direct_xmit+0x354/0x11e0 net/sched/sch_generic.c:312
 qdisc_restart net/sched/sch_generic.c:399 [inline]
 __qdisc_run+0x741/0x1af0 net/sched/sch_generic.c:410
 __dev_xmit_skb net/core/dev.c:3243 [inline]
 __dev_queue_xmit+0x28ea/0x34c0 net/core/dev.c:3551
 dev_queue_xmit+0x17/0x20 net/core/dev.c:3616
 packet_snd net/packet/af_packet.c:2951 [inline]
 packet_sendmsg+0x40f8/0x6070 net/packet/af_packet.c:2976
 sock_sendmsg_nosec net/socket.c:629 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:639
 __sys_sendto+0x3d7/0x670 net/socket.c:1789
 __do_sys_sendto net/socket.c:1801 [inline]
 __se_sys_sendto net/socket.c:1797 [inline]
 __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1797
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: c411ed8 ("nsh: add GSO support")
Signed-off-by: Eric Dumazet <[email protected]>
Cc: Jiri Benc <[email protected]>
Reported-by: syzbot <[email protected]>
Acked-by: Jiri Benc <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
dabrace pushed a commit that referenced this pull request Nov 12, 2018
Increase kasan instrumented kernel stack size from 32k to 64k. Other
architectures seems to get away with just doubling kernel stack size under
kasan, but on s390 this appears to be not enough due to bigger frame size.
The particular pain point is kasan inlined checks (CONFIG_KASAN_INLINE
vs CONFIG_KASAN_OUTLINE). With inlined checks one particular case hitting
stack overflow is fs sync on xfs filesystem:

 #0 [9a0681e8]  704 bytes  check_usage at 34b1fc
 #1 [9a0684a8]  432 bytes  check_usage at 34c710
 #2 [9a068658]  1048 bytes  validate_chain at 35044a
 #3 [9a068a70]  312 bytes  __lock_acquire at 3559fe
 #4 [9a068ba8]  440 bytes  lock_acquire at 3576ee
 #5 [9a068d60]  104 bytes  _raw_spin_lock at 21b44e0
 #6 [9a068dc8]  1992 bytes  enqueue_entity at 2dbf72
 #7 [9a069590]  1496 bytes  enqueue_task_fair at 2df5f0
 #8 [9a069b68]  64 bytes  ttwu_do_activate at 28f438
 #9 [9a069ba8]  552 bytes  try_to_wake_up at 298c4c
 #10 [9a069dd0]  168 bytes  wake_up_worker at 23f97c
 #11 [9a069e78]  200 bytes  insert_work at 23fc2e
 #12 [9a069f40]  648 bytes  __queue_work at 2487c0
 #13 [9a06a1c8]  200 bytes  __queue_delayed_work at 24db28
 #14 [9a06a290]  248 bytes  mod_delayed_work_on at 24de84
 #15 [9a06a388]  24 bytes  kblockd_mod_delayed_work_on at 153e2a0
 #16 [9a06a3a0]  288 bytes  __blk_mq_delay_run_hw_queue at 158168c
 #17 [9a06a4c0]  192 bytes  blk_mq_run_hw_queue at 1581a3c
 #18 [9a06a580]  184 bytes  blk_mq_sched_insert_requests at 15a2192
 #19 [9a06a638]  1024 bytes  blk_mq_flush_plug_list at 1590f3a
 #20 [9a06aa38]  704 bytes  blk_flush_plug_list at 1555028
 #21 [9a06acf8]  320 bytes  schedule at 219e476
 #22 [9a06ae38]  760 bytes  schedule_timeout at 21b0aac
 #23 [9a06b130]  408 bytes  wait_for_common at 21a1706
 #24 [9a06b2c8]  360 bytes  xfs_buf_iowait at fa1540
 #25 [9a06b430]  256 bytes  __xfs_buf_submit at fadae6
 #26 [9a06b530]  264 bytes  xfs_buf_read_map at fae3f6
 #27 [9a06b638]  656 bytes  xfs_trans_read_buf_map at 10ac9a8
 #28 [9a06b8c8]  304 bytes  xfs_btree_kill_root at e72426
 #29 [9a06b9f8]  288 bytes  xfs_btree_lookup_get_block at e7bc5e
 #30 [9a06bb18]  624 bytes  xfs_btree_lookup at e7e1a6
 #31 [9a06bd88]  2664 bytes  xfs_alloc_ag_vextent_near at dfa070
 #32 [9a06c7f0]  144 bytes  xfs_alloc_ag_vextent at dff3ca
 #33 [9a06c880]  1128 bytes  xfs_alloc_vextent at e05fce
 #34 [9a06cce8]  584 bytes  xfs_bmap_btalloc at e58342
 #35 [9a06cf30]  1336 bytes  xfs_bmapi_write at e618de
 #36 [9a06d468]  776 bytes  xfs_iomap_write_allocate at ff678e
 #37 [9a06d770]  720 bytes  xfs_map_blocks at f82af8
 #38 [9a06da40]  928 bytes  xfs_writepage_map at f83cd6
 #39 [9a06dde0]  320 bytes  xfs_do_writepage at f85872
 #40 [9a06df20]  1320 bytes  write_cache_pages at 73dfe8
 #41 [9a06e448]  208 bytes  xfs_vm_writepages at f7f892
 #42 [9a06e518]  88 bytes  do_writepages at 73fe6a
 #43 [9a06e570]  872 bytes  __writeback_single_inode at a20cb6
 #44 [9a06e8d8]  664 bytes  writeback_sb_inodes at a23be2
 #45 [9a06eb70]  296 bytes  __writeback_inodes_wb at a242e0
 #46 [9a06ec98]  928 bytes  wb_writeback at a2500e
 #47 [9a06f038]  848 bytes  wb_do_writeback at a260ae
 #48 [9a06f388]  536 bytes  wb_workfn at a28228
 #49 [9a06f5a0]  1088 bytes  process_one_work at 24a234
 #50 [9a06f9e0]  1120 bytes  worker_thread at 24ba26
 #51 [9a06fe40]  104 bytes  kthread at 26545a
 #52 [9a06fea8]             kernel_thread_starter at 21b6b62

To be able to increase the stack size to 64k reuse LLILL instruction
in __switch_to function to load 64k - STACK_FRAME_OVERHEAD - __PT_SIZE
(65192) value as unsigned.

Reported-by: Benjamin Block <[email protected]>
Reviewed-by: Heiko Carstens <[email protected]>
Signed-off-by: Vasily Gorbik <[email protected]>
Signed-off-by: Martin Schwidefsky <[email protected]>
dabrace pushed a commit that referenced this pull request May 10, 2019
kernel BUG at lib/list_debug.c:47!
invalid opcode: 0000 [#1
CPU: 0 PID: 12914 Comm: rmmod Tainted: G        W         5.1.0+ #47
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014
RIP: 0010:__list_del_entry_valid+0x53/0x90
Code: 48 8b 32 48 39 fe 75 35 48 8b 50 08 48 39 f2 75 40 b8 01 00 00 00 5d c3 48
89 fe 48 89 c2 48 c7 c7 18 75 fe 82 e8 cb 34 78 ff <0f> 0b 48 89 fe 48 c7 c7 50 75 fe 82 e8 ba 34 78 ff 0f 0b 48 89 f2
RSP: 0018:ffffc90001c2fe40 EFLAGS: 00010286
RAX: 000000000000004e RBX: ffffffffa0184000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff888237a17788 RDI: 00000000ffffffff
RBP: ffffc90001c2fe40 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc90001c2fe10 R11: 0000000000000000 R12: 0000000000000000
R13: ffffc90001c2fe50 R14: ffffffffa0184000 R15: 0000000000000000
FS:  00007f3d83634540(0000) GS:ffff888237a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555c350ea818 CR3: 0000000231677000 CR4: 00000000000006f0
Call Trace:
 unregister_pernet_operations+0x34/0x120
 unregister_pernet_subsys+0x1c/0x30
 packet_exit+0x1c/0x369 [af_packet
 __x64_sys_delete_module+0x156/0x260
 ? lockdep_hardirqs_on+0x133/0x1b0
 ? do_syscall_64+0x12/0x1f0
 do_syscall_64+0x6e/0x1f0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

When modprobe af_packet, register_pernet_subsys
fails and does a cleanup, ops->list is set to LIST_POISON1,
but the module init is considered to success, then while rmmod it,
BUG() is triggered in __list_del_entry_valid which is called from
unregister_pernet_subsys. This patch fix error handing path in
packet_init to avoid possilbe issue if some error occur.

Reported-by: Hulk Robot <[email protected]>
Signed-off-by: YueHaibing <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
dabrace pushed a commit that referenced this pull request Jun 3, 2019
…slots

According to Documentation/virtual/kvm/locking.txt, the srcu read lock
should be taken when accessing the memslots of the VM. The XIVE KVM
device needs to do so when configuring the page of the OS event queue
of vCPU for a given priority and when marking the same page dirty
before migration.

This avoids warnings such as :

[  208.224882] =============================
[  208.224884] WARNING: suspicious RCU usage
[  208.224889] 5.2.0-rc2-xive+ #47 Not tainted
[  208.224890] -----------------------------
[  208.224894] ../include/linux/kvm_host.h:633 suspicious rcu_dereference_check() usage!
[  208.224896]
               other info that might help us debug this:

[  208.224898]
               rcu_scheduler_active = 2, debug_locks = 1
[  208.224901] no locks held by qemu-system-ppc/3923.
[  208.224902]
               stack backtrace:
[  208.224907] CPU: 64 PID: 3923 Comm: qemu-system-ppc Kdump: loaded Not tainted 5.2.0-rc2-xive+ #47
[  208.224909] Call Trace:
[  208.224918] [c000200cdd98fa30] [c000000000be1934] dump_stack+0xe8/0x164 (unreliable)
[  208.224924] [c000200cdd98fa80] [c0000000001aec80] lockdep_rcu_suspicious+0x110/0x180
[  208.224935] [c000200cdd98fb00] [c0080000075933a0] gfn_to_memslot+0x1c8/0x200 [kvm]
[  208.224943] [c000200cdd98fb40] [c008000007599600] gfn_to_pfn+0x28/0x60 [kvm]
[  208.224951] [c000200cdd98fb70] [c008000007599658] gfn_to_page+0x20/0x40 [kvm]
[  208.224959] [c000200cdd98fb90] [c0080000075b495c] kvmppc_xive_native_set_attr+0x8b4/0x1480 [kvm]
[  208.224967] [c000200cdd98fca0] [c00800000759261c] kvm_device_ioctl_attr+0x64/0xb0 [kvm]
[  208.224974] [c000200cdd98fcf0] [c008000007592730] kvm_device_ioctl+0xc8/0x110 [kvm]
[  208.224979] [c000200cdd98fd10] [c000000000433a24] do_vfs_ioctl+0xd4/0xcd0
[  208.224981] [c000200cdd98fdb0] [c000000000434724] ksys_ioctl+0x104/0x120
[  208.224984] [c000200cdd98fe00] [c000000000434768] sys_ioctl+0x28/0x80
[  208.224988] [c000200cdd98fe20] [c00000000000b888] system_call+0x5c/0x70
legoater@boss01:~$

Fixes: 13ce329 ("KVM: PPC: Book3S HV: XIVE: Add controls for the EQ configuration")
Fixes: e6714bd ("KVM: PPC: Book3S HV: XIVE: Add a control to dirty the XIVE EQ pages")
Signed-off-by: Cédric Le Goater <[email protected]>
Signed-off-by: Paul Mackerras <[email protected]>
dabrace pushed a commit that referenced this pull request Jan 8, 2020
When enabling ftrace graph tracer, it gets the tracing clock in
ftrace_push_return_trace().  Eventually, it invokes riscv_sched_clock()
to get the clock value.  If riscv_sched_clock() isn't marked with
'notrace', it will call ftrace_push_return_trace() and cause infinite
loop.

The result of failure as follow:

command: echo function_graph >current_tracer
[   46.176787] Unable to handle kernel paging request at virtual address ffffffe04fb38c48
[   46.177309] Oops [#1]
[   46.177478] Modules linked in:
[   46.177770] CPU: 0 PID: 256 Comm: $d Not tainted 5.5.0-rc1 #47
[   46.177981] epc: ffffffe00035e59a ra : ffffffe00035e57e sp : ffffffe03a7569b0
[   46.178216]  gp : ffffffe000d29b90 tp : ffffffe03a756180 t0 : ffffffe03a756968
[   46.178430]  t1 : ffffffe00087f408 t2 : ffffffe03a7569a0 s0 : ffffffe03a7569f0
[   46.178643]  s1 : ffffffe00087f408 a0 : 0000000ac054cda4 a1 : 000000000087f411
[   46.178856]  a2 : 0000000ac054cda4 a3 : 0000000000373ca0 a4 : ffffffe04fb38c48
[   46.179099]  a5 : 00000000153e22a8 a6 : 00000000005522ff a7 : 0000000000000005
[   46.179338]  s2 : ffffffe03a756a90 s3 : ffffffe00032811c s4 : ffffffe03a756a58
[   46.179570]  s5 : ffffffe000d29fe0 s6 : 0000000000000001 s7 : 0000000000000003
[   46.179809]  s8 : 0000000000000003 s9 : 0000000000000002 s10: 0000000000000004
[   46.180053]  s11: 0000000000000000 t3 : 0000003fc815749c t4 : 00000000000efc90
[   46.180293]  t5 : ffffffe000d29658 t6 : 0000000000040000
[   46.180482] status: 0000000000000100 badaddr: ffffffe04fb38c48 cause: 000000000000000f

Signed-off-by: Zong Li <[email protected]>
Reviewed-by: Steven Rostedt (VMware) <[email protected]>
[[email protected]: cleaned up patch description]
Fixes: 92e0d14 ("clocksource/drivers/riscv_timer: Provide the sched_clock")
Cc: [email protected]
Signed-off-by: Paul Walmsley <[email protected]>
dabrace pushed a commit that referenced this pull request Sep 21, 2020
Running the eBPF test_verifier leads to random errors looking like this:

[ 6525.735488] Unexpected kernel BRK exception at EL1
[ 6525.735502] Internal error: ptrace BRK handler: f2000100 [#1] SMP
[ 6525.741609] Modules linked in: nls_utf8 cifs libdes libarc4 dns_resolver fscache binfmt_misc nls_ascii nls_cp437 vfat fat aes_ce_blk crypto_simd cryptd aes_ce_cipher ghash_ce gf128mul efi_pstore sha2_ce sha256_arm64 sha1_ce evdev efivars efivarfs ip_tables x_tables autofs4 btrfs blake2b_generic xor xor_neon zstd_compress raid6_pq libcrc32c crc32c_generic ahci xhci_pci libahci xhci_hcd igb libata i2c_algo_bit nvme realtek usbcore nvme_core scsi_mod t10_pi netsec mdio_devres of_mdio gpio_keys fixed_phy libphy gpio_mb86s7x
[ 6525.787760] CPU: 3 PID: 7881 Comm: test_verifier Tainted: G        W         5.9.0-rc1+ #47
[ 6525.796111] Hardware name: Socionext SynQuacer E-series DeveloperBox, BIOS build #1 Jun  6 2020
[ 6525.804812] pstate: 20000005 (nzCv daif -PAN -UAO BTYPE=--)
[ 6525.810390] pc : bpf_prog_c3d01833289b6311_F+0xc8/0x9f4
[ 6525.815613] lr : bpf_prog_d53bb52e3f4483f9_F+0x38/0xc8c
[ 6525.820832] sp : ffff8000130cbb80
[ 6525.824141] x29: ffff8000130cbbb0 x28: 0000000000000000
[ 6525.829451] x27: 000005ef6fcbf39b x26: 0000000000000000
[ 6525.834759] x25: ffff8000130cbb80 x24: ffff800011dc7038
[ 6525.840067] x23: ffff8000130cbd00 x22: ffff0008f624d080
[ 6525.845375] x21: 0000000000000001 x20: ffff800011dc7000
[ 6525.850682] x19: 0000000000000000 x18: 0000000000000000
[ 6525.855990] x17: 0000000000000000 x16: 0000000000000000
[ 6525.861298] x15: 0000000000000000 x14: 0000000000000000
[ 6525.866606] x13: 0000000000000000 x12: 0000000000000000
[ 6525.871913] x11: 0000000000000001 x10: ffff8000000a660c
[ 6525.877220] x9 : ffff800010951810 x8 : ffff8000130cbc38
[ 6525.882528] x7 : 0000000000000000 x6 : 0000009864cfa881
[ 6525.887836] x5 : 00ffffffffffffff x4 : 002880ba1a0b3e9f
[ 6525.893144] x3 : 0000000000000018 x2 : ffff8000000a4374
[ 6525.898452] x1 : 000000000000000a x0 : 0000000000000009
[ 6525.903760] Call trace:
[ 6525.906202]  bpf_prog_c3d01833289b6311_F+0xc8/0x9f4
[ 6525.911076]  bpf_prog_d53bb52e3f4483f9_F+0x38/0xc8c
[ 6525.915957]  bpf_dispatcher_xdp_func+0x14/0x20
[ 6525.920398]  bpf_test_run+0x70/0x1b0
[ 6525.923969]  bpf_prog_test_run_xdp+0xec/0x190
[ 6525.928326]  __do_sys_bpf+0xc88/0x1b28
[ 6525.932072]  __arm64_sys_bpf+0x24/0x30
[ 6525.935820]  el0_svc_common.constprop.0+0x70/0x168
[ 6525.940607]  do_el0_svc+0x28/0x88
[ 6525.943920]  el0_sync_handler+0x88/0x190
[ 6525.947838]  el0_sync+0x140/0x180
[ 6525.951154] Code: d4202000 d4202000 d4202000 d4202000 (d4202000)
[ 6525.957249] ---[ end trace cecc3f93b14927e2 ]---

The reason is the offset[] creation and later usage, while building
the eBPF body. The code currently omits the first instruction, since
build_insn() will increase our ctx->idx before saving it.
That was fine up until bounded eBPF loops were introduced. After that
introduction, offset[0] must be the offset of the end of prologue which
is the start of the 1st insn while, offset[n] holds the
offset of the end of n-th insn.

When "taken loop with back jump to 1st insn" test runs, it will
eventually call bpf2a64_offset(-1, 2, ctx). Since negative indexing is
permitted, the current outcome depends on the value stored in
ctx->offset[-1], which has nothing to do with our array.
If the value happens to be 0 the tests will work. If not this error
triggers.

commit 7c2e988 ("bpf: fix x64 JIT code generation for jmp to 1st insn")
fixed an indentical bug on x86 when eBPF bounded loops were introduced.

So let's fix it by creating the ctx->offset[] differently. Track the
beginning of instruction and account for the extra instruction while
calculating the arm instruction offsets.

Fixes: 2589726 ("bpf: introduce bounded loops")
Reported-by: Naresh Kamboju <[email protected]>
Reported-by: Jiri Olsa <[email protected]>
Co-developed-by: Jean-Philippe Brucker <[email protected]>
Co-developed-by: Yauheni Kaliuta <[email protected]>
Signed-off-by: Jean-Philippe Brucker <[email protected]>
Signed-off-by: Yauheni Kaliuta <[email protected]>
Signed-off-by: Ilias Apalodimas <[email protected]>
Acked-by: Will Deacon <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Catalin Marinas <[email protected]>
dabrace pushed a commit that referenced this pull request May 6, 2021
Ritesh reported a bug [1] against UML, noting that it crashed on
startup. The backtrace shows the following (heavily redacted):

(gdb) bt
...
 #26 0x0000000060015b5d in sem_init () at ipc/sem.c:268
 #27 0x00007f89906d92f7 in ?? () from /lib/x86_64-linux-gnu/libcom_err.so.2
 #28 0x00007f8990ab8fb2 in call_init (...) at dl-init.c:72
...
 #40 0x00007f89909bf3a6 in nss_load_library (...) at nsswitch.c:359
...
 #44 0x00007f8990895e35 in _nss_compat_getgrnam_r (...) at nss_compat/compat-grp.c:486
 #45 0x00007f8990968b85 in __getgrnam_r [...]
 #46 0x00007f89909d6b77 in grantpt [...]
 #47 0x00007f8990a9394e in __GI_openpty [...]
 #48 0x00000000604a1f65 in openpty_cb (...) at arch/um/os-Linux/sigio.c:407
 #49 0x00000000604a58d0 in start_idle_thread (...) at arch/um/os-Linux/skas/process.c:598
 #50 0x0000000060004a3d in start_uml () at arch/um/kernel/skas/process.c:45
 #51 0x00000000600047b2 in linux_main (...) at arch/um/kernel/um_arch.c:334
 #52 0x000000006000574f in main (...) at arch/um/os-Linux/main.c:144

indicating that the UML function openpty_cb() calls openpty(),
which internally calls __getgrnam_r(), which causes the nsswitch
machinery to get started.

This loads, through lots of indirection that I snipped, the
libcom_err.so.2 library, which (in an unknown function, "??")
calls sem_init().

Now, of course it wants to get libpthread's sem_init(), since
it's linked against libpthread. However, the dynamic linker
looks up that symbol against the binary first, and gets the
kernel's sem_init().

Hajime Tazaki noted that "objcopy -L" can localize a symbol,
so the dynamic linker wouldn't do the lookup this way. I tried,
but for some reason that didn't seem to work.

Doing the same thing in the linker script instead does seem to
work, though I cannot entirely explain - it *also* works if I
just add "VERSION { { global: *; }; }" instead, indicating that
something else is happening that I don't really understand. It
may be that explicitly doing that marks them with some kind of
empty version, and that's different from the default.

Explicitly marking them with a version breaks kallsyms, so that
doesn't seem to be possible.

Marking all the symbols as local seems correct, and does seem
to address the issue, so do that. Also do it for static link,
nsswitch libraries could still be loaded there.

[1] https://bugs.debian.org/983379

Reported-by: Ritesh Raj Sarraf <[email protected]>
Signed-off-by: Johannes Berg <[email protected]>
Acked-By: Anton Ivanov <[email protected]>
Tested-By: Ritesh Raj Sarraf <[email protected]>
Signed-off-by: Richard Weinberger <[email protected]>
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