Assert(valid) when ext_proc filter apply header mutations #27547

yanjunxiang-google · 2023-05-22T17:39:48Z

When ext_proc server sends back some header mutation settings which contain NULL characters, like /n, /r or /0, this will cause ext_proc filter ASSERT(valid) being fired up when Envoy is built in debug mode.
In release mode, the ASSERT is no-op, however, we should add an explicit check to avoid such kind of headers get injected into Envoy.

Assert(valid) when ext_proc filter apply header mutations.

Commit Message:
Additional Description:
Risk Level:
Testing:
Docs Changes:
Release Notes:
Platform Specific Features:
[Optional Runtime guard:]
[Optional Fixes #Issue]
[Optional Fixes commit #PR or SHA]
[Optional Deprecated:]
[Optional API Considerations:]

Signed-off-by: Yanjun Xiang <[email protected]>

yanjunxiang-google · 2023-05-22T20:24:59Z

/assign @yanavlasov @htuch @mpwarres @stevenzzzz

yanjunxiang-google · 2023-05-22T20:27:00Z

This is a fuzzer issue:

OSS fuzzer issue link: https://oss-fuzz.com/testcase-detail/5309367839490048

Accepting input from '[STDIN]'

| Usage for fuzzing: honggfuzz -P [flags] -- /mnt/scratch0/clusterfuzz/bot/builds/clusterfuzz-builds-honggfuzz_envoy_13d8ff3fd8b6e12ff5bbd32d951c40c9e1c6513f/revisions/ext_proc_unit_test_fuzz
| [2023-05-22 14:48:58.839][2428][critical][assert] [./envoy/http/header_map.h:71] assert failure: valid().
| AddressSanitizer:DEADLYSIGNAL
| =================================================================
| ==2428==ERROR: AddressSanitizer: ABRT on unknown address 0x05390000097c (pc 0x7a908660600b bp 0x7ffdaf9e1c90 sp 0x7ffdaf9e19b0 T0)
| SCARINESS: 10 (signal)
| #0 0x7a908660600b in raise /build/glibc-SzIz7B/glibc-2.31/sysdeps/unix/sysv/linux/raise.c:51:1
| #1 0x7a90865e5858 in abort /build/glibc-SzIz7B/glibc-2.31/stdlib/abort.c:79:7
| #2 0x1557b8f in Envoy::Http::LowerCaseString::LowerCaseString(std::__1::basic_string_view<char, std::__1::char_traits >) envoy/http/header_map.h:71:5
| #3 0x1685664 in Envoy::Extensions::HttpFilters::ExternalProcessing::MutationUtils::applyHeaderMutations(envoy::service::ext_proc::v3::HeaderMutation const&, Envoy::Http::HeaderMap&, bool, Envoy::Extensions::Filters::Common::MutationRules::Checker const&, Envoy::Stats::Counter&) /proc/self/cwd/source/extensions/filters/http/ext_proc/mutation_utils.cc:43:27
| #4 0x165dc14 in Envoy::Extensions::HttpFilters::ExternalProcessing::ProcessorState::handleHeadersResponse(envoy::service::ext_proc::v3::HeadersResponse const&) /proc/self/cwd/source/extensions/filters/http/ext_proc/processor_state.cc:87:31
| #5 0x163ae9e in Envoy::Extensions::HttpFilters::ExternalProcessing::Filter::onReceiveMessage(std::__1::unique_ptr<envoy::service::ext_proc::v3::ProcessingResponse, std::__1::default_deleteenvoy::service::ext_proc::v3::ProcessingResponse >&&) /proc/self/cwd/source/extensions/filters/http/ext_proc/ext_proc.cc:609:41
| #6 0x14c2fbf in operator() /proc/self/cwd/test/extensions/filters/http/ext_proc/unit_test_fuzz/ext_proc_unit_test_fuzz.cc:86:31
| #7 0x14c2fbf in __invoke<(lambda at test/extensions/filters/http/ext_proc/unit_test_fuzz/ext_proc_unit_test_fuzz.cc:82:28) &, envoy::service::ext_proc::v3::ProcessingRequest, bool> /usr/local/include/c++/v1/type_traits:3592:23
| #8 0x14c2fbf in __call<(lambda at test/extensions/filters/http/ext_proc/unit_test_fuzz/ext_proc_unit_test_fuzz.cc:82:28) &, envoy::service::ext_proc::v3::ProcessingRequest, bool> /usr/local/include/c++/v1/__functional/invoke.h:61:9
| #9 0x14c2fbf in operator() /usr/local/include/c++/v1/__functional/function.h:181:16
| #10 0x14c2fbf in std::__1::__function::__func<Envoy::Extensions::HttpFilters::ExtProc::UnitTestFuzz::TestOneProtoInput(envoy::extensions::filters::http::ext_proc::unit_test_fuzz::ExtProcUnitTestCase const&)::$_0::operator()(Envoy::Extensions::HttpFilters::ExternalProcessing::ExternalProcessorCallbacks&, envoy::config::core::v3::GrpcService const&, Envoy::StreamInfo::StreamInfo const&) const::'lambda'(envoy::service::ext_proc::v3::ProcessingRequest&&, bool), std::__1::allocator<Envoy::Extensions::HttpFilters::ExtProc::UnitTestFuzz::TestOneProtoInput(envoy::extensions::filters::http::ext_proc::unit_test_fuzz::ExtProcUnitTestCase const&)::$_0::operator()(Envoy::Extensions::HttpFilters::ExternalProcessing::ExternalProcessorCallbacks&, envoy::config::core::v3::GrpcService const&, Envoy::StreamInfo::StreamInfo const&) const::'lambda'(envoy::service::ext_proc::v3::ProcessingRequest&&, bool)>, void (envoy::service::ext_proc::v3::ProcessingRequest&&, bool)>::operator()(envoy::service::ext_proc::v3::ProcessingRequest&&, bool&&) /usr/local/include/c++/v1/__functional/function.h:355:12
| #11 0x1586861 in operator() /usr/local/include/c++/v1/__functional/function.h:508:16
| #12 0x1586861 in operator() /usr/local/include/c++/v1/__functional/function.h:1185:12
| #13 0x1586861 in ApplyImpl<const std::__1::function<void (envoy::service::ext_proc::v3::ProcessingRequest &&, bool)> &, std::__1::tuple<envoy::service::ext_proc::v3::ProcessingRequest &&, bool>, 0UL, 1UL> /proc/self/cwd/external/com_google_googletest/googlemock/include/gmock/internal/gmock-internal-utils.h:420:10
| #14 0x1586861 in Apply<const std::__1::function<void (envoy::service::ext_proc::v3::ProcessingRequest &&, bool)> &, std::__1::tuple<envoy::service::ext_proc::v3::ProcessingRequest &&, bool> > /proc/self/cwd/external/com_google_googletest/googlemock/include/gmock/internal/gmock-internal-utils.h:429:10
| #15 0x1586861 in Perform /proc/self/cwd/external/com_google_googletest/googlemock/include/gmock/gmock-actions.h:497:12
| #16 0x1586861 in PerformAction<void (envoy::service::ext_proc::v3::ProcessingRequest &&, bool)> /proc/self/cwd/external/com_google_googletest/googlemock/include/gmock/gmock-spec-builders.h:1441:12
| #17 0x1586861 in testing::internal::FunctionMocker<void (envoy::service::ext_proc::v3::ProcessingRequest&&, bool)>::UntypedPerformAction(void const*, void*) const /proc/self/cwd/external/com_google_googletest/googlemock/include/gmock/gmock-spec-builders.h:1556:12
| #18 0x50c8339 in testing::internal::UntypedFunctionMockerBase::UntypedInvokeWith(void*) /proc/self/cwd/external/com_google_googletest/googlemock/src/gmock-spec-builders.cc:452:24
| #19 0x1590021 in testing::internal::FunctionMocker<void (envoy::service::ext_proc::v3::ProcessingRequest&&, bool)>::Invoke(envoy::service::ext_proc::v3::ProcessingRequest&&, bool) /proc/self/cwd/external/com_google_googletest/googlemock/include/gmock/gmock-spec-builders.h:1593:15
| #20 0x1585db3 in Envoy::Extensions::HttpFilters::ExtProc::UnitTestFuzz::MockStream::send(envoy::service::ext_proc::v3::ProcessingRequest&&, bool) /proc/self/cwd/test/extensions/filters/http/ext_proc/unit_test_fuzz/mocks.h:20:3
| #21 0x162023f in Envoy::Extensions::HttpFilters::ExternalProcessing::Filter::onHeaders(Envoy::Extensions::HttpFilters::ExternalProcessing::ProcessorState&, Envoy::Http::RequestOrResponseHeaderMap&, bool) /proc/self/cwd/source/extensions/filters/http/ext_proc/ext_proc.cc:177:12
| #22 0x16225a6 in Envoy::Extensions::HttpFilters::ExternalProcessing::Filter::decodeHeaders(Envoy::Http::RequestHeaderMap&, bool) /proc/self/cwd/source/extensions/filters/http/ext_proc/ext_proc.cc:195:23
| #23 0x15c247b in Envoy::Http::FilterHeadersStatus Envoy::Extensions::HttpFilters::HttpFilterFuzzer::sendHeadersEnvoy::Http::StreamDecoderFilter(Envoy::Http::StreamDecoderFilter*, test::fuzz::HttpData const&, bool) /proc/self/cwd/test/extensions/filters/http/common/fuzz/http_filter_fuzzer.h:145:46
| #24 0x14d648f in void Envoy::Extensions::HttpFilters::HttpFilterFuzzer::runDataEnvoy::Http::StreamDecoderFilter(Envoy::Http::StreamDecoderFilter*, test::fuzz::HttpData const&) /proc/self/cwd/test/extensions/filters/http/common/fuzz/http_filter_fuzzer.h:102:31
| #25 0x14bf07a in TestOneProtoInput /proc/self/cwd/test/extensions/filters/http/ext_proc/unit_test_fuzz/ext_proc_unit_test_fuzz.cc:93:10
| #26 0x14bf07a in LLVMFuzzerTestOneInput /proc/self/cwd/test/extensions/filters/http/ext_proc/unit_test_fuzz/ext_proc_unit_test_fuzz.cc:38:1
| #27 0x519eedb in main
| #28 0x7a90865e7082 in __libc_start_main /build/glibc-SzIz7B/glibc-2.31/csu/libc-start.c:308:16
| #29 0x140142d in _start
|
| AddressSanitizer can not provide additional info.
| SUMMARY: AddressSanitizer: ABRT (/lib/x86_64-linux-gnu/libc.so.6+0x4300b) (BuildId: 1878e6b475720c7c51969e69ab2d276fae6d1dee)
| ==2428==ABORTING

Accepting input from '[STDIN]'
Usage for fuzzing: honggfuzz -P [flags] -- /mnt/scratch0/clusterfuzz/bot/builds/clusterfuzz-builds-honggfuzz_envoy_13d8ff3fd8b6e12ff5bbd32d951c40c9e1c6513f/revisions/ext_proc_unit_test_fuzz
[2023-05-22 14:48:58.839][2428][critical][assert] [./envoy/http/header_map.h:71] assert failure: valid().
AddressSanitizer:DEADLYSIGNAL

==2428==ERROR: AddressSanitizer: ABRT on unknown address 0x05390000097c (pc 0x7a908660600b bp 0x7ffdaf9e1c90 sp 0x7ffdaf9e19b0 T0)
SCARINESS: 10 (signal)
#0 0x7a908660600b in raise /build/glibc-SzIz7B/glibc-2.31/sysdeps/unix/sysv/linux/raise.c:51:1
#1 0x7a90865e5858 in abort /build/glibc-SzIz7B/glibc-2.31/stdlib/abort.c:79:7
#2 0x1557b8f in Envoy::Http::LowerCaseString::LowerCaseString(std::__1::basic_string_view<char, std::__1::char_traits >) envoy/http/header_map.h:71:5
#3 0x1685664 in Envoy::Extensions::HttpFilters::ExternalProcessing::MutationUtils::applyHeaderMutations(envoy::service::ext_proc::v3::HeaderMutation const&, Envoy::Http::HeaderMap&, bool, Envoy::Extensions::Filters::Common::MutationRules::Checker const&, Envoy::Stats::Counter&) /proc/self/cwd/source/extensions/filters/http/ext_proc/mutation_utils.cc:43:27
#4 0x165dc14 in Envoy::Extensions::HttpFilters::ExternalProcessing::ProcessorState::handleHeadersResponse(envoy::service::ext_proc::v3::HeadersResponse const&) /proc/self/cwd/source/extensions/filters/http/ext_proc/processor_state.cc:87:31
#5 0x163ae9e in Envoy::Extensions::HttpFilters::ExternalProcessing::Filter::onReceiveMessage(std::__1::unique_ptr<envoy::service::ext_proc::v3::ProcessingResponse, std::__1::default_deleteenvoy::service::ext_proc::v3::ProcessingResponse >&&) /proc/self/cwd/source/extensions/filters/http/ext_proc/ext_proc.cc:609:41
#6 0x14c2fbf in operator() /proc/self/cwd/test/extensions/filters/http/ext_proc/unit_test_fuzz/ext_proc_unit_test_fuzz.cc:86:31
#7 0x14c2fbf in __invoke<(lambda at test/extensions/filters/http/ext_proc/unit_test_fuzz/ext_proc_unit_test_fuzz.cc:82:28) &, envoy::service::ext_proc::v3::ProcessingRequest, bool> /usr/local/include/c++/v1/type_traits:3592:23
#8 0x14c2fbf in __call<(lambda at test/extensions/filters/http/ext_proc/unit_test_fuzz/ext_proc_unit_test_fuzz.cc:82:28) &, envoy::service::ext_proc::v3::ProcessingRequest, bool> /usr/local/include/c++/v1/__functional/invoke.h:61:9
#9 0x14c2fbf in operator() /usr/local/include/c++/v1/__functional/function.h:181:16
#10 0x14c2fbf in std::__1::__function::__func<Envoy::Extensions::HttpFilters::ExtProc::UnitTestFuzz::TestOneProtoInput(envoy::extensions::filters::http::ext_proc::unit_test_fuzz::ExtProcUnitTestCase const&)::$_0::operator()(Envoy::Extensions::HttpFilters::ExternalProcessing::ExternalProcessorCallbacks&, envoy::config::core::v3::GrpcService const&, Envoy::StreamInfo::StreamInfo const&) const::'lambda'(envoy::service::ext_proc::v3::ProcessingRequest&&, bool), std::__1::allocator<Envoy::Extensions::HttpFilters::ExtProc::UnitTestFuzz::TestOneProtoInput(envoy::extensions::filters::http::ext_proc::unit_test_fuzz::ExtProcUnitTestCase const&)::$_0::operator()(Envoy::Extensions::HttpFilters::ExternalProcessing::ExternalProcessorCallbacks&, envoy::config::core::v3::GrpcService const&, Envoy::StreamInfo::StreamInfo const&) const::'lambda'(envoy::service::ext_proc::v3::ProcessingRequest&&, bool)>, void (envoy::service::ext_proc::v3::ProcessingRequest&&, bool)>::operator()(envoy::service::ext_proc::v3::ProcessingRequest&&, bool&&) /usr/local/include/c++/v1/__functional/function.h:355:12
#11 0x1586861 in operator() /usr/local/include/c++/v1/__functional/function.h:508:16
#12 0x1586861 in operator() /usr/local/include/c++/v1/__functional/function.h:1185:12
#13 0x1586861 in ApplyImpl<const std::__1::function<void (envoy::service::ext_proc::v3::ProcessingRequest &&, bool)> &, std::__1::tuple<envoy::service::ext_proc::v3::ProcessingRequest &&, bool>, 0UL, 1UL> /proc/self/cwd/external/com_google_googletest/googlemock/include/gmock/internal/gmock-internal-utils.h:420:10
#14 0x1586861 in Apply<const std::__1::function<void (envoy::service::ext_proc::v3::ProcessingRequest &&, bool)> &, std::__1::tuple<envoy::service::ext_proc::v3::ProcessingRequest &&, bool> > /proc/self/cwd/external/com_google_googletest/googlemock/include/gmock/internal/gmock-internal-utils.h:429:10
#15 0x1586861 in Perform /proc/self/cwd/external/com_google_googletest/googlemock/include/gmock/gmock-actions.h:497:12
#16 0x1586861 in PerformAction<void (envoy::service::ext_proc::v3::ProcessingRequest &&, bool)> /proc/self/cwd/external/com_google_googletest/googlemock/include/gmock/gmock-spec-builders.h:1441:12
#17 0x1586861 in testing::internal::FunctionMocker<void (envoy::service::ext_proc::v3::ProcessingRequest&&, bool)>::UntypedPerformAction(void const*, void*) const /proc/self/cwd/external/com_google_googletest/googlemock/include/gmock/gmock-spec-builders.h:1556:12
#18 0x50c8339 in testing::internal::UntypedFunctionMockerBase::UntypedInvokeWith(void*) /proc/self/cwd/external/com_google_googletest/googlemock/src/gmock-spec-builders.cc:452:24
#19 0x1590021 in testing::internal::FunctionMocker<void (envoy::service::ext_proc::v3::ProcessingRequest&&, bool)>::Invoke(envoy::service::ext_proc::v3::ProcessingRequest&&, bool) /proc/self/cwd/external/com_google_googletest/googlemock/include/gmock/gmock-spec-builders.h:1593:15
#20 0x1585db3 in Envoy::Extensions::HttpFilters::ExtProc::UnitTestFuzz::MockStream::send(envoy::service::ext_proc::v3::ProcessingRequest&&, bool) /proc/self/cwd/test/extensions/filters/http/ext_proc/unit_test_fuzz/mocks.h:20:3
#21 0x162023f in Envoy::Extensions::HttpFilters::ExternalProcessing::Filter::onHeaders(Envoy::Extensions::HttpFilters::ExternalProcessing::ProcessorState&, Envoy::Http::RequestOrResponseHeaderMap&, bool) /proc/self/cwd/source/extensions/filters/http/ext_proc/ext_proc.cc:177:12
#22 0x16225a6 in Envoy::Extensions::HttpFilters::ExternalProcessing::Filter::decodeHeaders(Envoy::Http::RequestHeaderMap&, bool) /proc/self/cwd/source/extensions/filters/http/ext_proc/ext_proc.cc:195:23
#23 0x15c247b in Envoy::Http::FilterHeadersStatus Envoy::Extensions::HttpFilters::HttpFilterFuzzer::sendHeadersEnvoy::Http::StreamDecoderFilter(Envoy::Http::StreamDecoderFilter*, test::fuzz::HttpData const&, bool) /proc/self/cwd/test/extensions/filters/http/common/fuzz/http_filter_fuzzer.h:145:46
#24 0x14d648f in void Envoy::Extensions::HttpFilters::HttpFilterFuzzer::runDataEnvoy::Http::StreamDecoderFilter(Envoy::Http::StreamDecoderFilter*, test::fuzz::HttpData const&) /proc/self/cwd/test/extensions/filters/http/common/fuzz/http_filter_fuzzer.h:102:31
#25 0x14bf07a in TestOneProtoInput /proc/self/cwd/test/extensions/filters/http/ext_proc/unit_test_fuzz/ext_proc_unit_test_fuzz.cc:93:10
#26 0x14bf07a in LLVMFuzzerTestOneInput /proc/self/cwd/test/extensions/filters/http/ext_proc/unit_test_fuzz/ext_proc_unit_test_fuzz.cc:38:1
#27 0x519eedb in main
#28 0x7a90865e7082 in __libc_start_main /build/glibc-SzIz7B/glibc-2.31/csu/libc-start.c:308:16
#29 0x140142d in _start
AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: ABRT (/lib/x86_64-linux-gnu/libc.so.6+0x4300b) (BuildId: 1878e6b475720c7c51969e69ab2d276fae6d1dee)
==2428==ABORTING

yanjunxiang-google · 2023-05-22T20:28:26Z

Test case:

config {
grpc_service {
envoy_grpc {
cluster_name: "{"
}
}
stat_prefix: "sr..&......e.p"
mutation_rules {
allow_envoy {
}
disallow_all {
}
}
}
request {
}
response {
request_headers {
response {
header_mutation {
remove_headers: "\0 002"
remove_headers: "+d"
remove_headers: "\184017"
remove_headers: "+d"
}
}
}
dynamic_metadata {
}
}

htuch

Thanks, LGTM mostyl modulo comments. Needs a better description in commit message.

source/extensions/filters/http/ext_proc/mutation_utils.cc

stevenzzzz · 2023-05-23T13:20:20Z

LGTM, thanks for the catch.

yanavlasov

/wait

source/extensions/filters/http/ext_proc/mutation_utils.cc

source/extensions/filters/http/ext_proc/ext_proc.cc

Signed-off-by: Yanjun Xiang <[email protected]>

test/extensions/filters/http/ext_proc/mutation_utils_test.cc

Signed-off-by: Yanjun Xiang <[email protected]>

yanavlasov

/wait

test/extensions/filters/http/ext_proc/ext_proc_integration_test.cc

Signed-off-by: Yanjun Xiang <[email protected]>

yanjunxiang-google · 2023-05-24T17:34:55Z

/retest

htuch

LGTM modulo nit.

source/extensions/filters/http/ext_proc/ext_proc.cc

Signed-off-by: Yanjun Xiang <[email protected]>

…#27547) * ASSERT(valid()) when ext_proc filter apply header mutations. Signed-off-by: Yanjun Xiang <[email protected]> Signed-off-by: Ryan Eskin <[email protected]>

yanjunxiang-google added 2 commits May 22, 2023 17:36

ASSERT(valid()) when ext_proc filter apply header mutations.

6c498d6

Signed-off-by: Yanjun Xiang <[email protected]>

fix format

03a6a07

Signed-off-by: Yanjun Xiang <[email protected]>

yanjunxiang-google requested a review from snowp as a code owner May 22, 2023 17:39

follow up commit

c0463c0

Signed-off-by: Yanjun Xiang <[email protected]>

repokitteh-read-only bot assigned htuch, mpwarres, stevenzzzz and yanavlasov May 22, 2023

htuch reviewed May 23, 2023

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addressing comments

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yanjunxiang-google added 2 commits May 24, 2023 02:34

ENVOY_LOG_EVERY_POW_W

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null->invalid

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null -> invalid integration test

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status in message

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yanavlasov merged commit 2b3fbe5 into envoyproxy:main May 25, 2023

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Assert(valid) when ext_proc filter apply header mutations #27547

Assert(valid) when ext_proc filter apply header mutations #27547

yanjunxiang-google commented May 22, 2023 •

edited

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Assert(valid) when ext_proc filter apply header mutations #27547

Assert(valid) when ext_proc filter apply header mutations #27547

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yanjunxiang-google commented May 22, 2023 • edited Loading

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yanjunxiang-google commented May 22, 2023 • edited Loading

Accepting input from '[STDIN]'

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yanjunxiang-google commented May 22, 2023 •

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