1873745 - libFuzzer broken with undefined symbol: _ZN9dav1dfuzz24dav1d_set_cpu_flags_maskEj

Status: RESOLVED FIXED

(Core :: Fuzzing, defect)

Description

[Jesse Schwartzentruber (:truber)]

$ ./mach build && ./mach gtest -- '-*'
...
 0:04.72 Your build was successful!
One or more Android-only options will be ignored
 0:04.72 /home/truber/src/m/u/obj/ff-asan-fuzzing/dist/bin/firefox -unittest --gtest_death_test_style=threadsafe
XPCOMGlueLoad error for file /home/truber/src/m/u/obj/ff-asan-fuzzing/dist/bin/gtest/libxul.so:
/home/truber/src/m/u/obj/ff-asan-fuzzing/dist/bin/gtest/libxul.so: undefined symbol: _ZN9dav1dfuzz24dav1d_set_cpu_flags_maskEj
Couldn't load XPCOM.

Comment 1

[Jesse Schwartzentruber (:truber)]

Attachment: .mozconfig

Above error is from m-c b29d6ace45f4.

Applying f1a486575f57 in reverse fixes the build.

Comment 2

[BugBot [:suhaib / :marco/ :calixte]]

Set release status flags based on info from the regressing bug 1359918

Comment 3

[Mike Hommey [:glandium]]

The real cause is that bug 1533092 never worked, or nothing is calling whatever is calling dav1d_set_cpu_flags_mask, because the namespacing is definitely wrong: dav1d_fuzzer.c is compiled as C++ in a dav1dfuzz namespace, which puts things from cpu.h in the same namespace, but the corresponding definitions in cpu.c are not namespaced.

Comment 4

[Jesse Schwartzentruber (:truber)]

Attachment: Bug 1873745 - Fix Dav1d libFuzzer target r?decoder!

Comment 5

[Jesse Schwartzentruber (:truber)]

(In reply to Mike Hommey [:glandium] from comment #3)

The real cause is that bug 1533092 never worked, or nothing is calling whatever is calling dav1d_set_cpu_flags_mask, because the namespacing is definitely wrong: dav1d_fuzzer.c is compiled as C++ in a dav1dfuzz namespace, which puts things from cpu.h in the same namespace, but the corresponding definitions in cpu.c are not namespaced.

Thanks! That explains it. dav1d/dav1d.h contains extern "C" so is not affected, only cpu.h. And that symbol was only used by LLVMFuzzerInitialize which we were not calling.

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/34c419327301
Fix Dav1d libFuzzer target r=decoder

Comment 7

[Natalia Csoregi [:nataliaCs]]

https://hg.mozilla.org/mozilla-central/rev/34c419327301