From: Mike Crowe Date: Mon, 9 Sep 2019 13:16:16 +0000 (+0100) Subject: Intercept strncmp for glibc ld.so v2.28+ X-Git-Tag: VALGRIND_3_20_0~81 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=947388eb043ea1c44b37df94046e1eee790ad776;p=thirdparty%2Fvalgrind.git Intercept strncmp for glibc ld.so v2.28+ In glibc 5aad5f617892e75d91d4c8fb7594ff35b610c042 (first released in v2.28) a call to strncmp was added to dl-load.c:is_dst. This causes valgrind to complain about glibc's highly-optimised strncmp performing sixteen-byte reads on short strings in ld.so. Let's intercept strncmp in ld.so too so we use valgrind's simple version to avoid this problem. --- diff --git a/NEWS b/NEWS index dac9a1ce2a..4bf76608b7 100644 --- a/NEWS +++ b/NEWS @@ -35,6 +35,7 @@ bugzilla (https://bugs.kde.org/enter_bug.cgi?product=valgrind) rather than mailing the developers (or mailing lists) directly -- bugs that are not entered into bugzilla tend to get forgotten about or ignored. +434764 iconv_open causes ld.so v2.28+ to use optimised strncmp 446754 Improve error codes from alloc functions under memcheck 452274 memcheck crashes with Assertion 'sci->status.what == SsIdle' failed 452779 Valgrind fails to build on FreeBSD 13.0 with llvm-devel (15.0.0) diff --git a/shared/vg_replace_strmem.c b/shared/vg_replace_strmem.c index 3b42b3a871..5396e83be0 100644 --- a/shared/vg_replace_strmem.c +++ b/shared/vg_replace_strmem.c @@ -710,6 +710,8 @@ static inline void my_exit ( int x ) STRNCMP(VG_Z_LIBC_SONAME, __GI_strncmp) STRNCMP(VG_Z_LIBC_SONAME, __strncmp_sse2) STRNCMP(VG_Z_LIBC_SONAME, __strncmp_sse42) + STRNCMP(VG_Z_LD_LINUX_SO_2, strncmp) + STRNCMP(VG_Z_LD_LINUX_X86_64_SO_2, strncmp) #elif defined(VGO_freebsd) STRNCMP(VG_Z_LIBC_SONAME, strncmp)