On other arches stpcpy () is intercepted for both libc.so and ld.so. But not on arm64, where it is only intercepted for libc.so. This can cause memcheck warnings about the use of stpcpy () in ld.so when called through dlopen () because ld.so contains its own copy of that functions. ==3145== Use of uninitialised value of size 8 ==3145== at 0x4018014: stpcpy (strcpy.S:158) ==3145== by 0x4007607: _dl_dst_substitute (dl-load.c:327) ==3145== by 0x40081EB: _dl_map_object (dl-load.c:2173) ==3145== by 0x4011ADB: dl_open_worker (dl-open.c:217) ==3145== by 0x4A2C047: _dl_catch_exception (dl-error-skeleton.c:196) ==3145== by 0x40116B7: _dl_open (dl-open.c:588) ==3145== by 0x48F1093: dlopen_doit (dlopen.c:66) ==3145== by 0x4A2C047: _dl_catch_exception (dl-error-skeleton.c:196) ==3145== by 0x4A2C0EF: _dl_catch_error (dl-error-skeleton.c:215) ==3145== by 0x48F17DF: _dlerror_run (dlerror.c:163) ==3145== by 0x48F1133: dlopen@@GLIBC_2.17 (dlopen.c:87) The following proposed patch gets rid of this warning: diff --git a/include/pub_tool_redir.h b/include/pub_tool_redir.h index c97941ff4..15ba67fdb 100644 --- a/include/pub_tool_redir.h +++ b/include/pub_tool_redir.h @@ -313,7 +313,9 @@ #define VG_Z_LD_SO_1 ldZdsoZd1 // ld.so.1 #define VG_U_LD_SO_1 "ld.so.1" +#define VG_Z_LD_LINUX_AARCH64_SO_1 ldZhlinuxZhaarch64ZdsoZd1 #define VG_U_LD_LINUX_AARCH64_SO_1 "ld-linux-aarch64.so.1" + #define VG_U_LD_LINUX_ARMHF_SO_3 "ld-linux-armhf.so.3" #endif diff --git a/shared/vg_replace_strmem.c b/shared/vg_replace_strmem.c index 89a7dccb7..19143cf15 100644 --- a/shared/vg_replace_strmem.c +++ b/shared/vg_replace_strmem.c @@ -1160,6 +1160,7 @@ static inline void my_exit ( int x ) STPCPY(VG_Z_LIBC_SONAME, __stpcpy_sse2_unaligned) STPCPY(VG_Z_LD_LINUX_SO_2, stpcpy) STPCPY(VG_Z_LD_LINUX_X86_64_SO_2, stpcpy) + STPCPY(VG_Z_LD_LINUX_AARCH64_SO_1,stpcpy) #elif defined(VGO_darwin) //STPCPY(VG_Z_LIBC_SONAME, stpcpy)
Briefly discussed on irc and now committed as: commit 89423f5d8ba05a099c2c62227a00a4f4eec59eb3 Author: Mark Wielaard <mark@klomp.org> Date: Tue May 7 21:20:04 2019 +0200 Intercept stpcpy also in ld.so for arm64 On other arches stpcpy () is intercepted for both libc.so and ld.so. But not on arm64, where it is only intercepted for libc.so. This can cause memcheck warnings about the use of stpcpy () in ld.so when called through dlopen () because ld.so contains its own copy of that functions. Fix by introducing VG_Z_LD_LINUX_AARCH64_SO_1 (the encoded name of ld.so on arm64) and using that in vg_replace_strmem.c to intercept stpcpy. https://bugs.kde.org/show_bug.cgi?id=407307