misc/sys/cdefs.h: Create FORTIFY redirects for internal calls

The __REDIRECT* macros are creating aliases which may lead to unwanted
PLT entries when fortification is enabled.
To prevent these entries, the REDIRECT alias should be set to point to the
existing __GI_* aliases.
This is done transparently by creating a __REDIRECT_FORTIFY* version of
these macros, that can be overwritten internally when necessary.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
This commit is contained in:
Frédéric Bérat 2023-04-26 11:32:04 +02:00
parent 505c884aeb
commit eea000f6e6
2 changed files with 22 additions and 0 deletions

View File

@ -40,6 +40,20 @@ rtld_hidden_proto (__chk_fail)
#endif
#if defined SHARED
#if IS_IN (libc) && __USE_FORTIFY_LEVEL > 0 && defined __fortify_function
#undef __REDIRECT_FORTIFY
#define __REDIRECT_FORTIFY(name, proto, alias) \
__REDIRECT(name, proto, __GI_##alias)
#undef __REDIRECT_FORTIFY_NTH
#define __REDIRECT_FORTIFY_NTH(name, proto, alias) \
__REDIRECT_NTH(name, proto, __GI_##alias)
#endif
#endif /* defined SHARED */
#endif /* !defined _ISOMAC */
#endif

View File

@ -268,6 +268,14 @@
# define __ASMNAME(cname) __ASMNAME2 (__USER_LABEL_PREFIX__, cname)
# define __ASMNAME2(prefix, cname) __STRING (prefix) cname
#ifndef __REDIRECT_FORTIFY
#define __REDIRECT_FORTIFY __REDIRECT
#endif
#ifndef __REDIRECT_FORTIFY_NTH
#define __REDIRECT_FORTIFY_NTH __REDIRECT_NTH
#endif
/*
#elif __SOME_OTHER_COMPILER__