| Message ID | 20230130133217.497398-1-siddhesh@sourceware.org |
|---|---|
| State | New |
| Headers | show |
| Series | cdefs: Limit definition of fortification macros | expand |
* Siddhesh Poyarekar: > Define the __glibc_fortify and other macros only when __FORTIFY_LEVEL > > 0. This has the effect of not defining these macros on older C90 > compilers that do not have support for variable length argument lists. > > Also trim off the trailing backslashes from the definition of > __glibc_fortify and __glibc_fortify_n macros. > > Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org> > --- > > Only tested for sanity. Florian, can you please verify that this > resolves the original problem? > > misc/sys/cdefs.h | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/misc/sys/cdefs.h b/misc/sys/cdefs.h > index 66d6702123..c37a3ff637 100644 > --- a/misc/sys/cdefs.h > +++ b/misc/sys/cdefs.h > @@ -152,6 +152,7 @@ > # define __glibc_objsize(__o) __bos (__o) > #endif > > +#if __USE_FORTIFY_LEVEL > 0 > /* Compile time conditions to choose between the regular, _chk and _chk_warn > variants. These conditions should get evaluated to constant and optimized > away. */ > @@ -187,7 +188,7 @@ > ? __ ## f ## _alias (__VA_ARGS__) \ > : (__glibc_unsafe_len (__l, __s, __osz) \ > ? __ ## f ## _chk_warn (__VA_ARGS__, __osz) \ > - : __ ## f ## _chk (__VA_ARGS__, __osz))) \ > + : __ ## f ## _chk (__VA_ARGS__, __osz))) > > /* Fortify function f, where object size argument passed to f is the number of > elements and not total size. */ > @@ -197,7 +198,8 @@ > ? __ ## f ## _alias (__VA_ARGS__) \ > : (__glibc_unsafe_len (__l, __s, __osz) \ > ? __ ## f ## _chk_warn (__VA_ARGS__, (__osz) / (__s)) \ > - : __ ## f ## _chk (__VA_ARGS__, (__osz) / (__s)))) \ > + : __ ## f ## _chk (__VA_ARGS__, (__osz) / (__s)))) > +#endif > > #if __GNUC_PREREQ (4,3) > # define __warnattr(msg) __attribute__((__warning__ (msg))) Seems reasonable, thanks. I believe it works with those old compilers. Reviewed-by: Florian Weimer <fweimer@redhat.com> Florian
diff --git a/misc/sys/cdefs.h b/misc/sys/cdefs.h index 66d6702123..c37a3ff637 100644 --- a/misc/sys/cdefs.h +++ b/misc/sys/cdefs.h @@ -152,6 +152,7 @@ # define __glibc_objsize(__o) __bos (__o) #endif +#if __USE_FORTIFY_LEVEL > 0 /* Compile time conditions to choose between the regular, _chk and _chk_warn variants. These conditions should get evaluated to constant and optimized away. */ @@ -187,7 +188,7 @@ ? __ ## f ## _alias (__VA_ARGS__) \ : (__glibc_unsafe_len (__l, __s, __osz) \ ? __ ## f ## _chk_warn (__VA_ARGS__, __osz) \ - : __ ## f ## _chk (__VA_ARGS__, __osz))) \ + : __ ## f ## _chk (__VA_ARGS__, __osz))) /* Fortify function f, where object size argument passed to f is the number of elements and not total size. */ @@ -197,7 +198,8 @@ ? __ ## f ## _alias (__VA_ARGS__) \ : (__glibc_unsafe_len (__l, __s, __osz) \ ? __ ## f ## _chk_warn (__VA_ARGS__, (__osz) / (__s)) \ - : __ ## f ## _chk (__VA_ARGS__, (__osz) / (__s)))) \ + : __ ## f ## _chk (__VA_ARGS__, (__osz) / (__s)))) +#endif #if __GNUC_PREREQ (4,3) # define __warnattr(msg) __attribute__((__warning__ (msg)))
Define the __glibc_fortify and other macros only when __FORTIFY_LEVEL > 0. This has the effect of not defining these macros on older C90 compilers that do not have support for variable length argument lists. Also trim off the trailing backslashes from the definition of __glibc_fortify and __glibc_fortify_n macros. Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org> --- Only tested for sanity. Florian, can you please verify that this resolves the original problem? misc/sys/cdefs.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)