Re: [PATCH] Apply asm redirections in syslog.h before first use [BZ #27087]

[Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>]

On 16/11/22 12:08, Tulio Magno Quites Machado Filho via Libc-alpha wrote:
> From: Tulio Magno Quites Machado Filho <tuliom@redhat.com>
> 
> Similar to d0fa09a770, but for syslog.h when _FORTIFY_SOURCE > 0.
> Fixes [BZ #27087] by applying long double-related asm redirections
> before using functions in bits/syslog.h.
> 
> Tested with build-many-glibcs.py.

LGTM, thanks.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

> ---
>  misc/bits/syslog.h | 18 ++++++++++++++----
>  misc/sys/syslog.h  | 10 +++++-----
>  2 files changed, 19 insertions(+), 9 deletions(-)
> 
> diff --git a/misc/bits/syslog.h b/misc/bits/syslog.h
> index fd30dd3114..916d2b6f12 100644
> --- a/misc/bits/syslog.h
> +++ b/misc/bits/syslog.h
> @@ -24,6 +24,20 @@
>  extern void __syslog_chk (int __pri, int __flag, const char *__fmt, ...)
>       __attribute__ ((__format__ (__printf__, 3, 4)));
>  
> +#ifdef __USE_MISC
> +extern void __vsyslog_chk (int __pri, int __flag, const char *__fmt,
> +			   __gnuc_va_list __ap)
> +     __attribute__ ((__format__ (__printf__, 3, 0)));
> +#endif
> +
> +#include <bits/floatn.h>
> +#if defined __LDBL_COMPAT || __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 1
> +# include <bits/syslog-ldbl.h>
> +#endif
> +
> +/* The following functions must be used only after applying all asm
> +   redirections, e.g. long double asm redirections.  */
> +
>  #ifdef __va_arg_pack
>  __fortify_function void
>  syslog (int __pri, const char *__fmt, ...)
> @@ -37,10 +51,6 @@ syslog (int __pri, const char *__fmt, ...)
>  
>  
>  #ifdef __USE_MISC
> -extern void __vsyslog_chk (int __pri, int __flag, const char *__fmt,
> -			   __gnuc_va_list __ap)
> -     __attribute__ ((__format__ (__printf__, 3, 0)));
> -
>  __fortify_function void
>  vsyslog (int __pri, const char *__fmt, __gnuc_va_list __ap)
>  {
> diff --git a/misc/sys/syslog.h b/misc/sys/syslog.h
> index d933fea104..3888153ed2 100644
> --- a/misc/sys/syslog.h
> +++ b/misc/sys/syslog.h
> @@ -205,11 +205,11 @@ extern void vsyslog (int __pri, const char *__fmt, __gnuc_va_list __ap)
>  /* Define some macros helping to catch buffer overflows.  */
>  #if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function
>  # include <bits/syslog.h>
> -#endif
> -
> -#include <bits/floatn.h>
> -#if defined __LDBL_COMPAT || __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 1
> -# include <bits/syslog-ldbl.h>
> +#else
> +# include <bits/floatn.h>
> +# if defined __LDBL_COMPAT || __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 1
> +#  include <bits/syslog-ldbl.h>
> +# endif
>  #endif
>  
>  __END_DECLS