Commit Graph

5 Commits

Author SHA1 Message Date
Joseph Myers
6d7e8eda9b Update copyright dates with scripts/update-copyrights 2023-01-06 21:14:39 +00:00
Adhemerval Zanella
40c112ed0d elf: Remove allocate use on _dl_debug_printf
The maximum number of directives is already limited by the maximum
value of iovec, and current padding usage on _dl_map_object_from_fd
specifies a value of 16 (2 times sizeof (void *)) in hexa, which is
less than the INT_STRLEN_BOUND(void *) (20 for LP64).

This works if pointers are larger than 8 bytes, for instance 16.
In this case the maximum padding would be 32 and the IFMTSIZE would
be 40.

The resulting code does use a slightly larger static stack, the
output of -fstack-usage (for x86_64):

 * master:
   dl-printf.c:35:1:_dl_debug_vdprintf     1344    dynamic

 * patch:
   dl-printf.c:36:1:_dl_debug_vdprintf     2416    static

However, there is an improvement in code generation:

 * master
   text    data     bss     dec     hex filename
   3309       0       0    3309     ced elf/dl-printf.os

 * patch
   text    data     bss     dec     hex filename
   3151       0       0    3151     c4f elf/dl-printf.os

Checked on x86_64-linux-gnu.

Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
2022-11-02 11:30:24 -03:00
Szabolcs Nagy
eef17d4d9f elf: Fix alloca size in _dl_debug_vdprintf
The alloca size did not consider the optional width parameter for
padding which could cause buffer underflow. The width is currently used
e.g. by _dl_map_object_from_fd which passes 2 * sizeof(void *) which
can be larger than the alloca buffer size on targets where
sizeof(void *) >= 2 * sizeof(unsigned long).

Even if large width is not used on existing targets it is better to fix
the formatting code to avoid surprises.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-10-28 11:16:09 +01:00
Adhemerval Zanella Netto
de477abcaa Use '%z' instead of '%Z' on printf functions
The Z modifier is a nonstandard synonymn for z (that predates z
itself) and compiler might issue an warning for in invalid
conversion specifier.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-09-22 08:48:04 -03:00
Florian Weimer
b693d75f0c elf: Split dl-printf.c from dl-misc.c
This allows to use different compiler flags for the diagnostics
code.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2022-01-14 20:17:05 +01:00