When _FORTIFY_SOURCE=2, glibc version is 2.35, and GCC version is
12.1.0, the compiler complains as follows:
In file included from /usr/include/features.h:490,
from /usr/include/bits/libc-header-start.h:33,
from /usr/include/stdint.h:26,
from /usr/lib/gcc/aarch64-unknown-linux-gnu/12.1.0/include/stdint.h:9,
from /home/alarm/q/var/qemu/include/qemu/osdep.h:94,
from ../util/vfio-helpers.c:13:
In function 'readlink',
inlined from 'sysfs_find_group_file' at ../util/vfio-helpers.c:116:9,
inlined from 'qemu_vfio_init_pci' at ../util/vfio-helpers.c:326:18,
inlined from 'qemu_vfio_open_pci' at ../util/vfio-helpers.c:517:9:
/usr/include/bits/unistd.h:119:10: error: argument 2 is null but the corresponding size argument 3 value is 4095 [-Werror=nonnull]
119 | return __glibc_fortify (readlink, __len, sizeof (char),
| ^~~~~~~~~~~~~~~
This error implies the allocated buffer can be NULL. Use
g_file_read_link(), which allocates buffer automatically to avoid the
error.
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
(cherry picked from commit dbdea0dbfe)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
12f0e61758