From: Akihiko Odaki <akihiko.od...@daynix.com>
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.od...@daynix.com>
Reviewed-by: Philippe Mathieu-Daudé <phi...@linaro.org>
Reviewed-by: Cédric Le Goater <c...@redhat.com>
Signed-off-by: Cédric Le Goater <c...@redhat.com>
---
util/vfio-helpers.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/util/vfio-helpers.c b/util/vfio-helpers.c
index 2d8af38f886a..f8bab46c68fa 100644
--- a/util/vfio-helpers.c
+++ b/util/vfio-helpers.c
@@ -106,15 +106,17 @@ struct QEMUVFIOState {
*/
static char *sysfs_find_group_file(const char *device, Error **errp)
{
+ g_autoptr(GError) gerr = NULL;
char *sysfs_link;
char *sysfs_group;
char *p;
char *path = NULL;
sysfs_link = g_strdup_printf("/sys/bus/pci/devices/%s/iommu_group",
device);
- sysfs_group = g_malloc0(PATH_MAX);
- if (readlink(sysfs_link, sysfs_group, PATH_MAX - 1) == -1) {
- error_setg_errno(errp, errno, "Failed to find iommu group sysfs path");
+ sysfs_group = g_file_read_link(sysfs_link, &gerr);
+ if (gerr) {
+ error_setg(errp, "Failed to find iommu group sysfs path: %s",
+ gerr->message);
goto out;
}
p = strrchr(sysfs_group, '/');
--
2.40.1
