diff options
| author | Stefan Hajnoczi <stefanha@redhat.com> | 2023-12-04 09:07:43 -0500 |
|---|---|---|
| committer | Michael S. Tsirkin <mst@redhat.com> | 2023-12-04 09:43:53 -0500 |
| commit | b8e0792449928943c15d1af9f63816911d139267 (patch) | |
| tree | 8a92221b1daff9d84fcdcb9c67ee9730ae80a025 /drivers/block | |
| parent | 1f475cd572ea77ae6474a17e693a96bca927efe9 (diff) | |
virtio_blk: fix snprintf truncation compiler warning
Commit 4e0400525691 ("virtio-blk: support polling I/O") triggers the
following gcc 13 W=1 warnings:
drivers/block/virtio_blk.c: In function ‘init_vq’:
drivers/block/virtio_blk.c:1077:68: warning: ‘%d’ directive output may be truncated writing between 1 and 11 bytes into a region of size 7 [-Wformat-truncation=]
1077 | snprintf(vblk->vqs[i].name, VQ_NAME_LEN, "req_poll.%d", i);
| ^~
drivers/block/virtio_blk.c:1077:58: note: directive argument in the range [-2147483648, 65534]
1077 | snprintf(vblk->vqs[i].name, VQ_NAME_LEN, "req_poll.%d", i);
| ^~~~~~~~~~~~~
drivers/block/virtio_blk.c:1077:17: note: ‘snprintf’ output between 11 and 21 bytes into a destination of size 16
1077 | snprintf(vblk->vqs[i].name, VQ_NAME_LEN, "req_poll.%d", i);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
This is a false positive because the lower bound -2147483648 is
incorrect. The true range of i is [0, num_vqs - 1] where 0 < num_vqs <
65536.
The code mixes int, unsigned short, and unsigned int types in addition
to using "%d" for an unsigned value. Use unsigned short and "%u"
consistently to solve the compiler warning.
Cc: Suwan Kim <suwan.kim027@gmail.com>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202312041509.DIyvEt9h-lkp@intel.com/
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20231204140743.1487843-1-stefanha@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'drivers/block')
| -rw-r--r-- | drivers/block/virtio_blk.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index d53d6aa8ee69..47556d8ccc32 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -1019,12 +1019,12 @@ static void virtblk_config_changed(struct virtio_device *vdev) static int init_vq(struct virtio_blk *vblk) { int err; - int i; + unsigned short i; vq_callback_t **callbacks; const char **names; struct virtqueue **vqs; unsigned short num_vqs; - unsigned int num_poll_vqs; + unsigned short num_poll_vqs; struct virtio_device *vdev = vblk->vdev; struct irq_affinity desc = { 0, }; @@ -1068,13 +1068,13 @@ static int init_vq(struct virtio_blk *vblk) for (i = 0; i < num_vqs - num_poll_vqs; i++) { callbacks[i] = virtblk_done; - snprintf(vblk->vqs[i].name, VQ_NAME_LEN, "req.%d", i); + snprintf(vblk->vqs[i].name, VQ_NAME_LEN, "req.%u", i); names[i] = vblk->vqs[i].name; } for (; i < num_vqs; i++) { callbacks[i] = NULL; - snprintf(vblk->vqs[i].name, VQ_NAME_LEN, "req_poll.%d", i); + snprintf(vblk->vqs[i].name, VQ_NAME_LEN, "req_poll.%u", i); names[i] = vblk->vqs[i].name; } |