diff mbox series

[net-next,3/3] accel/qaic: Pass string literal as format argument of alloc_workqueue()

Message ID 20241011-string-thing-v1-3-acc506568033@kernel.org
State Accepted
Commit 11fc5ce6e2a6316b7d02746c035ee1e51bf10718
Headers show
Series [net-next,1/3] net: dsa: microchip: copy string using strscpy | expand

Commit Message

Simon Horman Oct. 11, 2024, 9:57 a.m. UTC
Recently I noticed that both gcc-14 and clang-18 report that passing
a non-string literal as the format argument of alloc_workqueue()
is potentially insecure.

E.g. clang-18 says:

.../qaic_drv.c:61:23: warning: format string is not a string literal (potentially insecure) [-Wformat-security]
   61 |         wq = alloc_workqueue(fmt, WQ_UNBOUND, 0);
      |                              ^~~
.../qaic_drv.c:61:23: note: treat the string as an argument to avoid this
   61 |         wq = alloc_workqueue(fmt, WQ_UNBOUND, 0);
      |                              ^
      |                              "%s",

It is always the case where the contents of fmt is safe to pass as the
format argument. That is, in my understanding, it never contains any
format escape sequences.

But, it seems better to be safe than sorry. And, as a bonus, compiler
output becomes less verbose by addressing this issue as suggested by
clang-18.

Also, change the name of the parameter of qaicm_wq_init from
fmt to name to better reflect it's purpose.

Compile tested only.

Signed-off-by: Simon Horman <horms@kernel.org>
---
 drivers/accel/qaic/qaic_drv.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Jeffrey Hugo Oct. 18, 2024, 7:38 p.m. UTC | #1
On 10/11/2024 3:57 AM, Simon Horman wrote:
> Recently I noticed that both gcc-14 and clang-18 report that passing
> a non-string literal as the format argument of alloc_workqueue()
> is potentially insecure.
> 
> E.g. clang-18 says:
> 
> .../qaic_drv.c:61:23: warning: format string is not a string literal (potentially insecure) [-Wformat-security]
>     61 |         wq = alloc_workqueue(fmt, WQ_UNBOUND, 0);
>        |                              ^~~
> .../qaic_drv.c:61:23: note: treat the string as an argument to avoid this
>     61 |         wq = alloc_workqueue(fmt, WQ_UNBOUND, 0);
>        |                              ^
>        |                              "%s",
> 
> It is always the case where the contents of fmt is safe to pass as the
> format argument. That is, in my understanding, it never contains any
> format escape sequences.
> 
> But, it seems better to be safe than sorry. And, as a bonus, compiler
> output becomes less verbose by addressing this issue as suggested by
> clang-18.
> 
> Also, change the name of the parameter of qaicm_wq_init from
> fmt to name to better reflect it's purpose.
> 
> Compile tested only.
> 
> Signed-off-by: Simon Horman <horms@kernel.org>

Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Tested-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
diff mbox series

Patch

diff --git a/drivers/accel/qaic/qaic_drv.c b/drivers/accel/qaic/qaic_drv.c
index bf10156c334e..30e6bf7897bd 100644
--- a/drivers/accel/qaic/qaic_drv.c
+++ b/drivers/accel/qaic/qaic_drv.c
@@ -53,12 +53,12 @@  static void qaicm_wq_release(struct drm_device *dev, void *res)
 	destroy_workqueue(wq);
 }
 
-static struct workqueue_struct *qaicm_wq_init(struct drm_device *dev, const char *fmt)
+static struct workqueue_struct *qaicm_wq_init(struct drm_device *dev, const char *name)
 {
 	struct workqueue_struct *wq;
 	int ret;
 
-	wq = alloc_workqueue(fmt, WQ_UNBOUND, 0);
+	wq = alloc_workqueue("%s", WQ_UNBOUND, 0, name);
 	if (!wq)
 		return ERR_PTR(-ENOMEM);
 	ret = drmm_add_action_or_reset(dev, qaicm_wq_release, wq);