On 9/16/23 16:26, Dan Carpenter wrote:
On Sat, Sep 16, 2023 at 05:24:04PM +0300, Dan Carpenter wrote:
On Sat, Sep 16, 2023 at 01:41:43AM +0200, Danilo Krummrich wrote:
Hi Dan,
On 9/15/23 14:59, Dan Carpenter wrote:
The u_memcpya() function is supposed to return error pointers on
error. Returning NULL will lead to an Oops.
Fixes: 68132cc6d1bc ("nouveau/u_memcpya: use vmemdup_user")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
drivers/gpu/drm/nouveau/nouveau_drv.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/nouveau/nouveau_drv.h b/drivers/gpu/drm/nouveau/nouveau_drv.h
index 3666a7403e47..52a708a98915 100644
--- a/drivers/gpu/drm/nouveau/nouveau_drv.h
+++ b/drivers/gpu/drm/nouveau/nouveau_drv.h
@@ -193,7 +193,7 @@ u_memcpya(uint64_t user, unsigned int nmemb, unsigned int size)
size_t bytes;
if (unlikely(check_mul_overflow(nmemb, size, &bytes)))
- return NULL;
+ return ERR_PTR(-ENOMEM);
I plan to replace this function with an upcoming vmemdup_array_user() helper,
which returns -EOVERFLOW instead, hence mind using that?
Unless you disagree, no need to resubmit the patch, I can change it
before applying the patch.
Generally, I would say that ENOMEM is the correct error code. I feel
like someone thinks EOVERFLOW means integer overflow and that's not
correct. I means like if you pass a number higher than INT_MAX to
kstroint().
The most common error code for integer overflows is EINVAL because the
user passed invalid data.
I totally agree with that, and my choice would have been EINVAL as well. It's just
that it seems (v)memdup_array_user() [1] goes with that and hence I'd just go along.
[1] https://lore.kernel.org/lkml/93001a9f3f101be0f374080090f9c32df73ca773.1694202430.git.pstanner@xxxxxxxxxx/
regards,
dan carpenter
