[PATCH net] net: alacritech: fix dma_free_coherent() in error path

[PATCH net] net: alacritech: fix dma_free_coherent() in error path

[Thomas Fourier]

In slic_init_stat_queue(), a series of coherent buffers is allocated
with the length size. The size is then stored in stq->mem_size for
normal deallocation. However, in the error path, stq->mem_size is also
used but is not initialized. This error may leave the freed buffers
mapped, leaking a resource and allowing the device to access freed
memory.

Change the length in error path to size.

Fixes: 60c140df15db ("net: ethernet: slicoss: add slicoss gigabit ethernet driver")
Cc: <stable@vger.kernel.org>
Signed-off-by: Thomas Fourier <fourier.thomas@gmail.com>
---
 drivers/net/ethernet/alacritech/slicoss.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/alacritech/slicoss.c b/drivers/net/ethernet/alacritech/slicoss.c
index c1949ca060ca..311a9d1d9071 100644
--- a/drivers/net/ethernet/alacritech/slicoss.c
+++ b/drivers/net/ethernet/alacritech/slicoss.c
@@ -813,7 +813,7 @@ static int slic_init_stat_queue(struct slic_device *sdev)
 
 free_descs:
 	while (i--) {
-		dma_free_coherent(&sdev->pdev->dev, stq->mem_size,
+		dma_free_coherent(&sdev->pdev->dev, size,
 				  stq->descs[i] - stq->addr_offset[i],
 				  stq->paddr[i] - stq->addr_offset[i]);
 	}
-- 
2.43.0

Re: [PATCH net] net: alacritech: fix dma_free_coherent() in error path

[netdev-bot+sinfo]

Hi!

This is an automated message. This series looks like a fix, but its
commit messages seem to be missing some information:

 - How the issue was discovered, e.g. hit in production, hit during
   development, syzbot report, manual code inspection, LLM or static
   analysis tool scan.

 - Whether the issue was actually triggered, or is only theoretical
   (e.g. found by code inspection). If it was triggered please include
   the symptoms, like the stack trace or error messages.

 - What hardware the change was tested on. For driver fixes please
   mention the device (and if relevant firmware version) used for
   testing, or say that the change was not tested on real hardware.

Please do not repost the series just to address the above. Instead,
reply to this email with the missing information, so that reviewers
can take it into account. If the series needs another revision for
other reasons, please include the information in the commit messages
then.

The evaluation is done by an LLM so it may be wrong, if you think
that is the case please reply and explain.