[PATCH 6.1 0698/1146] staging: vme_user: Fix possible UAF in tsi148_dma_list_add

Greg Kroah-Hartman
2022-12-28T16:27:49Z

From: Gaosheng Cui <cuigaosheng1@huawei.com>

[ Upstream commit 357057ee55d3c99a5de5abe8150f7bca04f8e53b ]

Smatch report warning as follows:

drivers/staging/vme_user/vme_tsi148.c:1757 tsi148_dma_list_add() warn:
'&entry->list' not removed from list

In tsi148_dma_list_add(), the error path "goto err_dma" will not
remove entry->list from list->entries, but entry will be freed,
then list traversal may cause UAF.

Fix by removeing it from list->entries before free().

Fixes: b2383c90a9d6 ("vme: tsi148: fix first DMA item mapping")
Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Link: https://lore.kernel.org/r/20221117035914.2954454-1-cuigaosheng1@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/staging/vme_user/vme_tsi148.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/staging/vme_user/vme_tsi148.c b/drivers/staging/vme_user/vme_tsi148.c
index 020e0b3bce64..0171f46d1848 100644
--- a/drivers/staging/vme_user/vme_tsi148.c
+++ b/drivers/staging/vme_user/vme_tsi148.c
@@ -1751,6 +1751,7 @@ static int tsi148_dma_list_add(struct vme_dma_list *list,
return 0;

err_dma:
+ list_del(&entry->list);
err_dest:
err_source:
err_align:
--
2.35.1