2023-12-03 15:52:10

by Fedor Pchelkin

[permalink] [raw]
Subject: [PATCH] scsi: megaraid_mm: do not access uninit kioc_list members

adapter->kioc_list is allocated using kmalloc_array() so its values are
left uninitialized. In a rare OOM case when dma_pool_alloc() fails in
mraid_mm_register_adp(), we should free the already allocated DMA pools
but comparing kioc->pthru32 with NULL doesn't guard from accessing uninit
memory.

Properly roll back in error case: free array members with lower indices.

Found by Linux Verification Center (linuxtesting.org).

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Fedor Pchelkin <[email protected]>
---
drivers/scsi/megaraid/megaraid_mm.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/scsi/megaraid/megaraid_mm.c b/drivers/scsi/megaraid/megaraid_mm.c
index c509440bd161..701eb5ee2a69 100644
--- a/drivers/scsi/megaraid/megaraid_mm.c
+++ b/drivers/scsi/megaraid/megaraid_mm.c
@@ -1001,12 +1001,10 @@ mraid_mm_register_adp(mraid_mmadp_t *lld_adp)

pthru_dma_pool_error:

- for (i = 0; i < lld_adp->max_kioc; i++) {
+ while (--i >= 0) {
kioc = adapter->kioc_list + i;
- if (kioc->pthru32) {
- dma_pool_free(adapter->pthru_dma_pool, kioc->pthru32,
- kioc->pthru32_h);
- }
+ dma_pool_free(adapter->pthru_dma_pool, kioc->pthru32,
+ kioc->pthru32_h);
}

memalloc_error:
--
2.43.0