linux-kernel - [PATCH] dmaengine: ti: edma: Fix memory allocation size for queue_priority

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250829131346.3697633-1-anders.roxell@linaro.org>
Date: Fri, 29 Aug 2025 15:13:46 +0200
From: Anders Roxell <anders.roxell@...aro.org>
To: peter.ujfalusi@...il.com,
	vkoul@...nel.org,
	nathan@...nel.org
Cc: dmaengine@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	llvm@...ts.linux.dev,
	dan.carpenter@...aro.org,
	arnd@...db.de,
	benjamin.copeland@...aro.org,
	Anders Roxell <anders.roxell@...aro.org>
Subject: [PATCH] dmaengine: ti: edma: Fix memory allocation size for queue_priority_map

Fix a critical memory allocation bug in edma_setup_from_hw() where
queue_priority_map was allocated with insufficient memory. The code
declared queue_priority_map as s8 (*)[2] (pointer to array of 2 s8), but
allocated memory using sizeof(s8) instead of sizeof(s8[2]).

This caused out-of-bounds memory writes when accessing:
  queue_priority_map[i][0] = i;
  queue_priority_map[i][1] = i;

The bug manifested as kernel crashes with "Oops - undefined instruction"
on ARM platforms (BeagleBoard-X15) during EDMA driver probe, as the
memory corruption triggered kernel hardening features on Clang.

Change the allocation from:
  devm_kcalloc(dev, ecc->num_tc + 1, sizeof(s8), GFP_KERNEL)
to this:
  devm_kcalloc(dev, ecc->num_tc + 1, sizeof(s8[2]), GFP_KERNEL)

This ensures proper allocation of (ecc->num_tc + 1) * 2 bytes to match
the expected 2D array structure.

Fixes: 2b6b3b742019 ("ARM/dmaengine: edma: Merge the two drivers under drivers/dma/")
Signed-off-by: Anders Roxell <anders.roxell@...aro.org>
---
 drivers/dma/ti/edma.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/dma/ti/edma.c b/drivers/dma/ti/edma.c
index 3ed406f08c44..8f9b65e4bc87 100644
--- a/drivers/dma/ti/edma.c
+++ b/drivers/dma/ti/edma.c
@@ -2064,7 +2064,7 @@ static int edma_setup_from_hw(struct device *dev, struct edma_soc_info *pdata,
 	 * priority. So Q0 is the highest priority queue and the last queue has
 	 * the lowest priority.
 	 */
-	queue_priority_map = devm_kcalloc(dev, ecc->num_tc + 1, sizeof(s8),
+	queue_priority_map = devm_kcalloc(dev, ecc->num_tc + 1, sizeof(s8[2]),
 					  GFP_KERNEL);
 	if (!queue_priority_map)
 		return -ENOMEM;
-- 
2.50.1