6.6-stable review patch. If anyone has any objections, please let me know.
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From: Pavel Sakharov p.sakharov@ispras.ru
[ Upstream commit 2295bd846765c766701e666ed2e4b35396be25e6 ]
If due to a memory allocation failure mock_chain() returns NULL, it is passed to dma_fence_enable_sw_signaling() resulting in NULL pointer dereference there.
Call dma_fence_enable_sw_signaling() only if mock_chain() succeeds.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: d62c43a953ce ("dma-buf: Enable signaling on fence for selftests") Signed-off-by: Pavel Sakharov p.sakharov@ispras.ru Reviewed-by: Christian König christian.koenig@amd.com Signed-off-by: Christian König christian.koenig@amd.com Link: https://patchwork.freedesktop.org/patch/msgid/20240319231527.1821372-1-p.sak... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/dma-buf/st-dma-fence-chain.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/dma-buf/st-dma-fence-chain.c b/drivers/dma-buf/st-dma-fence-chain.c index c0979c8049b5a..661de4add4c72 100644 --- a/drivers/dma-buf/st-dma-fence-chain.c +++ b/drivers/dma-buf/st-dma-fence-chain.c @@ -84,11 +84,11 @@ static int sanitycheck(void *arg) return -ENOMEM;
chain = mock_chain(NULL, f, 1); - if (!chain) + if (chain) + dma_fence_enable_sw_signaling(chain); + else err = -ENOMEM;
- dma_fence_enable_sw_signaling(chain); - dma_fence_signal(f); dma_fence_put(f);