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Shigeru Yoshida
1cf9fc3b19
[ Upstream commit6f770b73d0] When a device performs DMA to a bounce buffer, KMSAN is unaware of the write and does not mark the data as initialized. When swiotlb_bounce() later copies the bounce buffer back to the original buffer, memcpy propagates the uninitialized shadow to the original buffer, causing false positive uninit-value reports. Fix this by calling kmsan_unpoison_memory() on the bounce buffer before copying it back in the DMA_FROM_DEVICE path, so that memcpy naturally propagates initialized shadow to the destination. Suggested-by: Alexander Potapenko <glider@google.com> Link: https://lore.kernel.org/CAG_fn=WUGta-paG1BgsGRoAR+fmuCgh3xo=R3XdzOt_-DqSdHw@mail.gmail.com/ Fixes:7ade4f1077("dma: kmsan: unpoison DMA mappings") Signed-off-by: Shigeru Yoshida <syoshida@redhat.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Link: https://lore.kernel.org/r/20260315082750.2375581-1-syoshida@redhat.com Signed-off-by: Sasha Levin <sashal@kernel.org>