From: Krishna chaitanya chundru <quic_krichai@quicinc.com> mainline inclusion from mainline-v6.8-rc1 commit eff9704f5332a13b08fbdbe0f84059c9e7051d5f category: bugfix bugzilla: 189679 CVE: CVE-2023-52494 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... ------------------------------------------------------ Though we do check the event ring read pointer by "is_valid_ring_ptr" to make sure it is in the buffer range, but there is another risk the pointer may be not aligned. Since we are expecting event ring elements are 128 bits(struct mhi_ring_element) aligned, an unaligned read pointer could lead to multiple issues like DoS or ring buffer memory corruption. So add a alignment check for event ring read pointer. Fixes: ec32332df764 ("bus: mhi: core: Sanity check values from remote device before use") cc: stable@vger.kernel.org Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com> Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Link: https://lore.kernel.org/r/20231031-alignment_check-v2-1-1441db7c5efd@quicinc... Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> conflicts: drivers/bus/mhi/host/main.c Signed-off-by: Cai Xinchen <caixinchen1@huawei.com> --- drivers/bus/mhi/host/main.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/bus/mhi/host/main.c b/drivers/bus/mhi/host/main.c index 614dd287cb4f..82d6e9e8bddf 100644 --- a/drivers/bus/mhi/host/main.c +++ b/drivers/bus/mhi/host/main.c @@ -222,7 +222,8 @@ static void mhi_del_ring_element(struct mhi_controller *mhi_cntrl, static bool is_valid_ring_ptr(struct mhi_ring *ring, dma_addr_t addr) { - return addr >= ring->iommu_base && addr < ring->iommu_base + ring->len; + return addr >= ring->iommu_base && addr < ring->iommu_base + ring->len && + !(addr & (sizeof(struct mhi_tre) - 1)); } int mhi_destroy_device(struct device *dev, void *data) -- 2.34.1