6.6-stable review patch. If anyone has any objections, please let me know.
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From: Krishna chaitanya chundru quic_krichai@quicinc.com
commit eff9704f5332a13b08fbdbe0f84059c9e7051d5f upstream.
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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/bus/mhi/host/main.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/bus/mhi/host/main.c +++ b/drivers/bus/mhi/host/main.c @@ -268,7 +268,8 @@ static void mhi_del_ring_element(struct
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_ring_element) - 1)); }
int mhi_destroy_device(struct device *dev, void *data)