This is a note to let you know that I've just added the patch titled bus: mhi: host: Add alignment check for event ring read pointer to the 6.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: bus-mhi-host-add-alignment-check-for-event-ring-read-pointer.patch and it can be found in the queue-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From eff9704f5332a13b08fbdbe0f84059c9e7051d5f Mon Sep 17 00:00:00 2001 From: Krishna chaitanya chundru <quic_krichai@xxxxxxxxxxx> Date: Tue, 31 Oct 2023 15:21:05 +0530 Subject: bus: mhi: host: Add alignment check for event ring read pointer From: Krishna chaitanya chundru <quic_krichai@xxxxxxxxxxx> 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@xxxxxxxxxxxxxxx Signed-off-by: Krishna chaitanya chundru <quic_krichai@xxxxxxxxxxx> Reviewed-by: Jeffrey Hugo <quic_jhugo@xxxxxxxxxxx> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> Link: https://lore.kernel.org/r/20231031-alignment_check-v2-1-1441db7c5efd@xxxxxxxxxxx Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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) Patches currently in stable-queue which might be from quic_krichai@xxxxxxxxxxx are queue-6.6/bus-mhi-host-add-alignment-check-for-event-ring-read-pointer.patch