6.12-stable review patch. If anyone has any objections, please let me know.
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From: Youssef Samir quic_yabdulra@quicinc.com
[ Upstream commit 11f08c30a3e4157305ba692f1d44cca5fc9a8fca ]
Currently, if find_and_map_user_pages() takes a DMA xfer request from the user with a length field set to 0, or in a rare case, the host receives QAIC_TRANS_DMA_XFER_CONT from the device where resources->xferred_dma_size is equal to the requested transaction size, the function will return 0 before allocating an sgt or setting the fields of the dma_xfer struct. In that case, encode_addr_size_pairs() will try to access the sgt which will lead to a general protection fault.
Return an EINVAL in case the user provides a zero-sized ALP, or the device requests continuation after all of the bytes have been transferred.
Fixes: 96d3c1cadedb ("accel/qaic: Clean up integer overflow checking in map_user_pages()") Signed-off-by: Youssef Samir quic_yabdulra@quicinc.com Signed-off-by: Youssef Samir youssef.abdulrahman@oss.qualcomm.com Reviewed-by: Jeff Hugo jeff.hugo@oss.qualcomm.com Reviewed-by: Carl Vanderlip carl.vanderlip@oss.qualcomm.com Signed-off-by: Jeff Hugo jeff.hugo@oss.qualcomm.com Link: https://lore.kernel.org/r/20251007122320.339654-1-youssef.abdulrahman@oss.qu... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/accel/qaic/qaic_control.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/accel/qaic/qaic_control.c b/drivers/accel/qaic/qaic_control.c index d8bdab69f8009..b86a8e48e731b 100644 --- a/drivers/accel/qaic/qaic_control.c +++ b/drivers/accel/qaic/qaic_control.c @@ -407,7 +407,7 @@ static int find_and_map_user_pages(struct qaic_device *qdev, return -EINVAL; remaining = in_trans->size - resources->xferred_dma_size; if (remaining == 0) - return 0; + return -EINVAL;
if (check_add_overflow(xfer_start_addr, remaining, &end)) return -EINVAL;