5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Daisuke Matsuda commit 9da70a43b5fea60d758137f7f0ccfe19356cb5bb upstream. The trailing byte path in altera_cvp_send_block() dereferences a u32 pointer even when only 1-3 bytes remain in the input buffer. If the buffer ends at a page or scatterlist boundary, this can read past the valid image data and fault. Copy the remaining bytes into a zero-initialized u32 before writing the final word so only valid bytes are read from the input buffer. Fixes: 34d1dc17ce97 ("fpga manager: Add Altera CvP driver") Cc: stable@vger.kernel.org Signed-off-by: Daisuke Matsuda Reviewed-by: Xu Yilun Link: https://lore.kernel.org/r/20260723081912.74082-1-dskmtsd@gmail.com Signed-off-by: Xu Yilun Signed-off-by: Greg Kroah-Hartman --- drivers/fpga/altera-cvp.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) --- a/drivers/fpga/altera-cvp.c +++ b/drivers/fpga/altera-cvp.c @@ -16,6 +16,7 @@ #include #include #include +#include #define CVP_BAR 0 /* BAR used for data transfer in memory mode */ #define CVP_DUMMY_WR 244 /* dummy writes to clear CvP state machine */ @@ -265,7 +266,7 @@ static int altera_cvp_v2_wait_for_credit static int altera_cvp_send_block(struct altera_cvp_conf *conf, const u32 *data, size_t len) { - u32 mask, words = len / sizeof(u32); + u32 words = len / sizeof(u32); int i, remainder; for (i = 0; i < words; i++) @@ -274,9 +275,10 @@ static int altera_cvp_send_block(struct /* write up to 3 trailing bytes, if any */ remainder = len % sizeof(u32); if (remainder) { - mask = BIT(remainder * 8) - 1; - if (mask) - conf->write_data(conf, *data & mask); + u32 word = 0; + + memcpy(&word, data, remainder); + conf->write_data(conf, word); } return 0;