From: Pali Rohár <pali@xxxxxxxxxx> [ Upstream commit 8ebe2607965d3e2dc02029e8c7dd35fbe508ffd0 ] Before parsing CISTPL_VERS_1 structure check that its size is at least two bytes to prevent buffer overflow. Signed-off-by: Pali Rohár <pali@xxxxxxxxxx> Link: https://lore.kernel.org/r/20200727133837.19086-2-pali@xxxxxxxxxx Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/mmc/core/sdio_cis.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/mmc/core/sdio_cis.c b/drivers/mmc/core/sdio_cis.c index e0655278c5c32..3efaa9534a777 100644 --- a/drivers/mmc/core/sdio_cis.c +++ b/drivers/mmc/core/sdio_cis.c @@ -26,6 +26,9 @@ static int cistpl_vers_1(struct mmc_card *card, struct sdio_func *func, unsigned i, nr_strings; char **buffer, *string; + if (size < 2) + return 0; + /* Find all null-terminated (including zero length) strings in the TPLLV1_INFO field. Trailing garbage is ignored. */ buf += 2; -- 2.25.1
