From: Al Viro <[email protected]> This patch has been added to the 3.18 stable tree. If you have any objections, please let us know.
=============== [ Upstream commit 451a2886b6bf90e2fb378f7c46c655450fb96e81 ] unfortunately, allowing an arbitrary 16bit value means a possibility of overflow in the calculation of total number of pages in bio_map_user_iov() - we rely on there being no more than PAGE_SIZE members of sum in the first loop there. If that sum wraps around, we end up allocating too small array of pointers to pages and it's easy to overflow it in the second loop. X-Coverup: TINC (and there's no lumber cartel either) Cc: [email protected] # way, way back Signed-off-by: Al Viro <[email protected]> Signed-off-by: Sasha Levin <[email protected]> --- drivers/scsi/sg.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index 07b2ea1..b3c8aab 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -1785,6 +1785,9 @@ sg_start_req(Sg_request *srp, unsigned char *cmd) md->from_user = 0; } + if (unlikely(iov_count > UIO_MAXIOV)) + return -EINVAL; + if (iov_count) { int len, size = sizeof(struct sg_iovec) * iov_count; struct iovec *iov; -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
