mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-27 12:57:53 +00:00
io_uring/net: fix overflow check in io_recvmsg_mshot_prep()
[ Upstream commit8ede3db506
] The "controllen" variable is type size_t (unsigned long). Casting it to int could lead to an integer underflow. The check_add_overflow() function considers the type of the destination which is type int. If we add two positive values and the result cannot fit in an integer then that's counted as an overflow. However, if we cast "controllen" to an int and it turns negative, then negative values *can* fit into an int type so there is no overflow. Good: 100 + (unsigned long)-4 = 96 <-- overflow Bad: 100 + (int)-4 = 96 <-- no overflow I deleted the cast of the sizeof() as well. That's not a bug but the cast is unnecessary. Fixes:9b0fc3c054
("io_uring: fix types in io_recvmsg_multishot_overflow") Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Link: https://lore.kernel.org/r/138bd2e2-ede8-4bcc-aa7b-f3d9de167a37@moroto.mountain Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
parent
51d28472db
commit
59a534690e
1 changed files with 2 additions and 2 deletions
|
@ -544,10 +544,10 @@ static int io_recvmsg_mshot_prep(struct io_kiocb *req,
|
|||
|
||||
if (unlikely(namelen < 0))
|
||||
return -EOVERFLOW;
|
||||
if (check_add_overflow((int)sizeof(struct io_uring_recvmsg_out),
|
||||
if (check_add_overflow(sizeof(struct io_uring_recvmsg_out),
|
||||
namelen, &hdr))
|
||||
return -EOVERFLOW;
|
||||
if (check_add_overflow(hdr, (int)controllen, &hdr))
|
||||
if (check_add_overflow(hdr, controllen, &hdr))
|
||||
return -EOVERFLOW;
|
||||
|
||||
iomsg->namelen = namelen;
|
||||
|
|
Loading…
Reference in a new issue