6.11-stable review patch. If anyone has any objections, please let me know.
------------------
From: Pavel Begunkov asml.silence@gmail.com
commit 0c0a4eae26ac78379d0c1db053de168a8febc6c9 upstream.
WARNING: CPU: 0 PID: 5834 at io_uring/memmap.c:144 io_pin_pages+0x149/0x180 io_uring/memmap.c:144 CPU: 0 UID: 0 PID: 5834 Comm: syz-executor825 Not tainted 6.12.0-next-20241118-syzkaller #0 Call Trace: <TASK> __io_uaddr_map+0xfb/0x2d0 io_uring/memmap.c:183 io_rings_map io_uring/io_uring.c:2611 [inline] io_allocate_scq_urings+0x1c0/0x650 io_uring/io_uring.c:3470 io_uring_create+0x5b5/0xc00 io_uring/io_uring.c:3692 io_uring_setup io_uring/io_uring.c:3781 [inline] ... </TASK>
io_pin_pages()'s uaddr parameter came directly from the user and can be garbage. Don't just add size to it as it can overflow.
Cc: stable@vger.kernel.org Reported-by: syzbot+2159cbb522b02847c053@syzkaller.appspotmail.com Signed-off-by: Pavel Begunkov asml.silence@gmail.com Link: https://lore.kernel.org/r/1b7520ddb168e1d537d64be47414a0629d0d8f8f.173258102... Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- io_uring/memmap.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
--- a/io_uring/memmap.c +++ b/io_uring/memmap.c @@ -137,7 +137,12 @@ struct page **io_pin_pages(unsigned long struct page **pages; int ret;
- end = (uaddr + len + PAGE_SIZE - 1) >> PAGE_SHIFT; + if (check_add_overflow(uaddr, len, &end)) + return ERR_PTR(-EOVERFLOW); + if (check_add_overflow(end, PAGE_SIZE - 1, &end)) + return ERR_PTR(-EOVERFLOW); + + end = end >> PAGE_SHIFT; start = uaddr >> PAGE_SHIFT; nr_pages = end - start; if (WARN_ON_ONCE(!nr_pages))