From: Pavel Begunkov Date: Tue, 26 Nov 2024 00:34:18 +0000 (+0000) Subject: io_uring: check for overflows in io_pin_pages X-Git-Tag: v6.11.11~124 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=29eac3eca72d4c2a71122050c37cd7d8f73ac4f3;p=thirdparty%2Fkernel%2Fstable.git io_uring: check for overflows in io_pin_pages 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: __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] ... 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 Link: https://lore.kernel.org/r/1b7520ddb168e1d537d64be47414a0629d0d8f8f.1732581026.git.asml.silence@gmail.com Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- diff --git a/io_uring/memmap.c b/io_uring/memmap.c index de5b584b7fab9..6d151e46f3d69 100644 --- a/io_uring/memmap.c +++ b/io_uring/memmap.c @@ -137,7 +137,12 @@ struct page **io_pin_pages(unsigned long uaddr, unsigned long len, int *npages) 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))