Re: [PATCH v5.10-v5.15] Bluetooth: RFCOMM: Fix not validating setsockopt user input

[Greg KH <gregkh@linuxfoundation.org>]

On Mon, Jan 20, 2025 at 06:46:47AM +0000, Keerthana K wrote:
> From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
> 
> [ Upstream commit a97de7bff13b1cc825c1b1344eaed8d6c2d3e695 ]
> 
> syzbot reported rfcomm_sock_setsockopt_old() is copying data without
> checking user input length.
> 
> BUG: KASAN: slab-out-of-bounds in copy_from_sockptr_offset
> include/linux/sockptr.h:49 [inline]
> BUG: KASAN: slab-out-of-bounds in copy_from_sockptr
> include/linux/sockptr.h:55 [inline]
> BUG: KASAN: slab-out-of-bounds in rfcomm_sock_setsockopt_old
> net/bluetooth/rfcomm/sock.c:632 [inline]
> BUG: KASAN: slab-out-of-bounds in rfcomm_sock_setsockopt+0x893/0xa70
> net/bluetooth/rfcomm/sock.c:673
> Read of size 4 at addr ffff8880209a8bc3 by task syz-executor632/5064
> 
> Fixes: 9f2c8a03fbb3 ("Bluetooth: Replace RFCOMM link mode with security level")
> Fixes: bb23c0ab8246 ("Bluetooth: Add support for deferring RFCOMM connection setup")
> Reported-by: syzbot <syzkaller@googlegroups.com>
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> Signed-off-by: Keerthana K <keerthana.kalyanasundaram@broadcom.com>
> ---
>  net/bluetooth/rfcomm/sock.c | 14 +++++---------
>  1 file changed, 5 insertions(+), 9 deletions(-)

This breaks the build on 5.15.y systems, did you test it?

I'm dropping both patches now, please be more careful.

greg k-h