On Sat, Nov 20, 2021 at 06:02:02PM +0300, Pavel Skripkin wrote: > On 11/19/21 12:27, syzbot wrote: > > Hello, > > > > syzbot found the following issue on: > > > > HEAD commit: 8d0112ac6fd0 Merge tag 'net-5.16-rc2' of git://git.kernel... > > git tree: net > > console output: https://syzkaller.appspot.com/x/log.txt?x=14e3eeaab00000 > > kernel config: https://syzkaller.appspot.com/x/.config?x=6d3b8fd1977c1e73 > > dashboard link: https://syzkaller.appspot.com/bug?extid=aab53008a5adf26abe91 > > compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 > > > > Unfortunately, I don't have any reproducer for this issue yet. > > > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > > Reported-by: syzbot+aab53008a5adf26abe91@xxxxxxxxxxxxxxxxxxxxxxxxx > > > > Free swap = 0kB > > Total swap = 0kB > > 2097051 pages RAM > > 0 pages HighMem/MovableOnly > > 384517 pages reserved > > 0 pages cma reserved > > ================================================================== > > BUG: KASAN: use-after-free in rxe_queue_cleanup+0xf4/0x100 drivers/infiniband/sw/rxe/rxe_queue.c:193 > > Read of size 8 at addr ffff88814a6b6e90 by task syz-executor.3/9534 > > > > On error handling path in rxe_qp_from_init() qp->sq.queue is freed and then > rxe_create_qp() will drop last reference to this object. qp clean up > function will try to free this queue one time and it causes UAF bug. > > Just for thoughts. You are right, can you please submit patch? Thanks > > > diff --git a/drivers/infiniband/sw/rxe/rxe_qp.c > b/drivers/infiniband/sw/rxe/rxe_qp.c > index 975321812c87..54b8711321c1 100644 > --- a/drivers/infiniband/sw/rxe/rxe_qp.c > +++ b/drivers/infiniband/sw/rxe/rxe_qp.c > @@ -359,6 +359,7 @@ int rxe_qp_from_init(struct rxe_dev *rxe, struct rxe_qp > *qp, struct rxe_pd *pd, > > err2: > rxe_queue_cleanup(qp->sq.queue); > + qp->sq.queue = NULL; > err1: > qp->pd = NULL; > qp->rcq = NULL; > > > > > > With regards, > Pavel Skripkin
