Jens Axboe 8b51a3956d io_uring: fix crash with IORING_SETUP_NO_MMAP and invalid SQ ring address ... If we specify a valid CQ ring address but an invalid SQ ring address, we'll correctly spot this and free the allocated pages and clear them to NULL. However, we don't clear the ring page count, and hence will attempt to free the pages again. We've already cleared the address of the page array when freeing them, but we don't check for that. This causes the following crash: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 Oops [#1] Modules linked in: CPU: 0 PID: 20 Comm: kworker/u2:1 Not tainted 6.6.0-rc5-dirty #56 Hardware name: ucbbar,riscvemu-bare (DT) Workqueue: events_unbound io_ring_exit_work epc : io_pages_free+0x2a/0x58 ra : io_rings_free+0x3a/0x50 epc : ffffffff808811a2 ra : ffffffff80881406 sp : ffff8f80000c3cd0 status: 0000000200000121 badaddr: 0000000000000000 cause: 000000000000000d [<ffffffff808811a2>] io_pages_free+0x2a/0x58 [<ffffffff80881406>] io_rings_free+0x3a/0x50 [<ffffffff80882176>] io_ring_exit_work+0x37e/0x424 [<ffffffff80027234>] process_one_work+0x10c/0x1f4 [<ffffffff8002756e>] worker_thread+0x252/0x31c [<ffffffff8002f5e4>] kthread+0xc4/0xe0 [<ffffffff8000332a>] ret_from_fork+0xa/0x1c Check for a NULL array in io_pages_free(), but also clear the page counts when we free them to be on the safer side. Reported-by: rtm@csail.mit.edu Fixes: 03d89a2de2 ("io_uring: support for user allocated memory for rings/sqes") Cc: stable@vger.kernel.org Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>		2023-10-18 09:22:14 -06:00
..
advise.c
advise.h
alloc_cache.h
cancel.c
cancel.h
epoll.c
epoll.h
fdinfo.c	io_uring/fdinfo: only print ->sq_array[] if it's there	2023-09-01 15:08:29 -06:00
fdinfo.h
filetable.c
filetable.h
fs.c	io_uring/fs: remove sqe->rw_flags checking from LINKAT	2023-09-29 03:07:09 -06:00
fs.h
io-wq.c	io-wq: fully initialize wqe before calling cpuhp_state_add_instance_nocalls()	2023-10-05 14:11:18 -06:00
io-wq.h	io_uring: break out of iowq iopoll on teardown	2023-09-07 09:02:27 -06:00
io_uring.c	io_uring: fix crash with IORING_SETUP_NO_MMAP and invalid SQ ring address	2023-10-18 09:22:14 -06:00
io_uring.h	io_uring: ensure io_lockdep_assert_cq_locked() handles disabled rings	2023-10-03 08:12:54 -06:00
kbuf.c	io_uring/kbuf: don't allow registered buffer rings on highmem pages	2023-10-03 08:12:28 -06:00
kbuf.h
Makefile
msg_ring.c
msg_ring.h
net.c	io_uring/net: fix iter retargeting for selected buf	2023-09-14 10:12:55 -06:00
net.h
nop.c
nop.h
notif.c
notif.h
opdef.c
opdef.h
openclose.c
openclose.h
poll.c
poll.h
refs.h
rsrc.c
rsrc.h
rw.c
rw.h
slist.h
splice.c
splice.h
sqpoll.c
sqpoll.h
statx.c
statx.h
sync.c
sync.h
tctx.c
tctx.h
timeout.c
timeout.h
uring_cmd.c
uring_cmd.h
xattr.c
xattr.h