On Thu, 16 Sep 2021 17:33:43 +0800, Yu Kuai wrote:

This patch set tries to fix that client might oops if nbd server send
unexpected message to client, for example, our syzkaller report a uaf
in nbd_read_stat():

Call trace:
 dump_backtrace+0x0/0x310 arch/arm64/kernel/time.c:78
 show_stack+0x28/0x38 arch/arm64/kernel/traps.c:158
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x144/0x1b4 lib/dump_stack.c:118
 print_address_description+0x68/0x2d0 mm/kasan/report.c:253
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report+0x134/0x2f0 mm/kasan/report.c:409
 check_memory_region_inline mm/kasan/kasan.c:260 [inline]
 __asan_load4+0x88/0xb0 mm/kasan/kasan.c:699
 __read_once_size include/linux/compiler.h:193 [inline]
 blk_mq_rq_state block/blk-mq.h:106 [inline]
 blk_mq_request_started+0x24/0x40 block/blk-mq.c:644
 nbd_read_stat drivers/block/nbd.c:670 [inline]
 recv_work+0x1bc/0x890 drivers/block/nbd.c:749
 process_one_work+0x3ec/0x9e0 kernel/workqueue.c:2147
 worker_thread+0x80/0x9d0 kernel/workqueue.c:2302
 kthread+0x1d8/0x1e0 kernel/kthread.c:255
 ret_from_fork+0x10/0x18 arch/arm64/kernel/entry.S:1174

[...]

Applied, thanks!

[1/7] nbd: don't handle response without a corresponding request message
      commit: b5644a3a79bf3be5f1238db1b2f241374b27b0f0
[2/7] nbd: make sure request completion won't concurrent
      commit: d14b304f558f8c8f53da3a8d0c0b671f14a9c2f4
[3/7] nbd: check sock index in nbd_read_stat()
      commit: dbd73178da676945d8bbcf6afe731623f683ce0a
[4/7] nbd: don't start request if nbd_queue_rq() failed
      commit: a83fdc85365586dc5c0f3ff91680e18e37a66f19
[5/7] nbd: clean up return value checking of sock_xmit()
      commit: 6157a8f489909db00151a4e361903b9099b03b75
[6/7] nbd: partition nbd_read_stat() into nbd_read_reply() and nbd_handle_reply()
      commit: 961e9f50be9bb47835b0ac7e08d55d2d0a45e493
[7/7] nbd: fix uaf in nbd_handle_reply()
      commit: 52c90e0184f67eecb00b53b79bfdf75e0274f8fd

Best regards,
-- 
Jens Axboe