From: Pavel Begunkov <asml.silence@gmail.com>
Date: Tue, 7 Dec 2021 20:16:36 +0000
Subject: [PATCH] block: fix single bio async DIO error handling
Git-commit: 75feae73a28020e492fbad2323245455ef69d687
Patch-mainline: v5.16-rc5
References: jsc#PED-1183
BUG: KASAN: use-after-free in io_submit_one+0x496/0x2fe0 fs/aio.c:1882
CPU: 2 PID: 15100 Comm: syz-executor873 Not tainted 5.16.0-rc1-syzk #1
Hardware name: Red Hat KVM, BIOS 1.13.0-2.module+el8.3.0+7860+a7792d29
04/01/2014
Call Trace:
[...]
refcount_dec_and_test include/linux/refcount.h:333 [inline]
iocb_put fs/aio.c:1161 [inline]
io_submit_one+0x496/0x2fe0 fs/aio.c:1882
__do_sys_io_submit fs/aio.c:1938 [inline]
__se_sys_io_submit fs/aio.c:1908 [inline]
__x64_sys_io_submit+0x1c7/0x4a0 fs/aio.c:1908
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3a/0x80 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
__blkdev_direct_IO_async() returns errors from bio_iov_iter_get_pages()
directly, in which case upper layers won't be expecting ->ki_complete
to be called by the block layer and will terminate the request. However,
there is also bio_endio() leading to a second ->ki_complete and a double
free.
Fixes: 54a88eb838d37 ("block: add single bio async direct IO helper")
Reported-by: George Kennedy <george.kennedy@oracle.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/c9eb786f6cef041e159e6287de131bec0719ad5c.1638907997.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Hannes Reinecke <hare@suse.com>
---
block/fops.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/block/fops.c b/block/fops.c
index ad732a36f9b3..8d329ca56b0f 100644
--- a/block/fops.c
+++ b/block/fops.c
@@ -340,8 +340,7 @@ static ssize_t __blkdev_direct_IO_async(struct kiocb *iocb,
} else {
ret = bio_iov_iter_get_pages(bio, iter);
if (unlikely(ret)) {
- bio->bi_status = BLK_STS_IOERR;
- bio_endio(bio);
+ bio_put(bio);
return ret;
}
}
--
2.35.3