fs/aio: Restrict kiocb_set_cancel_fn() to I/O submitted via libaio

commit b820de7 upstream. If kiocb_set_cancel_fn() is called for I/O submitted via io_uring, the following kernel warning appears: WARNING: CPU: 3 PID: 368 at fs/aio.c:598 kiocb_set_cancel_fn+0x9c/0xa8 Call trace: kiocb_set_cancel_fn+0x9c/0xa8 ffs_epfile_read_iter+0x144/0x1d0 io_read+0x19c/0x498 io_issue_sqe+0x118/0x27c io_submit_sqes+0x25c/0x5fc __arm64_sys_io_uring_enter+0x104/0xab0 invoke_syscall+0x58/0x11c el0_svc_common+0xb4/0xf4 do_el0_svc+0x2c/0xb0 el0_svc+0x2c/0xa4 el0t_64_sync_handler+0x68/0xb4 el0t_64_sync+0x1a4/0x1a8 Fix this by setting the IOCB_AIO_RW flag for read and write I/O that is submitted by libaio. Suggested-by: Jens Axboe <[email protected]> Cc: Christoph Hellwig <[email protected]> Cc: Avi Kivity <[email protected]> Cc: Sandeep Dhavale <[email protected]> Cc: Jens Axboe <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Kent Overstreet <[email protected]> Cc: [email protected] Signed-off-by: Bart Van Assche <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Christian Brauner <[email protected]> Signed-off-by: Bart Van Assche <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
anthraxx · Mar 1, 2024 · ea1cd64 · ea1cd64
1 parent bff0a06
commit ea1cd64
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Showing 2 changed files with 10 additions and 1 deletion.
diff --git a/fs/aio.c b/fs/aio.c
@@ -569,6 +569,13 @@ void kiocb_set_cancel_fn(struct kiocb *iocb, kiocb_cancel_fn *cancel)
 	struct kioctx *ctx = req->ki_ctx;
 	unsigned long flags;
 
+	/*
+	 * kiocb didn't come from aio or is neither a read nor a write, hence
+	 * ignore it.
+	 */
+	if (!(iocb->ki_flags & IOCB_AIO_RW))
+		return;
+
 	if (WARN_ON_ONCE(!list_empty(&req->ki_list)))
 		return;
 
@@ -1454,7 +1461,7 @@ static int aio_prep_rw(struct kiocb *req, const struct iocb *iocb)
 	req->ki_complete = aio_complete_rw;
 	req->private = NULL;
 	req->ki_pos = iocb->aio_offset;
-	req->ki_flags = iocb_flags(req->ki_filp);
+	req->ki_flags = iocb_flags(req->ki_filp) | IOCB_AIO_RW;
 	if (iocb->aio_flags & IOCB_FLAG_RESFD)
 		req->ki_flags |= IOCB_EVENTFD;
 	req->ki_hint = ki_hint_validate(file_write_hint(req->ki_filp));

diff --git a/include/linux/fs.h b/include/linux/fs.h
@@ -316,6 +316,8 @@ enum rw_hint {
 /* iocb->ki_waitq is valid */
 #define IOCB_WAITQ		(1 << 19)
 #define IOCB_NOIO		(1 << 20)
+/* kiocb is a read or write operation submitted by fs/aio.c. */
+#define IOCB_AIO_RW		(1 << 23)
 
 struct kiocb {
 	struct file		*ki_filp;