On 04/05/2020 23:00, Pavel Begunkov wrote:
> do_splice() doesn't expect len to be 0. Just always return 0 in this
> case as splice(2) do.
>
If it was missed, may you take a look? I reattached the patch btw killing
reported warnings.
---
From: Pavel Begunkov <asml.silence@xxxxxxxxx>
Subject: [PATCH] io_uring: fix zero len do_splice()
do_splice() doesn't expect len to be 0. Do the check in io_splice()
exactly as in sys_splice().
Fixes: 7d67af2c0134 ("io_uring: add splice(2) support")
Reported-by: Jann Horn <jannh@xxxxxxxxxx>
Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx>
---
fs/io_uring.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 65458eda2127..70d8943c337b 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2772,16 +2772,16 @@ static int io_splice(struct io_kiocb *req, bool
force_nonblock)
struct file *out = sp->file_out;
unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
loff_t *poff_in, *poff_out;
- long ret;
+ long ret = 0;
if (force_nonblock)
return -EAGAIN;
poff_in = (sp->off_in == -1) ? NULL : &sp->off_in;
poff_out = (sp->off_out == -1) ? NULL : &sp->off_out;
- ret = do_splice(in, poff_in, out, poff_out, sp->len, flags);
- if (force_nonblock && ret == -EAGAIN)
- return -EAGAIN;
+
+ if (sp->len)
+ ret = do_splice(in, poff_in, out, poff_out, sp->len, flags);
io_put_file(req, in, (sp->flags & SPLICE_F_FD_IN_FIXED));
req->flags &= ~REQ_F_NEED_CLEANUP;
--
2.24.0
