diff options
| author | Jens Axboe <axboe@kernel.dk> | 2026-03-19 14:29:09 -0600 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-03-25 11:13:19 +0100 |
| commit | c9105481bd403aaa951e332e828da99aa013f402 (patch) | |
| tree | 88a9b5980529aac15568992cc17f048be8527a37 /io_uring | |
| parent | bf33554b6abf7e7faeadd8af1b82037ea755a6bb (diff) | |
io_uring/kbuf: fix missing BUF_MORE for incremental buffers at EOF
commit 3ecd3e03144b38a21a3b70254f1b9d2e16629b09 upstream.
For a zero length transfer, io_kbuf_inc_commit() is called with !len.
Since we never enter the while loop to consume the buffers,
io_kbuf_inc_commit() ends up returning true, consuming the buffer. But
if no data was consumed, by definition it cannot have consumed the
buffer. Return false for that case.
Reported-by: Martin Michaelis <code@mgjm.de>
Cc: stable@vger.kernel.org
Fixes: ae98dbf43d75 ("io_uring/kbuf: add support for incremental buffer consumption")
Link: https://github.com/axboe/liburing/issues/1553
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'io_uring')
| -rw-r--r-- | io_uring/kbuf.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/io_uring/kbuf.c b/io_uring/kbuf.c index e7f444953dfb..a4cb6752b7aa 100644 --- a/io_uring/kbuf.c +++ b/io_uring/kbuf.c @@ -34,6 +34,10 @@ struct io_provide_buf { static bool io_kbuf_inc_commit(struct io_buffer_list *bl, int len) { + /* No data consumed, return false early to avoid consuming the buffer */ + if (!len) + return false; + while (len) { struct io_uring_buf *buf; u32 buf_len, this_len; |