[PATCH 1/2] io_uring/kbuf: fix signedness in this_len calculation

From: Qingyue Zhang
Date: Wed Aug 27 2025 - 07:46:57 EST


When importing and using buffers, buf->len is considered unsigned.
However, buf->len is converted to signed int when committing. This
can lead to unexpected behavior if buffer is large enough to be
interpreted as a negative value. Make min_t calculation unsigned.

Co-developed-by: Suoxing Zhang <aftern00n@xxxxxx>
Signed-off-by: Suoxing Zhang <aftern00n@xxxxxx>
Signed-off-by: Qingyue Zhang <chunzhennn@xxxxxx>
---
io_uring/kbuf.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/io_uring/kbuf.c b/io_uring/kbuf.c
index f2d2cc319faa..81a13338dfab 100644
--- a/io_uring/kbuf.c
+++ b/io_uring/kbuf.c
@@ -39,7 +39,7 @@ static bool io_kbuf_inc_commit(struct io_buffer_list *bl, int len)
u32 this_len;

buf = io_ring_head_to_buf(bl->buf_ring, bl->head, bl->mask);
- this_len = min_t(int, len, buf->len);
+ this_len = min_t(u32, len, buf->len);
buf->len -= this_len;
if (buf->len) {
buf->addr += this_len;
--
2.48.1