6.6-stable review patch. If anyone has any objections, please let me know.
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From: Jens Axboe axboe@kernel.dk
[ Upstream commit 9865346b7e8374b57f1c3ccacdc77846c6352ff4 ]
Move the buffer list 'is_ready' check below the validity check for the buffer list for a given group.
Fixes: 5cf4f52e6d8a ("io_uring: free io_buffer_list entries via RCU") Reported-by: Dan Carpenter dan.carpenter@linaro.org Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- io_uring/kbuf.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/io_uring/kbuf.c b/io_uring/kbuf.c index 12eec4778c5b1..e8516f3bbbaaa 100644 --- a/io_uring/kbuf.c +++ b/io_uring/kbuf.c @@ -743,6 +743,8 @@ void *io_pbuf_get_address(struct io_ring_ctx *ctx, unsigned long bgid)
bl = __io_buffer_get_list(ctx, smp_load_acquire(&ctx->io_bl), bgid);
+ if (!bl || !bl->is_mmap) + return NULL; /* * Ensure the list is fully setup. Only strictly needed for RCU lookup * via mmap, and in that case only for the array indexed groups. For @@ -750,8 +752,6 @@ void *io_pbuf_get_address(struct io_ring_ctx *ctx, unsigned long bgid) */ if (!smp_load_acquire(&bl->is_ready)) return NULL; - if (!bl || !bl->is_mmap) - return NULL;
return bl->buf_ring; }