From 34cae91215c6f65bed2a124fb9283da6ec0b8dd9 Mon Sep 17 00:00:00 2001 From: Caleb Sander Mateos Date: Wed, 12 Feb 2025 13:45:45 -0700 Subject: [PATCH] io_uring/uring_cmd: don't assume io_uring_cmd_data layout eaf72f7b414f ("io_uring/uring_cmd: cleanup struct io_uring_cmd_data layout") removed most of the places assuming struct io_uring_cmd_data has sqes as its first field. However, the EAGAIN case in io_uring_cmd() still compares ioucmd->sqe to the struct io_uring_cmd_data pointer using a void * cast. Since fa3595523d72 ("io_uring: get rid of alloc cache init_once handling"), sqes is no longer io_uring_cmd_data's first field. As a result, the pointers will always compare unequal and memcpy() may be called with the same source and destination. Replace the incorrect void * cast with the address of the sqes field. Signed-off-by: Caleb Sander Mateos Fixes: eaf72f7b414f ("io_uring/uring_cmd: cleanup struct io_uring_cmd_data layout") Link: https://lore.kernel.org/r/20250212204546.3751645-2-csander@purestorage.com Signed-off-by: Jens Axboe --- io_uring/uring_cmd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/io_uring/uring_cmd.c b/io_uring/uring_cmd.c index 1f6a82128b47..cfb22e1de0e7 100644 --- a/io_uring/uring_cmd.c +++ b/io_uring/uring_cmd.c @@ -252,7 +252,7 @@ int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags) if (ret == -EAGAIN) { struct io_uring_cmd_data *cache = req->async_data; - if (ioucmd->sqe != (void *) cache) + if (ioucmd->sqe != cache->sqes) memcpy(cache->sqes, ioucmd->sqe, uring_sqe_size(req->ctx)); return -EAGAIN; } else if (ret == -EIOCBQUEUED) { -- 2.25.1