The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x b14fad555302a2104948feaff70503b64c80ac01 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2025122931-palm-unfixed-3968@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From b14fad555302a2104948feaff70503b64c80ac01 Mon Sep 17 00:00:00 2001 From: Prithvi Tambewagh activprithvi@gmail.com Date: Thu, 25 Dec 2025 12:58:29 +0530 Subject: [PATCH] io_uring: fix filename leak in __io_openat_prep()
__io_openat_prep() allocates a struct filename using getname(). However, for the condition of the file being installed in the fixed file table as well as having O_CLOEXEC flag set, the function returns early. At that point, the request doesn't have REQ_F_NEED_CLEANUP flag set. Due to this, the memory for the newly allocated struct filename is not cleaned up, causing a memory leak.
Fix this by setting the REQ_F_NEED_CLEANUP for the request just after the successful getname() call, so that when the request is torn down, the filename will be cleaned up, along with other resources needing cleanup.
Reported-by: syzbot+00e61c43eb5e4740438f@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=00e61c43eb5e4740438f Tested-by: syzbot+00e61c43eb5e4740438f@syzkaller.appspotmail.com Cc: stable@vger.kernel.org Signed-off-by: Prithvi Tambewagh activprithvi@gmail.com Fixes: b9445598d8c6 ("io_uring: openat directly into fixed fd table") Signed-off-by: Jens Axboe axboe@kernel.dk
diff --git a/io_uring/openclose.c b/io_uring/openclose.c index bfeb91b31bba..15dde9bd6ff6 100644 --- a/io_uring/openclose.c +++ b/io_uring/openclose.c @@ -73,13 +73,13 @@ static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe open->filename = NULL; return ret; } + req->flags |= REQ_F_NEED_CLEANUP;
open->file_slot = READ_ONCE(sqe->file_index); if (open->file_slot && (open->how.flags & O_CLOEXEC)) return -EINVAL;
open->nofile = rlimit(RLIMIT_NOFILE); - req->flags |= REQ_F_NEED_CLEANUP; if (io_openat_force_async(open)) req->flags |= REQ_F_FORCE_ASYNC; return 0;