__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 --- io_uring/openclose.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
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;
base-commit: b927546677c876e26eba308550207c2ddf812a43
On 12/25/25 12:28 AM, Prithvi Tambewagh wrote:
__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
Thanks, just missing a:
Fixes: b9445598d8c6 ("io_uring: openat directly into fixed fd table")
which I'll add when applying.
On Thu, 25 Dec 2025 12:58:29 +0530, Prithvi Tambewagh wrote:
__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.
[...]
Applied, thanks!
[1/1] io_uring: fix filename leak in __io_openat_prep() commit: b14fad555302a2104948feaff70503b64c80ac01
Best regards,
On Thu, Dec 25, 2025 at 08:08:50AM -0700, Jens Axboe wrote:
On Thu, 25 Dec 2025 12:58:29 +0530, Prithvi Tambewagh wrote:
__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.
[...]
Applied, thanks!
[1/1] io_uring: fix filename leak in __io_openat_prep() commit: b14fad555302a2104948feaff70503b64c80ac01
Best regards,
Jens Axboe
Thank you!
Best Regards, Prithvi
linux-stable-mirror@lists.linaro.org
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Jens Axboe -
Prithvi -
Prithvi Tambewagh