From 8e587ab43cb92a9e57f99ea8d6c069ee65863707 Mon Sep 17 00:00:00 2001 From: Sidong Yang Date: Wed, 19 Mar 2025 11:24:01 +0000 Subject: [PATCH] btrfs: ioctl: don't free iov when btrfs_encoded_read() returns -EAGAIN Fix a bug in encoded read that mistakenly frees the iov in case btrfs_encoded_read() returns -EAGAIN assuming the structure will be reused. This can happen when when receiving requests concurrently, the io_uring subsystem does not reset the data, and the last free will happen in btrfs_uring_read_finished(). Handle the -EAGAIN error and skip freeing iov. CC: stable@vger.kernel.org # 6.13+ Signed-off-by: Sidong Yang Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/ioctl.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index a13d81bb56a0..63aeacc54945 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -4902,6 +4902,8 @@ static int btrfs_uring_encoded_read(struct io_uring_cmd *cmd, unsigned int issue ret = btrfs_encoded_read(&kiocb, &data->iter, &data->args, &cached_state, &disk_bytenr, &disk_io_size); + if (ret == -EAGAIN) + goto out_acct; if (ret < 0 && ret != -EIOCBQUEUED) goto out_free;