FAILED: patch "[PATCH] btrfs: fix double inode unlock for direct IO sync writes" failed to apply to 6.10-stable tree

FAILED: patch "[PATCH] btrfs: fix double inode unlock for direct IO sync writes" failed to apply to 6.10-stable tree

[gregkh]

The patch below does not apply to the 6.10-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-6.10.y
git checkout FETCH_HEAD
git cherry-pick -x e0391e92f9ab4fb3dbdeb139c967dcfa7ac4b115
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2024081250-taco-simmering-1043@gregkh' --subject-prefix 'PATCH 6.10.y' HEAD^..

Possible dependencies:

e0391e92f9ab ("btrfs: fix double inode unlock for direct IO sync writes")
56b7169f691c ("btrfs: use a btrfs_inode local variable at btrfs_sync_file()")
e641e323abb3 ("btrfs: pass a btrfs_inode to btrfs_wait_ordered_range()")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From e0391e92f9ab4fb3dbdeb139c967dcfa7ac4b115 Mon Sep 17 00:00:00 2001
From: Filipe Manana <fdmanana@suse.com>
Date: Fri, 2 Aug 2024 09:38:51 +0100
Subject: [PATCH] btrfs: fix double inode unlock for direct IO sync writes

If we do a direct IO sync write, at btrfs_sync_file(), and we need to skip
inode logging or we get an error starting a transaction or an error when
flushing delalloc, we end up unlocking the inode when we shouldn't under
the 'out_release_extents' label, and then unlock it again at
btrfs_direct_write().

Fix that by checking if we have to skip inode unlocking under that label.

Reported-by: syzbot+7dbbb74af6291b5a5a8b@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/000000000000dfd631061eaeb4bc@google.com/
Fixes: 939b656bc8ab ("btrfs: fix corruption after buffer fault in during direct IO append write")
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 9f10a9f23fcc..9914419f3b7d 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -1868,7 +1868,10 @@ int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
 
 out_release_extents:
 	btrfs_release_log_ctx_extents(&ctx);
-	btrfs_inode_unlock(inode, BTRFS_ILOCK_MMAP);
+	if (skip_ilock)
+		up_write(&inode->i_mmap_lock);
+	else
+		btrfs_inode_unlock(inode, BTRFS_ILOCK_MMAP);
 	goto out;
 }
 

Re: FAILED: patch "[PATCH] btrfs: fix double inode unlock for direct IO sync writes" failed to apply to 6.10-stable tree

[Filipe Manana]

On Mon, Aug 12, 2024 at 4:07 PM <gregkh@linuxfoundation.org> wrote:
>
>
> The patch below does not apply to the 6.10-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-6.10.y
> git checkout FETCH_HEAD
> git cherry-pick -x e0391e92f9ab4fb3dbdeb139c967dcfa7ac4b115
> # <resolve conflicts, build, test, etc.>
> git commit -s
> git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2024081250-taco-simmering-1043@gregkh' --subject-prefix 'PATCH 6.10.y' HEAD^..
>
> Possible dependencies:
>
> e0391e92f9ab ("btrfs: fix double inode unlock for direct IO sync writes")
> 56b7169f691c ("btrfs: use a btrfs_inode local variable at btrfs_sync_file()")
> e641e323abb3 ("btrfs: pass a btrfs_inode to btrfs_wait_ordered_range()")

I have a version of the fix ready and tested for each stable branch,
I'll send them out soon with you and stable@ in cc.

Thanks.

>
> thanks,
>
> greg k-h
>
> ------------------ original commit in Linus's tree ------------------
>
> From e0391e92f9ab4fb3dbdeb139c967dcfa7ac4b115 Mon Sep 17 00:00:00 2001
> From: Filipe Manana <fdmanana@suse.com>
> Date: Fri, 2 Aug 2024 09:38:51 +0100
> Subject: [PATCH] btrfs: fix double inode unlock for direct IO sync writes
>
> If we do a direct IO sync write, at btrfs_sync_file(), and we need to skip
> inode logging or we get an error starting a transaction or an error when
> flushing delalloc, we end up unlocking the inode when we shouldn't under
> the 'out_release_extents' label, and then unlock it again at
> btrfs_direct_write().
>
> Fix that by checking if we have to skip inode unlocking under that label.
>
> Reported-by: syzbot+7dbbb74af6291b5a5a8b@syzkaller.appspotmail.com
> Link: https://lore.kernel.org/linux-btrfs/000000000000dfd631061eaeb4bc@google.com/
> Fixes: 939b656bc8ab ("btrfs: fix corruption after buffer fault in during direct IO append write")
> Reviewed-by: Josef Bacik <josef@toxicpanda.com>
> Signed-off-by: Filipe Manana <fdmanana@suse.com>
> Signed-off-by: David Sterba <dsterba@suse.com>
>
> diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
> index 9f10a9f23fcc..9914419f3b7d 100644
> --- a/fs/btrfs/file.c
> +++ b/fs/btrfs/file.c
> @@ -1868,7 +1868,10 @@ int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
>
>  out_release_extents:
>         btrfs_release_log_ctx_extents(&ctx);
> -       btrfs_inode_unlock(inode, BTRFS_ILOCK_MMAP);
> +       if (skip_ilock)
> +               up_write(&inode->i_mmap_lock);
> +       else
> +               btrfs_inode_unlock(inode, BTRFS_ILOCK_MMAP);
>         goto out;
>  }
>
>