Re: Patch "btrfs: properly limit inline data extent according to block size" has been added to the 6.12-stable tree

在 2025/5/23 07:31, Sasha Levin 写道:

This is a note to let you know that I've just added the patch titled

 btrfs: properly limit inline data extent according to block size

to the 6.12-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: btrfs-properly-limit-inline-data-extent-according-to.patch and it can be found in the queue-6.12 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

Please drop this patch from all stable trees.

This is only for a debug feature, 2K block size, and it will never be exposed to end users (only to allow people without a 64K page sized system to test subpage routine on x86_64).

Thanks, Qu

commit a5afc96d757771c992eb3af4629a562ec52ba1dc Author: Qu Wenruo wqu@suse.com Date: Tue Feb 25 14:30:44 2025 +1030

 btrfs: properly limit inline data extent according to block size
 
 [ Upstream commit 23019d3e6617a8ec99a8d2f5947aa3dd8a74a1b8 ]
 
 Btrfs utilizes inline data extent for the following cases:
 
 - Regular small files
 - Symlinks
 
 And "btrfs check" detects any file extents that are too large as an
 error.
 
 It's not a problem for 4K block size, but for the incoming smaller
 block sizes (2K), it can cause problems due to bad limits:
 
 - Non-compressed inline data extents
   We do not allow a non-compressed inline data extent to be as large as
   block size.
 
 - Symlinks
   Currently the only real limit on symlinks are 4K, which can be larger
   than 2K block size.
 
 These will result btrfs-check to report too large file extents.
 
 Fix it by adding proper size checks for the above cases.
 
 Signed-off-by: Qu Wenruo <wqu@suse.com>
 Reviewed-by: David Sterba <dsterba@suse.com>
 Signed-off-by: David Sterba <dsterba@suse.com>
 Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 9ce1270addb04..0da2611fb9c85 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -623,6 +623,10 @@ static bool can_cow_file_range_inline(struct btrfs_inode *inode, if (size > fs_info->sectorsize) return false;

• /* We do not allow a non-compressed extent to be as large as block size. */
• if (data_len >= fs_info->sectorsize)

• return false;
  

• /* We cannot exceed the maximum inline data size. */ if (data_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info)) return false;

@@ -8691,7 +8695,12 @@ static int btrfs_symlink(struct mnt_idmap *idmap, struct inode *dir, struct extent_buffer *leaf; name_len = strlen(symname);

• if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info))

• /*

• * Symlinks utilize uncompressed inline extent data, which should not
  

• * reach block size.
  

• */
  

• if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info) ||

•    name_len >= fs_info->sectorsize)
  

  return -ENAMETOOLONG;

inode = new_inode(dir->i_sb);