FAILED: patch "[PATCH] xfs: fix buffer overruns in xfs_ioc_attr_list" failed to apply to 6.6-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 6.6-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-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 0b9081a774ee7b9dff1e9ac3765b73c1d6bba5b2
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026110440-penalize-refocus-9272@gregkh' --subject-prefix 'PATCH 6.6.y' 'HEAD^..'

Possible dependencies:



thanks,

greg k-h

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

From 0b9081a774ee7b9dff1e9ac3765b73c1d6bba5b2 Mon Sep 17 00:00:00 2001
From: "Darrick J. Wong" <djwong@kernel.org>
Date: Tue, 22 Sep 2026 22:58:08 -0700
Subject: [PATCH] xfs: fix buffer overruns in xfs_ioc_attr_list

When we converted the al_offset array in struct xfs_attrlist into a VLA,
the size of the object shrank by 4 bytes.  Unfortunately, the buffer
size validation in the attrlist ioctl wasn't updated to notice this, so
the al_offset[0] assignment blindly writes off the end of the buffer.
LOLLM noticed the omitted check and complained.

Cc: stable@vger.kernel.org # v6.5
Fixes: 371baf5c9750a2 ("xfs: convert flex-array declarations in struct xfs_attrlist*")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>

diff --git a/fs/xfs/xfs_handle.c b/fs/xfs/xfs_handle.c
index 0689cade8f74..fd9d4d8258ff 100644
--- a/fs/xfs/xfs_handle.c
+++ b/fs/xfs/xfs_handle.c
@@ -409,7 +409,7 @@ xfs_ioc_attr_list(
 	void				*buffer;
 	int				error;
 
-	if (bufsize < sizeof(struct xfs_attrlist) ||
+	if (bufsize < struct_size(alist, al_offset, 1) ||
 	    bufsize > XFS_XATTR_LIST_MAX)
 		return -EINVAL;