FAILED: patch "[PATCH] btrfs: tree-checker: fix the incorrect inode ref size check" failed to apply to 5.4-stable tree

The patch below does not apply to the 5.4-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 <[email protected]>.

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-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x 96fa515e70f3e4b98685ef8cac9d737fc62f10e1
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2025092135-breeding-chrome-585a@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

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

From 96fa515e70f3e4b98685ef8cac9d737fc62f10e1 Mon Sep 17 00:00:00 2001
From: Qu Wenruo <[email protected]>
Date: Tue, 16 Sep 2025 07:54:06 +0930
Subject: [PATCH] btrfs: tree-checker: fix the incorrect inode ref size check

[BUG]
Inside check_inode_ref(), we need to make sure every structure, including the btrfs_inode_extref header, is covered by the item. But our code is incorrectly using "sizeof(iref)", where @iref is just a pointer.

This means "sizeof(iref)" will always be "sizeof(void *)", which is much smaller than "sizeof(struct btrfs_inode_extref)".

This will allow some bad inode extrefs to sneak in, defeating tree-checker.

[FIX]
Fix the typo by calling "sizeof(*iref)", which is the same as "sizeof(struct btrfs_inode_extref)", and will be the correct behavior we want.

index 0f556f4de3f9..a997c7cc35a2 100644
@@ -1756,10 +1756,10 @@ static int check_inode_ref(struct extent_buffer *leaf,
 	while (ptr < end) {
 		u16 namelen;
 
-		if (unlikely(ptr + sizeof(iref) > end)) {
+		if (unlikely(ptr + sizeof(*iref) > end)) {
 			inode_ref_err(leaf, slot,
 			"inode ref overflow, ptr %lu end %lu inode_ref_size %zu",
-				ptr, end, sizeof(iref));
+				ptr, end, sizeof(*iref));
 			return -EUCLEAN;
 		}