FAILED: patch "[PATCH] ntfs: fix memmove overlap in ntfs_new_attr_flags" failed to apply to 7.2-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 7.2-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-7.2.y
git checkout FETCH_HEAD
git cherry-pick -x acb1095fd2db884b417cb70808c886e4b615ff05
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026102234-sector-enjoyably-8d59@gregkh' --subject-prefix 'PATCH 7.2.y' 'HEAD^..'

Possible dependencies:



thanks,

greg k-h

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

From acb1095fd2db884b417cb70808c886e4b615ff05 Mon Sep 17 00:00:00 2001
From: Hongling Zeng <zenghongling@kylinos.cn>
Date: Mon, 24 Aug 2026 15:59:35 +0800
Subject: [PATCH] ntfs: fix memmove overlap in ntfs_new_attr_flags

When the record shrinks while the payload offsets increase (e.g., enabling
compression reduces padding, making arec_size < old_arec_size, but the header
grows by 8 bytes), moving the name first can overwrite the old mapping_pairs
before they are copied. Move mapping_pairs first in this case.

Since mp_ofs is derived from name_ofs, they always change in the same
direction. Checking name_ofs alone is sufficient.

Fixes: fc053f05ca28 ("ntfs: add reparse and ea operations")
Cc: stable@vger.kernel.org
Signed-off-by: Hongling Zeng <zenghongling@kylinos.cn>
Reviewed-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>

diff --git a/fs/ntfs/ea.c b/fs/ntfs/ea.c
index 9f0222c172d9..0bc29bf1f050 100644
--- a/fs/ntfs/ea.c
+++ b/fs/ntfs/ea.c
@@ -753,15 +753,36 @@ static int ntfs_new_attr_flags(struct ntfs_inode *ni, __le32 fattr)
 	old_arec_size = le32_to_cpu(a->length);
 
 	/*
-	 * Move payloads before shrinking the record.  Otherwise resizing moves
+	 * Move payloads before shrinking the record. Otherwise resizing moves
 	 * the following attribute over the old payload before it can be copied.
+	 *
+	 * When offsets increase, move mapping_pairs first to avoid name
+	 * overwriting the start of mapping_pairs.
 	 */
 	if (arec_size < old_arec_size) {
-		if (a->name_length && name_ofs != old_name_ofs)
-			memmove((u8 *)a + name_ofs, (u8 *)a + old_name_ofs,
-				a->name_length * sizeof(__le16));
-		if (mp_ofs != old_mp_ofs)
-			memmove((u8 *)a + mp_ofs, (u8 *)a + old_mp_ofs, mp_size);
+		if (name_ofs > old_name_ofs) {
+			/* Payload offsets increased: move mapping pairs first. */
+			if (mp_ofs != old_mp_ofs)
+				memmove((u8 *)a + mp_ofs,
+						(u8 *)a + old_mp_ofs,
+						mp_size);
+			if (a->name_length && name_ofs != old_name_ofs)
+				memmove((u8 *)a + name_ofs,
+						(u8 *)a + old_name_ofs,
+						a->name_length *
+							sizeof(__le16));
+		} else {
+			/* Payload offsets decreased or unchanged: move name first. */
+			if (a->name_length && name_ofs != old_name_ofs)
+				memmove((u8 *)a + name_ofs,
+						(u8 *)a + old_name_ofs,
+						a->name_length *
+							sizeof(__le16));
+			if (mp_ofs != old_mp_ofs)
+				memmove((u8 *)a + mp_ofs,
+						(u8 *)a + old_mp_ofs,
+						mp_size);
+		}
 	}
 
 	err = ntfs_attr_record_resize(ctx->mrec, a, arec_size);