+ ocfs2-abstract-the-fast-symlink-dinode-guard-and-size-check.patch added to mm-nonmm-unstable branch

+ ocfs2-abstract-the-fast-symlink-dinode-guard-and-size-check.patch added to mm-nonmm-unstable branch

[Andrew Morton]

The patch titled
     Subject: ocfs2: abstract the fast symlink dinode guard and size check
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     ocfs2-abstract-the-fast-symlink-dinode-guard-and-size-check.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/ocfs2-abstract-the-fast-symlink-dinode-guard-and-size-check.patch

This patch will later appear in the mm-nonmm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Joseph Qi <joseph.qi@linux.alibaba.com>
Subject: ocfs2: abstract the fast symlink dinode guard and size check
Date: Mon, 09 Nov 2026 20:21:03 +0800

Introduce ocfs2_dinode_is_fast_symlink() for the S_ISLNK with no
allocated clusters test that selects the id2.i_symlink union arm, and
ocfs2_dinode_has_oversized_fast_symlink() for the i_size bound.

The guard is deliberately not shared with the similar test inside
ocfs2_dinode_has_extents(), which additionally requires a non-zero
i_size.  A zero-length, zero-cluster symlink currently falls through to
the extent list checks, and reusing one predicate for both would change
that.

No functional change intended.

Link: https://lore.kernel.org/20261109122121.21473-14-joseph.qi@linux.alibaba.com
Signed-off-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Heming Zhao <heming.zhao@suse.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
---

 fs/ocfs2/inode.c |   20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

--- a/fs/ocfs2/inode.c~ocfs2-abstract-the-fast-symlink-dinode-guard-and-size-check
+++ a/fs/ocfs2/inode.c
@@ -192,6 +192,21 @@ static bool ocfs2_dinode_has_inline_size
 	return le64_to_cpu(di->i_size) > le16_to_cpu(di->id2.i_data.id_count);
 }
 
+/*
+ * Unlike the similar test in ocfs2_dinode_has_extents(), this does not require
+ * a non-zero i_size: a zero-length fast symlink is still validated here.
+ */
+static bool ocfs2_dinode_is_fast_symlink(struct ocfs2_dinode *di)
+{
+	return S_ISLNK(le16_to_cpu(di->i_mode)) && !le32_to_cpu(di->i_clusters);
+}
+
+static bool ocfs2_dinode_has_oversized_fast_symlink(struct super_block *sb,
+						    struct ocfs2_dinode *di)
+{
+	return le64_to_cpu(di->i_size) >= ocfs2_fast_symlink_chars(sb);
+}
+
 void ocfs2_set_inode_flags(struct inode *inode)
 {
 	unsigned int flags = OCFS2_I(inode)->ip_attr;
@@ -1784,12 +1799,11 @@ int ocfs2_validate_inode_block(struct su
 		}
 	}
 
-	if (S_ISLNK(le16_to_cpu(di->i_mode)) &&
-	    !le32_to_cpu(di->i_clusters)) {
+	if (ocfs2_dinode_is_fast_symlink(di)) {
 		int max_inline = ocfs2_fast_symlink_chars(sb);
 		u64 i_size = le64_to_cpu(di->i_size);
 
-		if (i_size >= max_inline) {
+		if (ocfs2_dinode_has_oversized_fast_symlink(sb, di)) {
 			rc = ocfs2_error(sb,
 					 "Invalid dinode #%llu: fast symlink i_size %llu exceeds max %d\n",
 					 (unsigned long long)bh->b_blocknr,
_

Patches currently in -mm which might be from joseph.qi@linux.alibaba.com are

ocfs2-exempt-orphaned-dinodes-from-the-zero-nlink-check.patch
ocfs2-abstract-the-zero-nlink-or-mode-dinode-check.patch
ocfs2-abstract-the-dinode-i_blkno-mismatch-check.patch
ocfs2-abstract-the-dinode-ocfs2_valid_fl-check.patch
ocfs2-abstract-the-dinode-fs_generation-mismatch-check.patch
ocfs2-abstract-the-dinode-suballoc-slot-checks.patch
ocfs2-abstract-the-dinode-suballoc-bit-check.patch
ocfs2-abstract-the-dinode-orphaned-slot-check.patch
ocfs2-abstract-the-dinode-dio-orphaned-slot-check.patch
ocfs2-abstract-the-inline-data-dinode-guard-and-cluster-check.patch
ocfs2-abstract-the-inline-data-id_count-bound-check.patch
ocfs2-abstract-the-inline-data-i_size-bound-check.patch
ocfs2-abstract-the-fast-symlink-dinode-guard-and-size-check.patch
ocfs2-abstract-the-fast-symlink-nul-termination-check.patch
ocfs2-abstract-the-chain-list-dinode-guard-and-count-check.patch
ocfs2-abstract-the-chain-list-next-free-record-check.patch
ocfs2-abstract-the-chain-list-bits-per-cluster-check.patch
ocfs2-abstract-the-dinode-refcount-location-check.patch
ocfs2-abstract-the-zero-extent-list-count-check.patch
ocfs2-abstract-the-oversized-extent-list-count-check.patch
ocfs2-abstract-the-extent-list-next-free-record-check.patch
ocfs2-report-unrepairable-corruption-from-online-filecheck-fix.patch
ocfs2-check-dinode-nlink-and-mode-in-online-filecheck.patch
ocfs2-check-dinode-suballoc-slot-in-online-filecheck.patch
ocfs2-check-dinode-suballoc-bit-in-online-filecheck.patch
ocfs2-check-dinode-orphaned-slots-in-online-filecheck.patch
ocfs2-check-inline-data-dinodes-in-online-filecheck.patch
ocfs2-check-fast-symlink-dinodes-in-online-filecheck.patch
ocfs2-check-chain-list-dinodes-in-online-filecheck.patch
ocfs2-check-dinode-refcount-location-in-online-filecheck.patch
ocfs2-check-extent-list-dinodes-in-online-filecheck.patch