From: Andrey Albershteyn <aalbersh@kernel.org>
Date: Thu, 9 Jul 2026 15:24:07 +0000 (+0200)
Subject: xfs: fix null pointer dereference in tracepoint
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=9202ee546b0cd71004eed7598546efe4660097da;p=thirdparty%2Fkernel%2Flinux.git

xfs: fix null pointer dereference in tracepoint

If dfp is not NULL we exit early here, when dfp is NULL it's allocated
in xfs_defer_alloc() but not assigned. The tracepoint tries to
dereference members of dfp struct.

Signed-off-by: Andrey Albershteyn <aalbersh@kernel.org>
Cc: stable@vger.kernel.org # v6.8
Fixes: 3f3cec031099c3 ("xfs: force small EFIs for reaping btree extents")
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
---

diff --git a/fs/xfs/libxfs/xfs_defer.c b/fs/xfs/libxfs/xfs_defer.c
index c6909716b041..89501e8bd2f8 100644
--- a/fs/xfs/libxfs/xfs_defer.c
+++ b/fs/xfs/libxfs/xfs_defer.c
@@ -878,7 +878,7 @@ xfs_defer_add_barrier(
 	if (dfp)
 		return;
 
-	xfs_defer_alloc(&tp->t_dfops, &xfs_barrier_defer_type);
+	dfp = xfs_defer_alloc(&tp->t_dfops, &xfs_barrier_defer_type);
 
 	trace_xfs_defer_add_item(tp->t_mountp, dfp, NULL);
 }