File xfsprogs-xfs_repair-initialize-realloced-bplist-in-longform_d.patch of Package xfsprogs.35236

From 1624c340a53012b4afd1194d990890c140e3fb66 Mon Sep 17 00:00:00 2001
From: Eric Sandeen <sandeen@redhat.com>
Date: Tue, 30 Oct 2018 16:51:55 -0500
Subject: [PATCH] xfs_repair: initialize realloced bplist in
 longform_dir2_entry_check
Git-commit: 1624c340a53012b4afd1194d990890c140e3fb66
Patch-mainline: v4.19.0-rc1
References: bsc#1187832

If we need to realloc the bplist[] array holding buffers for a given
directory, we don't initialize the new slots.  This causes a problem
if the directory has holes, because those slots never get filled in.

At the end of the function we call libxfs_putbuf for every non-null
slot, and any uninitialized slots are segfault landmines.

Make sure we initialize all new slots to NULL for this reason.

Reported-by: Oleg Davydov <burunduk3@gmail.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Acked-by: Anthony Iliopoulos <ailiop@suse.com>

---
 repair/phase6.c | 5 +++++
 1 file changed, 5 insertions(+)

Index: xfsprogs-4.15.0/repair/phase6.c
===================================================================
--- xfsprogs-4.15.0.orig/repair/phase6.c
+++ xfsprogs-4.15.0/repair/phase6.c
@@ -2300,6 +2300,8 @@ longform_dir2_entry_check(xfs_mount_t	*m
 
 		db = xfs_dir2_da_to_db(mp->m_dir_geo, da_bno);
 		if (db >= num_bps) {
+			int last_size = num_bps;
+
 			/* more data blocks than expected */
 			num_bps = db + 1;
 			bplist = realloc(bplist, num_bps * sizeof(struct xfs_buf*));
@@ -2307,6 +2309,9 @@ longform_dir2_entry_check(xfs_mount_t	*m
 				do_error(_("realloc failed in %s (%zu bytes)\n"),
 					__func__,
 					num_bps * sizeof(struct xfs_buf*));
+			/* Initialize the new elements */
+			for (i = last_size; i < num_bps; i++)
+				bplist[i] = NULL;
 		}
 
 		if (isblock)