Commit 4c62bd9c authored Oct 08, 2018 by Andrew Price Committed by Bob Peterson Oct 08, 2018

gfs2: Don't leave s_fs_info pointing to freed memory in init_sbd



When alloc_percpu() fails, sdp gets freed but sb->s_fs_info still points
to the same address. Move the assignment after that error check so that
s_fs_info can only point to a valid sdp or NULL, which is checked for
later in the error path, in gfs2_kill_super().

Reported-by:  <syzbot+dcb8b3587445007f5808@syzkaller.appspotmail.com>
Signed-off-by: Andrew Price <anprice@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>

parent e54c78a2

fs/gfs2/ops_fstype.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -72,13 +72,13 @@ static struct gfs2_sbd init_sbd(struct super_block sb)
		if (!sdp)
		return NULL;

		sb->s_fs_info = sdp;
		sdp->sd_vfs = sb;
		sdp->sd_lkstats = alloc_percpu(struct gfs2_pcpu_lkstats);
		if (!sdp->sd_lkstats) {
		kfree(sdp);
		return NULL;
		}
		sb->s_fs_info = sdp;

		set_bit(SDF_NOJOURNALID, &sdp->sd_flags);
		gfs2_tune_init(&sdp->sd_tune);

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