[Cluster-devel] [libgfs2 PATCH] libgfs2: Check block range when inserting into rgrp tree

[Bob Peterson]

Hi,

This patch adds checks to function rindex_read to make sure the
rgrp starting address isn't grossly outside the file system.
It may be in the case of severely corrupt file systems from fsck.
If we added them to the rgrp tree, our calculations will get
screwed up, eventually causing a segfault.

Regards,

Bob Peterson
Red Hat File Systems

Signed-off-by: Bob Peterson <rpeterso at redhat.com>
---
diff --git a/gfs2/libgfs2/super.c b/gfs2/libgfs2/super.c
index b956366..73354ff 100644
--- a/gfs2/libgfs2/super.c
+++ b/gfs2/libgfs2/super.c
@@ -166,6 +166,12 @@ int rindex_read(struct gfs2_sbd *sdp, int fd, int *count1, int *sane)
 			return -1;
 
 		gfs2_rindex_in(&ri, (char *)&buf.bufgfs2);
+		if (gfs2_check_range(sdp, ri.ri_addr) != 0) {
+			*sane = 0;
+			if (prev_rgd == NULL)
+				return -1;
+			ri.ri_addr = prev_rgd->ri.ri_addr + prev_rgd->length;
+		}
 		rgd = rgrp_insert(&sdp->rgtree, ri.ri_addr);
 		memcpy(&rgd->ri, &ri, sizeof(struct gfs2_rindex));