svn commit: r237490 - stable/9/sys/ufs/ffs

[Edward Tomasz Napierala]

Author: trasz
Date: Sat Jun 23 18:26:23 2012
New Revision: 237490
URL: http://svn.freebsd.org/changeset/base/237490

Log:
  MFC r234036:
  
  Fix panic in ffs_reload(), which may happen when read-only filesystem
  gets resized and then reloaded.
  
  MFC r234537:
  
  Fix use-after-free introduced in r234036.

Modified:
  stable/9/sys/ufs/ffs/ffs_vfsops.c
Directory Properties:
  stable/9/sys/   (props changed)

Modified: stable/9/sys/ufs/ffs/ffs_vfsops.c
==============================================================================
--- stable/9/sys/ufs/ffs/ffs_vfsops.c	Sat Jun 23 18:07:48 2012	(r237489)
+++ stable/9/sys/ufs/ffs/ffs_vfsops.c	Sat Jun 23 18:26:23 2012	(r237490)
@@ -675,8 +675,14 @@ ffs_reload(struct mount *mp, struct thre
 	/*
 	 * Step 3: re-read summary information from disk.
 	 */
-	blks = howmany(fs->fs_cssize, fs->fs_fsize);
-	space = fs->fs_csp;
+	size = fs->fs_cssize;
+	blks = howmany(size, fs->fs_fsize);
+	if (fs->fs_contigsumsize > 0)
+		size += fs->fs_ncg * sizeof(int32_t);
+	size += fs->fs_ncg * sizeof(u_int8_t);
+	free(fs->fs_csp, M_UFSMNT);
+	space = malloc((u_long)size, M_UFSMNT, M_WAITOK);
+	fs->fs_csp = space;
 	for (i = 0; i < blks; i += fs->fs_frag) {
 		size = fs->fs_bsize;
 		if (i + fs->fs_frag > blks)
@@ -693,10 +699,14 @@ ffs_reload(struct mount *mp, struct thre
 	 * We no longer know anything about clusters per cylinder group.
 	 */
 	if (fs->fs_contigsumsize > 0) {
-		lp = fs->fs_maxcluster;
+		fs->fs_maxcluster = lp = space;
 		for (i = 0; i < fs->fs_ncg; i++)
 			*lp++ = fs->fs_contigsumsize;
+		space = lp;
 	}
+	size = fs->fs_ncg * sizeof(u_int8_t);
+	fs->fs_contigdirs = (u_int8_t *)space;
+	bzero(fs->fs_contigdirs, size);
 
 loop:
 	MNT_VNODE_FOREACH_ALL(vp, mp, mvp) {