Bogus KASSERT() in LFS?

[Martin Husemann <martin%duskware.de@localhost>]

Disclaimer: I know nothing about LFS, but it seems to me that there is no
guarantee for "curpg" to not be NULL in the following code from
src/sys/ufs/lfs/lfs_vnops.c:

        while (by_list || soff < MIN(blkeof, endoffset)) {
                if (by_list) {
                        /*
                         * Find the first page in a block.  Skip
                         * blocks outside our area of interest or beyond
                         * the end of file.
                         */
                        KASSERT(curpg == NULL ||
                            (curpg->flags & PG_MARKER) == 0);


and actually some ATF tests die for me with SIGSEGV inside the KASSERT.
So, would this patch be ok?

Index: lfs_vnops.c
===================================================================
RCS file: /cvsroot/src/sys/ufs/lfs/lfs_vnops.c,v
retrieving revision 1.233
diff -u -r1.233 lfs_vnops.c
--- lfs_vnops.c 2 Jan 2011 05:09:32 -0000       1.233
+++ lfs_vnops.c 5 Jan 2011 15:07:00 -0000
@@ -1860,7 +1860,8 @@
                         * blocks outside our area of interest or beyond
                         * the end of file.
                         */
-                       KASSERT((curpg->flags & PG_MARKER) == 0);
+                       KASSERT(curpg == NULL ||
+                           (curpg->flags & PG_MARKER) == 0);
                        if (pages_per_block > 1) {
                                while (curpg &&
                                    ((curpg->offset & fs->lfs_bmask) ||



Martin