Module Name: src Committed By: snj Date: Tue Aug 4 17:20:58 UTC 2015
Modified Files: src/sys/ufs/lfs [netbsd-7]: lfs_segment.c Log Message: Pull up following revision(s) (requested by dholland in ticket #932): sys/ufs/lfs/lfs_segment.c: revision 1.247 via patch Fix catastrophic bug in lfs_rewind() that changed segment numbers (lfs_curseg/lfs_nextseg in the superblock) using the wrong units. These fields are for whatever reason the start addresses of segments (measured in frags) rather than the segment numbers 0..n. This only apparently affects dumping from a mounted fs; however, it trashes the fs. I would really, really like to have a static analysis tool that can keep track of the units things are measured in, since fs code is full of conversion macros and the macros are named inscrutable things like "sntod" whose letters don't necessarily even correspond to the units they convert. It is surprising that more of these are not wrong. To generate a diff of this commit: cvs rdiff -u -r1.236 -r1.236.4.1 src/sys/ufs/lfs/lfs_segment.c Please note that diffs are not public domain; they are subject to the copyright notices on the relevant files.
Modified files: Index: src/sys/ufs/lfs/lfs_segment.c diff -u src/sys/ufs/lfs/lfs_segment.c:1.236 src/sys/ufs/lfs/lfs_segment.c:1.236.4.1 --- src/sys/ufs/lfs/lfs_segment.c:1.236 Mon Mar 24 13:42:40 2014 +++ src/sys/ufs/lfs/lfs_segment.c Tue Aug 4 17:20:58 2015 @@ -1,4 +1,4 @@ -/* $NetBSD: lfs_segment.c,v 1.236 2014/03/24 13:42:40 hannken Exp $ */ +/* $NetBSD: lfs_segment.c,v 1.236.4.1 2015/08/04 17:20:58 snj Exp $ */ /*- * Copyright (c) 1999, 2000, 2001, 2002, 2003 The NetBSD Foundation, Inc. @@ -60,7 +60,7 @@ */ #include <sys/cdefs.h> -__KERNEL_RCSID(0, "$NetBSD: lfs_segment.c,v 1.236 2014/03/24 13:42:40 hannken Exp $"); +__KERNEL_RCSID(0, "$NetBSD: lfs_segment.c,v 1.236.4.1 2015/08/04 17:20:58 snj Exp $"); #define _VFS_VNODE_PRIVATE /* XXX: check for VI_MARKER, this has to go */ @@ -1702,7 +1702,7 @@ lfs_updatemeta(struct segment *sp) } /* - * Move lfs_offset to a segment earlier than sn. + * Move lfs_offset to a segment earlier than newsn. */ int lfs_rewind(struct lfs *fs, int newsn) @@ -1733,7 +1733,7 @@ lfs_rewind(struct lfs *fs, int newsn) panic("lfs_rewind: no clean segments"); if (newsn >= 0 && sn >= newsn) return ENOENT; - fs->lfs_nextseg = sn; + fs->lfs_nextseg = lfs_sntod(fs, sn); lfs_newseg(fs); fs->lfs_offset = fs->lfs_curseg;