Fix various issues with update_mtab(), causing 'mount -f' to not update mtab

as expected, bug #105641.

(Portage version: 2.0.52-r1)

3 files changed, 67 insertions, 2 deletions

diff --git a/sys-apps/util-linux/ChangeLog b/sys-apps/util-linux/ChangeLog
index 965ee6569e8a..ff136f3ad650 100644
--- a/sys-apps/util-linux/ChangeLog
+++ b/sys-apps/util-linux/ChangeLog
@@ -1,6 +1,12 @@
 # ChangeLog for sys-apps/util-linux
 # Copyright 1999-2005 Gentoo Foundation; Distributed under the GPL v2
-# $Header: /var/cvsroot/gentoo-x86/sys-apps/util-linux/ChangeLog,v 1.111 2005/09/14 03:17:38 vapier Exp $
+# $Header: /var/cvsroot/gentoo-x86/sys-apps/util-linux/ChangeLog,v 1.112 2005/09/14 09:07:25 azarah Exp $
+
+  14 Sep 2005; Martin Schlemmer <azarah@gentoo.org>
+  +files/util-linux-2.12q-update_mtab-fixes.patch,
+  util-linux-2.12q-r2.ebuild:
+  Fix various issues with update_mtab(), causing 'mount -f' to not update mtab
+  as expected, bug #105641.
 
   14 Sep 2005; Mike Frysinger <vapier@gentoo.org>
   +files/util-linux-2.12q-umount-dont-write-mtab-with-remount.patch,
diff --git a/sys-apps/util-linux/files/util-linux-2.12q-update_mtab-fixes.patch b/sys-apps/util-linux/files/util-linux-2.12q-update_mtab-fixes.patch
new file mode 100644
index 000000000000..15969461f2f0
--- /dev/null
+++ b/sys-apps/util-linux/files/util-linux-2.12q-update_mtab-fixes.patch
@@ -0,0 +1,56 @@
+This fixes a few issues with update_mtab():
+- If it is a remount, and only mnt_opts needs updating, mc->m.mnt_opts is set
+  to point to instead->mnt_opts, rather than allocating a new string, which
+  would cause a double free if the caller actually freed the passed mnt_opts,
+  as we free mc->m.mnt_opts before returning to the caller.
+- Mostly the same issue as above.  If mtab does not contain the new entry, then
+  absent->m is set to point to instead, which would have cause a double free
+  if absent was inserted properly into the linked list, since we free all
+  elements of absent before returning to the caller.
+- If mtab does not contain the new entry, then only mc0->prev is updated to
+  point to absent, but not the old mc0->prev's nxt pointer.  Because we then
+  use the nxt pointers to write the new mtab, absent is not added to the new
+  mtab.
+- If mtab is empty, absent->prev should be set to mc0, and not mc0->prev, as
+  it will be NULL.
+
+Patch by Martin Schlemmer <azarah@gentoo.za.org>
+
+
+--- util-linux-2.12q/mount/fstab.c	2005-09-14 08:22:34.000000000 +0200
++++ util-linux-2.12q.az/mount/fstab.c	2005-09-14 10:37:54.000000000 +0200
+@@ -604,15 +604,30 @@ update_mtab (const char *dir, struct my_
+ 				free(mc);
+ 			}
+ 		} else {
+-			/* A remount */
+-			mc->m.mnt_opts = instead->mnt_opts;
++			/* A remount.  Need to alloc memory, else we might
++			 * run into issues if both we and the caller frees
++			 * mnt_opts ... */
++			mc->m.mnt_opts = xstrdup(instead->mnt_opts);
+ 		}
+ 	} else if (instead) {
+ 		/* not found, add a new entry */
+ 		absent = xmalloc(sizeof(*absent));
+-		absent->m = *instead;
++		/* Cannot just set absent->m to instead, as we free absent
++		 * below, and the caller might free instead */
++		absent->m.mnt_fsname = xstrdup(instead->mnt_fsname);
++		absent->m.mnt_dir = xstrdup(instead->mnt_dir);
++		absent->m.mnt_type = xstrdup(instead->mnt_type);
++		absent->m.mnt_opts = xstrdup(instead->mnt_opts);
++		absent->m.mnt_freq = instead->mnt_freq;
++		absent->m.mnt_passno = instead->mnt_passno;
++
+ 		absent->nxt = mc0;
+-		absent->prev = mc0->prev;
++		if (mc0->prev != NULL) {
++			absent->prev = mc0->prev;
++			mc0->prev->nxt = absent;
++		} else {
++			absent->prev = mc0;
++		}
+ 		mc0->prev = absent;
+ 		if (mc0->nxt == NULL)
+ 			mc0->nxt = absent;
diff --git a/sys-apps/util-linux/util-linux-2.12q-r2.ebuild b/sys-apps/util-linux/util-linux-2.12q-r2.ebuild
index 8a540f925655..57bd4839e636 100644
--- a/sys-apps/util-linux/util-linux-2.12q-r2.ebuild
+++ b/sys-apps/util-linux/util-linux-2.12q-r2.ebuild
@@ -1,6 +1,6 @@
 # Copyright 1999-2005 Gentoo Foundation
 # Distributed under the terms of the GNU General Public License v2
-# $Header: /var/cvsroot/gentoo-x86/sys-apps/util-linux/util-linux-2.12q-r2.ebuild,v 1.3 2005/09/14 03:17:38 vapier Exp $
+# $Header: /var/cvsroot/gentoo-x86/sys-apps/util-linux/util-linux-2.12q-r2.ebuild,v 1.4 2005/09/14 09:07:25 azarah Exp $
 
 inherit eutils flag-o-matic toolchain-funcs
 
@@ -65,6 +65,9 @@ src_unpack() {
 	# Respect -n with -r and umount #98675
 	epatch "${FILESDIR}"/${PN}-2.12q-umount-dont-write-mtab-with-remount.patch
 
+	# A few fixes to beat update_mtab() into submission.
+	epatch "${FILESDIR}"/${PN}-2.12q-update_mtab-fixes.patch
+
 	# Fix unreadable df output when using devfs ... this check is kind of 
 	# a hack, but whatever, the output isnt critical at all :P
 	[[ -e /dev/.devfsd ]] && epatch "${FILESDIR}"/no-symlink-resolve.patch