[PATCH 1/4] don't leak m_fsname/m_rtname/m_logname

Christoph Hellwig
2008-05-25T19:06:57Z

Add a helper to free the m_fsname/m_rtname/m_logname allocations and use
it properly for all mount failure cases. Also switch the allocations
for these to kstrdup while we're at it.

Signed-off-by: Christoph Hellwig <hch@lst.de>

Index: linux-2.6-xfs/fs/xfs/linux-2.6/xfs_super.c
===================================================================
--- linux-2.6-xfs.orig/fs/xfs/linux-2.6/xfs_super.c 2008-05-22 19:30:25.000000000 +0200
+++ linux-2.6-xfs/fs/xfs/linux-2.6/xfs_super.c 2008-05-22 19:30:44.000000000 +0200
@@ -1079,6 +1079,15 @@ xfssyncd(
}

STATIC void
+xfs_free_fsname(
+ struct xfs_mount *mp)
+{
+ kfree(mp->m_fsname);
+ kfree(mp->m_rtname);
+ kfree(mp->m_logname);
+}
+
+STATIC void
xfs_fs_put_super(
struct super_block *sb)
{
@@ -1139,6 +1148,7 @@ xfs_fs_put_super(
xfs_close_devices(mp);
xfs_qmops_put(mp);
xfs_dmops_put(mp);
+ xfs_free_fsname(mp);
kfree(mp);
}

@@ -1408,6 +1418,8 @@ xfs_start_flags(
struct xfs_mount_args *ap,
struct xfs_mount *mp)
{
+ int error;
+
/* Values are in BBs */
if ((ap->flags & XFSMNT_NOALIGN) != XFSMNT_NOALIGN) {
/*
@@ -1440,17 +1452,27 @@ xfs_start_flags(
ap->logbufsize);
return XFS_ERROR(EINVAL);
}
+
+ error = ENOMEM;
+
mp->m_logbsize = ap->logbufsize;
mp->m_fsname_len = strlen(ap->fsname) + 1;
- mp->m_fsname = kmem_alloc(mp->m_fsname_len, KM_SLEEP);
- strcpy(mp->m_fsname, ap->fsname);
+
+ mp->m_fsname = kstrdup(ap->fsname, GFP_KERNEL);
+ if (!mp->m_fsname)
+ goto out;
+
if (ap->rtname[0]) {
- mp->m_rtname = kmem_alloc(strlen(ap->rtname) + 1, KM_SLEEP);
- strcpy(mp->m_rtname, ap->rtname);
+ mp->m_rtname = kstrdup(ap->rtname, GFP_KERNEL);
+ if (!mp->m_rtname)
+ goto out_free_fsname;
+
}
+
if (ap->logname[0]) {
- mp->m_logname = kmem_alloc(strlen(ap->logname) + 1, KM_SLEEP);
- strcpy(mp->m_logname, ap->logname);
+ mp->m_logname = kstrdup(ap->logname, GFP_KERNEL);
+ if (!mp->m_logname)
+ goto out_free_rtname;
}

if (ap->flags & XFSMNT_WSYNC)
@@ -1523,6 +1545,14 @@ xfs_start_flags(
if (ap->flags & XFSMNT_DMAPI)
mp->m_flags |= XFS_MOUNT_DMAPI;
return 0;
+
+
+ out_free_rtname:
+ kfree(mp->m_rtname);
+ out_free_fsname:
+ kfree(mp->m_fsname);
+ out:
+ return error;
}

/*
@@ -1683,10 +1713,10 @@ xfs_fs_fill_super(
*/
error = xfs_start_flags(args, mp);
if (error)
- goto out_destroy_counters;
+ goto out_free_fsname;
error = xfs_readsb(mp, flags);
if (error)
- goto out_destroy_counters;
+ goto out_free_fsname;
error = xfs_finish_flags(args, mp);
if (error)
goto out_free_sb;
@@ -1748,7 +1778,8 @@ xfs_fs_fill_super(
xfs_filestream_unmount(mp);
out_free_sb:
xfs_freesb(mp);
- out_destroy_counters:
+ out_free_fsname:
+ xfs_free_fsname(mp);
xfs_icsb_destroy_counters(mp);
xfs_close_devices(mp);
out_put_qmops:
@@ -1784,7 +1815,7 @@ xfs_fs_fill_super(
IRELE(mp->m_rootip);

xfs_unmountfs(mp);
- goto out_destroy_counters;
+ goto out_free_fsname;
}

STATIC int
Index: linux-2.6-xfs/fs/xfs/xfs_mount.c
===================================================================
--- linux-2.6-xfs.orig/fs/xfs/xfs_mount.c 2008-05-22 19:31:25.000000000 +0200
+++ linux-2.6-xfs/fs/xfs/xfs_mount.c 2008-05-22 19:31:29.000000000 +0200
@@ -146,13 +146,6 @@ xfs_mount_free(
mutex_destroy(&mp->m_growlock);
if (mp->m_quotainfo)
XFS_QM_DONE(mp);
-
- if (mp->m_fsname != NULL)
- kmem_free(mp->m_fsname);
- if (mp->m_rtname != NULL)
- kmem_free(mp->m_rtname);
- if (mp->m_logname != NULL)
- kmem_free(mp->m_logname);
}

/*