[PATCH] uml: hostfs: fix double free

Fix double free in the error path - when name is assigned into root_inode we
do not own it any more and we must not kfree() it - see patch for details.

Thanks to William Stearns for the initial report.

CC: William Stearns <wstearns@pobox.com>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
index e965eb11d76fa4e92034ceb0bcba4e69f1f0271d..6f10e43746f901f7b74eb917d00012b203ab11da 100644 (file)
--- a/fs/hostfs/hostfs_kern.c
+++ b/fs/hostfs/hostfs_kern.c
@@ -966,6 +966,9 @@ static int hostfs_fill_sb_common(struct super_block *sb, void *d, int silent)
                goto out_put;
 
        HOSTFS_I(root_inode)->host_filename = name;
+       /* Avoid that in the error path, iput(root_inode) frees again name through
+        * hostfs_destroy_inode! */
+       name = NULL;
 
        err = -ENOMEM;
        sb->s_root = d_alloc_root(root_inode);
@@ -977,7 +980,7 @@ static int hostfs_fill_sb_common(struct super_block *sb, void *d, int silent)
                 /* No iput in this case because the dput does that for us */
                 dput(sb->s_root);
                 sb->s_root = NULL;
-               goto out_free;
+               goto out;
         }
 
        return(0);