[uml-devel] [PATCH 02/11] uml - hostfs: fix double free

[Paolo 'B. G. <bla...@ya...>]

From: Paolo 'Blaisorblade' Giarrusso <bla...@ya...>

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 <wst...@po...>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <bla...@ya...>
---

 fs/hostfs/hostfs_kern.c |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
index e965eb1..6f10e43 100644
--- 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;
=20
 	HOSTFS_I(root_inode)->host_filename =3D name;
+	/* Avoid that in the error path, iput(root_inode) frees again name thro=
ugh
+	 * hostfs_destroy_inode! */
+	name =3D NULL;
=20
 	err =3D -ENOMEM;
 	sb->s_root =3D 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 u=
s */
                 dput(sb->s_root);
                 sb->s_root =3D NULL;
-		goto out_free;
+		goto out;
         }
=20
 	return(0);