diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2019-04-10 14:04:34 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-05-25 18:22:25 +0200 |
| commit | fa42fde1f8e6da596de8e0bb1e353bc8ce000bc2 (patch) | |
| tree | fcd7d6c1d658fc6253a3dc2258e10a15e1e30e7b | |
| parent | cf0259f7662a84b20ac3a71b9e1cc9e918e9a244 (diff) | |
apparmorfs: fix use-after-free on symlink traversal
[ Upstream commit f51dcd0f621caac5380ce90fbbeafc32ce4517ae ]
symlink body shouldn't be freed without an RCU delay. Switch apparmorfs
to ->destroy_inode() and use of call_rcu(); free both the inode and symlink
body in the callback.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | security/apparmor/apparmorfs.c | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c index 3f80a684c232..665853dd517c 100644 --- a/security/apparmor/apparmorfs.c +++ b/security/apparmor/apparmorfs.c @@ -123,17 +123,22 @@ static int aafs_show_path(struct seq_file *seq, struct dentry *dentry) return 0; } -static void aafs_evict_inode(struct inode *inode) +static void aafs_i_callback(struct rcu_head *head) { - truncate_inode_pages_final(&inode->i_data); - clear_inode(inode); + struct inode *inode = container_of(head, struct inode, i_rcu); if (S_ISLNK(inode->i_mode)) kfree(inode->i_link); + free_inode_nonrcu(inode); +} + +static void aafs_destroy_inode(struct inode *inode) +{ + call_rcu(&inode->i_rcu, aafs_i_callback); } static const struct super_operations aafs_super_ops = { .statfs = simple_statfs, - .evict_inode = aafs_evict_inode, + .destroy_inode = aafs_destroy_inode, .show_path = aafs_show_path, }; |