diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2019-04-10 21:04:34 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-05-25 19:25:35 +0300 |
| commit | ffbbe8e8bde999133a06de73a2f3bce03c8c0001 (patch) | |
| tree | 215c1285570902ba25bf79b92e150a4b7f60a53c /security | |
| parent | 0319e32b053aa35ac0f7c38e573d6eece5c8df7c (diff) | |
| download | linux-ffbbe8e8bde999133a06de73a2f3bce03c8c0001.tar.xz | |
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>
Diffstat (limited to 'security')
| -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 0e03377bb83e..dd746bd69a9b 100644 --- a/security/apparmor/apparmorfs.c +++ b/security/apparmor/apparmorfs.c @@ -126,17 +126,22 @@ 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, }; |