diff options
| author | Dongliang Mu <mudongliangabcd@gmail.com> | 2022-08-16 07:08:58 +0300 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2022-09-02 00:30:24 +0300 |
| commit | 2e488f13755ffbb60f307e991b27024716a33b29 (patch) | |
| tree | fa967a2ec7ee9bfdfddba2f6e73f91d7bbff075c /fs/inode.c | |
| parent | 568035b01cfb107af8d2e4bd2fb9aea22cf5b868 (diff) | |
| download | linux-2e488f13755ffbb60f307e991b27024716a33b29.tar.xz | |
fs: fix UAF/GPF bug in nilfs_mdt_destroy
In alloc_inode, inode_init_always() could return -ENOMEM if
security_inode_alloc() fails, which causes inode->i_private
uninitialized. Then nilfs_is_metadata_file_inode() returns
true and nilfs_free_inode() wrongly calls nilfs_mdt_destroy(),
which frees the uninitialized inode->i_private
and leads to crashes(e.g., UAF/GPF).
Fix this by moving security_inode_alloc just prior to
this_cpu_inc(nr_inodes)
Link: https://lkml.kernel.org/r/CAFcO6XOcf1Jj2SeGt=jJV59wmhESeSKpfR0omdFRq+J9nD1vfQ@mail.gmail.com
Reported-by: butt3rflyh4ck <butterflyhuangxx@gmail.com>
Reported-by: Hao Sun <sunhao.th@gmail.com>
Reported-by: Jiacheng Xu <stitch@zju.edu.cn>
Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs/inode.c')
| -rw-r--r-- | fs/inode.c | 7 |
1 files changed, 3 insertions, 4 deletions
diff --git a/fs/inode.c b/fs/inode.c index 6462276dfdf0..5559a2983341 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -192,8 +192,6 @@ int inode_init_always(struct super_block *sb, struct inode *inode) inode->i_wb_frn_history = 0; #endif - if (security_inode_alloc(inode)) - goto out; spin_lock_init(&inode->i_lock); lockdep_set_class(&inode->i_lock, &sb->s_type->i_lock_key); @@ -228,11 +226,12 @@ int inode_init_always(struct super_block *sb, struct inode *inode) inode->i_fsnotify_mask = 0; #endif inode->i_flctx = NULL; + + if (unlikely(security_inode_alloc(inode))) + return -ENOMEM; this_cpu_inc(nr_inodes); return 0; -out: - return -ENOMEM; } EXPORT_SYMBOL(inode_init_always); |