summaryrefslogtreecommitdiff
path: root/fs
diff options
context:
space:
mode:
authorZhihao Cheng <chengzhihao1@huawei.com>2021-12-27 11:22:32 +0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2022-04-15 14:18:27 +0200
commit14276d38c89a170363e90b6ac0a53c3cf61b87fc (patch)
tree9090a2ce7a6b64008fed24a4d81737ef078e9a43 /fs
parent01df5f7627f1624d6bb0b8c0870a569b32adfbf8 (diff)
ubifs: rename_whiteout: Fix double free for whiteout_ui->data
commit 40a8f0d5e7b3999f096570edab71c345da812e3e upstream. 'whiteout_ui->data' will be freed twice if space budget fail for rename whiteout operation as following process: rename_whiteout dev = kmalloc whiteout_ui->data = dev kfree(whiteout_ui->data) // Free first time iput(whiteout) ubifs_free_inode kfree(ui->data) // Double free! KASAN reports: ================================================================== BUG: KASAN: double-free or invalid-free in ubifs_free_inode+0x4f/0x70 Call Trace: kfree+0x117/0x490 ubifs_free_inode+0x4f/0x70 [ubifs] i_callback+0x30/0x60 rcu_do_batch+0x366/0xac0 __do_softirq+0x133/0x57f Allocated by task 1506: kmem_cache_alloc_trace+0x3c2/0x7a0 do_rename+0x9b7/0x1150 [ubifs] ubifs_rename+0x106/0x1f0 [ubifs] do_syscall_64+0x35/0x80 Freed by task 1506: kfree+0x117/0x490 do_rename.cold+0x53/0x8a [ubifs] ubifs_rename+0x106/0x1f0 [ubifs] do_syscall_64+0x35/0x80 The buggy address belongs to the object at ffff88810238bed8 which belongs to the cache kmalloc-8 of size 8 ================================================================== Let ubifs_free_inode() free 'whiteout_ui->data'. BTW, delete unused assignment 'whiteout_ui->data_len = 0', process 'ubifs_evict_inode() -> ubifs_jnl_delete_inode() -> ubifs_jnl_write_inode()' doesn't need it (because 'inc_nlink(whiteout)' won't be excuted by 'goto out_release', and the nlink of whiteout inode is 0). Fixes: 9e0a1fff8db56ea ("ubifs: Implement RENAME_WHITEOUT") Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com> Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
-rw-r--r--fs/ubifs/dir.c2
1 files changed, 0 insertions, 2 deletions
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
index eeb93f009b28..5134ec246e8f 100644
--- a/fs/ubifs/dir.c
+++ b/fs/ubifs/dir.c
@@ -1431,8 +1431,6 @@ static int do_rename(struct inode *old_dir, struct dentry *old_dentry,
err = ubifs_budget_space(c, &wht_req);
if (err) {
- kfree(whiteout_ui->data);
- whiteout_ui->data_len = 0;
iput(whiteout);
goto out_release;
}