ext4: fix check of inode in swap_inode_boot_loader

commit 67a11611e1a5211f6569044fbf8150875764d1d0 upstream.

Before really do swap between inode and boot inode, something need to
check to avoid invalid or not permitted operation, like does this inode
has inline data. But the condition check should be protected by inode
lock to avoid change while swapping. Also some other condition will not
change between swapping, but there has no problem to do this under inode
lock.

Signed-off-by: yangerkun <yangerkun@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
[bwh: Backported to 3.16: There's no support or test for filesytem encryption]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This commit is contained in:
yangerkun 2019-02-11 00:02:05 -05:00 committed by syphyr
parent 60777530f8
commit 35ee909ac1
1 changed files with 13 additions and 9 deletions

View File

@ -119,15 +119,6 @@ static long swap_inode_boot_loader(struct super_block *sb,
struct ext4_inode_info *ei_bl;
struct ext4_sb_info *sbi = EXT4_SB(sb);
if (inode->i_nlink != 1 || !S_ISREG(inode->i_mode) ||
IS_SWAPFILE(inode) ||
ext4_has_inline_data(inode))
return -EINVAL;
if (IS_RDONLY(inode) || IS_APPEND(inode) || IS_IMMUTABLE(inode) ||
!inode_owner_or_capable(inode) || !capable(CAP_SYS_ADMIN))
return -EPERM;
inode_bl = ext4_iget(sb, EXT4_BOOT_LOADER_INO, EXT4_IGET_SPECIAL);
if (IS_ERR(inode_bl))
return PTR_ERR(inode_bl);
@ -140,6 +131,19 @@ static long swap_inode_boot_loader(struct super_block *sb,
* that only 1 swap_inode_boot_loader is running. */
lock_two_nondirectories(inode, inode_bl);
if (inode->i_nlink != 1 || !S_ISREG(inode->i_mode) ||
IS_SWAPFILE(inode) ||
ext4_has_inline_data(inode)) {
err = -EINVAL;
goto journal_err_out;
}
if (IS_RDONLY(inode) || IS_APPEND(inode) || IS_IMMUTABLE(inode) ||
!inode_owner_or_capable(inode) || !capable(CAP_SYS_ADMIN)) {
err = -EPERM;
goto journal_err_out;
}
/* Wait for all existing dio workers */
ext4_inode_block_unlocked_dio(inode);
ext4_inode_block_unlocked_dio(inode_bl);