Commit 6e589291 authored Feb 11, 2019 by Theodore Ts'o

ext4: disallow files with EXT4_JOURNAL_DATA_FL from EXT4_IOC_SWAP_BOOT

A malicious/clueless root user can use EXT4_IOC_SWAP_BOOT to force a
corner casew which can lead to the file system getting corrupted.
There's no usefulness to allowing this, so just prohibit this case.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

parent abdc644e

fs/ext4/ioctl.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -132,6 +132,7 @@ static long swap_inode_boot_loader(struct super_block *sb,

		if (inode->i_nlink != 1 \|\| !S_ISREG(inode->i_mode) \|\|
		IS_SWAPFILE(inode) \|\| IS_ENCRYPTED(inode) \|\|
		(EXT4_I(inode)->i_flags & EXT4_JOURNAL_DATA_FL) \|\|
		ext4_has_inline_data(inode)) {
		err = -EINVAL;
		goto journal_err_out;

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