[PATCH AUTOSEL 4.9 14/17] ext4: Make sure quota files are not grabbed accidentally
From: Sasha Levin <sashal@kernel.org>
Date: 2021-09-10 01:05:36
Also in:
linux-ext4, lkml
Subsystem:
ext4 file system, filesystems (vfs and infrastructure), the rest · Maintainers:
"Theodore Ts'o", Alexander Viro, Christian Brauner, Linus Torvalds
From: Jan Kara <jack@suse.cz> [ Upstream commit bd2c38cf1726ea913024393a0d11f2e2a3f4c180 ] If ext4 filesystem is corrupted so that quota files are linked from directory hirerarchy, bad things can happen. E.g. quota files can get corrupted or deleted. Make sure we are not grabbing quota file inodes when we expect normal inodes. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Link: https://lore.kernel.org/r/20210812133122.26360-1-jack@suse.cz (local) Signed-off-by: Sasha Levin <sashal@kernel.org> --- fs/ext4/inode.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 79c067f74253..6459bdbbc3f2 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c@@ -4489,6 +4489,7 @@ struct inode *__ext4_iget(struct super_block *sb, unsigned long ino, struct ext4_iloc iloc; struct ext4_inode *raw_inode; struct ext4_inode_info *ei; + struct ext4_super_block *es = EXT4_SB(sb)->s_es; struct inode *inode; journal_t *journal = EXT4_SB(sb)->s_journal; long ret;
@@ -4499,9 +4500,12 @@ struct inode *__ext4_iget(struct super_block *sb, unsigned long ino, projid_t i_projid; if ((!(flags & EXT4_IGET_SPECIAL) && - (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)) || + ((ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO) || + ino == le32_to_cpu(es->s_usr_quota_inum) || + ino == le32_to_cpu(es->s_grp_quota_inum) || + ino == le32_to_cpu(es->s_prj_quota_inum))) || (ino < EXT4_ROOT_INO) || - (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))) { + (ino > le32_to_cpu(es->s_inodes_count))) { if (flags & EXT4_IGET_HANDLE) return ERR_PTR(-ESTALE); __ext4_error(sb, function, line,
--
2.30.2