From 34b07840565004cfa444e165e88bf77a5cbcdb25 Mon Sep 17 00:00:00 2001
From: Djalal Harouni <tixxdz@opendz.org>
Date: Mon, 9 Jan 2012 15:58:37 +0100
Subject: ext2: protect inode changes in the SETVERSION and SETFLAGS ioctls
Unlock mutex after i_flags and i_ctime updates in the EXT2_IOC_SETFLAGS
ioctl.
Use i_mutex in the EXT2_IOC_SETVERSION ioctl to protect i_ctime and
i_generation updates and make the ioctl consistent since i_mutex is
also used in other places to protect timestamps and inode changes.
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Djalal Harouni <tixxdz@opendz.org>
Signed-off-by: Jan Kara <jack@suse.cz>
---
fs/ext2/ioctl.c | 22 ++++++++++++++++------
1 file changed, 16 insertions(+), 6 deletions(-)
(limited to 'fs/ext2')
diff --git a/fs/ext2/ioctl.c b/fs/ext2/ioctl.c
index 1089f760c847..2de655f5d625 100644
--- a/fs/ext2/ioctl.c
+++ b/fs/ext2/ioctl.c
@@ -77,10 +77,11 @@ long ext2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
flags = flags & EXT2_FL_USER_MODIFIABLE;
flags |= oldflags & ~EXT2_FL_USER_MODIFIABLE;
ei->i_flags = flags;
- mutex_unlock(&inode->i_mutex);
ext2_set_inode_flags(inode);
inode->i_ctime = CURRENT_TIME_SEC;
+ mutex_unlock(&inode->i_mutex);
+
mark_inode_dirty(inode);
setflags_out:
mnt_drop_write_file(filp);
@@ -88,20 +89,29 @@ setflags_out:
}
case EXT2_IOC_GETVERSION:
return put_user(inode->i_generation, (int __user *) arg);
- case EXT2_IOC_SETVERSION:
+ case EXT2_IOC_SETVERSION: {
+ __u32 generation;
+
if (!inode_owner_or_capable(inode))
return -EPERM;
ret = mnt_want_write_file(filp);
if (ret)
return ret;
- if (get_user(inode->i_generation, (int __user *) arg)) {
+ if (get_user(generation, (int __user *) arg)) {
ret = -EFAULT;
- } else {
- inode->i_ctime = CURRENT_TIME_SEC;
- mark_inode_dirty(inode);
+ goto setversion_out;
}
+
+ mutex_lock(&inode->i_mutex);
+ inode->i_ctime = CURRENT_TIME_SEC;
+ inode->i_generation = generation;
+ mutex_unlock(&inode->i_mutex);
+
+ mark_inode_dirty(inode);
+setversion_out:
mnt_drop_write_file(filp);
return ret;
+ }
case EXT2_IOC_GETRSVSZ:
if (test_opt(inode->i_sb, RESERVATION)
&& S_ISREG(inode->i_mode)
--
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