From 34b07840565004cfa444e165e88bf77a5cbcdb25 Mon Sep 17 00:00:00 2001 From: Djalal Harouni Date: Mon, 9 Jan 2012 15:58:37 +0100 Subject: [PATCH] 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 Cc: Jan Kara Signed-off-by: Djalal Harouni Signed-off-by: Jan Kara --- fs/ext2/ioctl.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) 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) -- 2.39.5