vserver 2.0 rc7

[linux-2.6.git] / fs / attr.c

diff --git a/fs/attr.c b/fs/attr.c
index 34dcb1a..3317d4f 100644 (file)
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -14,6 +14,10 @@
 #include <linux/fcntl.h>
 #include <linux/quotaops.h>
 #include <linux/security.h>
+#include <linux/time.h>
+#include <linux/proc_fs.h>
+#include <linux/devpts_fs.h>
+#include <linux/vserver/debug.h>
 
 /* Taken over from the old code... */
 
@@ -35,7 +39,8 @@ int inode_change_ok(struct inode *inode, struct iattr *attr)
 
        /* Make sure caller can chgrp. */
        if ((ia_valid & ATTR_GID) &&
-           (!in_group_p(attr->ia_gid) && attr->ia_gid != inode->i_gid) &&
+           (current->fsuid != inode->i_uid ||
+           (!in_group_p(attr->ia_gid) && attr->ia_gid != inode->i_gid)) &&
            !capable(CAP_CHOWN))
                goto error;
 
@@ -54,6 +59,28 @@ int inode_change_ok(struct inode *inode, struct iattr *attr)
                if (current->fsuid != inode->i_uid && !capable(CAP_FOWNER))
                        goto error;
        }
+
+       /* Check for evil vserver activity */
+       if (vx_check(0, VX_ADMIN))
+               goto fine;
+
+       if (IS_BARRIER(inode)) {
+               vxwprintk(1, "xid=%d messing with the barrier.",
+                       vx_current_xid());
+               goto error;
+       }
+       switch (inode->i_sb->s_magic) {
+               case PROC_SUPER_MAGIC:
+                       vxwprintk(1, "xid=%d messing with the procfs.",
+                               vx_current_xid());
+                       goto error;
+               case DEVPTS_SUPER_MAGIC:
+                       if (vx_check(inode->i_xid, VX_IDENT))
+                               goto fine;
+                       vxwprintk(1, "xid=%d messing with the devpts.",
+                               vx_current_xid());
+                       goto error;
+       }
 fine:
        retval = 0;
 error:
@@ -106,11 +133,14 @@ int inode_setattr(struct inode * inode, struct iattr * attr)
        if (ia_valid & ATTR_XID)
                inode->i_xid = attr->ia_xid;
        if (ia_valid & ATTR_ATIME)
-               inode->i_atime = attr->ia_atime;
+               inode->i_atime = timespec_trunc(attr->ia_atime,
+                                               inode->i_sb->s_time_gran);
        if (ia_valid & ATTR_MTIME)
-               inode->i_mtime = attr->ia_mtime;
+               inode->i_mtime = timespec_trunc(attr->ia_mtime,
+                                               inode->i_sb->s_time_gran);
        if (ia_valid & ATTR_CTIME)
-               inode->i_ctime = attr->ia_ctime;
+               inode->i_ctime = timespec_trunc(attr->ia_ctime,
+                                               inode->i_sb->s_time_gran);
        if (ia_valid & ATTR_MODE) {
                umode_t mode = attr->ia_mode;
 
@@ -154,14 +184,17 @@ int setattr_mask(unsigned int ia_valid)
 int notify_change(struct dentry * dentry, struct iattr * attr)
 {
        struct inode *inode = dentry->d_inode;
-       mode_t mode = inode->i_mode;
+       mode_t mode;
        int error;
-       struct timespec now = CURRENT_TIME;
+       struct timespec now;
        unsigned int ia_valid = attr->ia_valid;
 
        if (!inode)
                BUG();
 
+       mode = inode->i_mode;
+       now = current_fs_time(inode->i_sb);
+
        attr->ia_ctime = now;
        if (!(ia_valid & ATTR_ATIME_SET))
                attr->ia_atime = now;
@@ -190,6 +223,9 @@ int notify_change(struct dentry * dentry, struct iattr * attr)
        if (!attr->ia_valid)
                return 0;
 
+       if (ia_valid & ATTR_SIZE)
+               down_write(&dentry->d_inode->i_alloc_sem);
+
        if (inode->i_op && inode->i_op->setattr) {
                error = security_inode_setattr(dentry, attr);
                if (!error)
@@ -207,6 +243,10 @@ int notify_change(struct dentry * dentry, struct iattr * attr)
                                error = inode_setattr(inode, attr);
                }
        }
+
+       if (ia_valid & ATTR_SIZE)
+               up_write(&dentry->d_inode->i_alloc_sem);
+
        if (!error) {
                unsigned long dn_mask = setattr_mask(ia_valid);
                if (dn_mask)