fedora core 6 1.2949 + vserver 2.2.0

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

diff --git a/fs/attr.c b/fs/attr.c
index d63350c..04f5d0b 100644 (file)
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -10,10 +10,14 @@
 #include <linux/mm.h>
 #include <linux/string.h>
 #include <linux/smp_lock.h>
-#include <linux/dnotify.h>
+#include <linux/capability.h>
+#include <linux/fsnotify.h>
 #include <linux/fcntl.h>
 #include <linux/quotaops.h>
 #include <linux/security.h>
+#include <linux/proc_fs.h>
+#include <linux/devpts_fs.h>
+#include <linux/vs_base.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 +59,30 @@ 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, VS_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:
+                       /* maybe allow that in the future? */
+                       vxwprintk(1, "xid=%d messing with the procfs.",
+                               vx_current_xid());
+                       goto error;
+               case DEVPTS_SUPER_MAGIC:
+                       /* devpts is xid tagged */
+                       if (vx_check((xid_t)inode->i_tag, VS_IDENT))
+                               goto fine;
+                       vxwprintk(1, "xid=%d messing with the devpts.",
+                               vx_current_xid());
+                       goto error;
+       }
 fine:
        retval = 0;
 error:
@@ -65,32 +94,29 @@ EXPORT_SYMBOL(inode_change_ok);
 int inode_setattr(struct inode * inode, struct iattr * attr)
 {
        unsigned int ia_valid = attr->ia_valid;
-       int error = 0;
-
-       if (ia_valid & ATTR_SIZE) {
-               if (attr->ia_size != i_size_read(inode)) {
-                       error = vmtruncate(inode, attr->ia_size);
-                       if (error || (ia_valid == ATTR_SIZE))
-                               goto out;
-               } else {
-                       /*
-                        * We skipped the truncate but must still update
-                        * timestamps
-                        */
-                       ia_valid |= ATTR_MTIME|ATTR_CTIME;
-               }
+
+       if (ia_valid & ATTR_SIZE &&
+           attr->ia_size != i_size_read(inode)) {
+               int error = vmtruncate(inode, attr->ia_size);
+               if (error)
+                       return error;
        }
 
        if (ia_valid & ATTR_UID)
                inode->i_uid = attr->ia_uid;
        if (ia_valid & ATTR_GID)
                inode->i_gid = attr->ia_gid;
+       if ((ia_valid & ATTR_TAG) && IS_TAGGED(inode))
+               inode->i_tag = attr->ia_tag;
        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;
 
@@ -99,44 +125,21 @@ int inode_setattr(struct inode * inode, struct iattr * attr)
                inode->i_mode = mode;
        }
        mark_inode_dirty(inode);
-out:
-       return error;
-}
-
-EXPORT_SYMBOL(inode_setattr);
-
-int setattr_mask(unsigned int ia_valid)
-{
-       unsigned long dn_mask = 0;
 
-       if (ia_valid & ATTR_UID)
-               dn_mask |= DN_ATTRIB;
-       if (ia_valid & ATTR_GID)
-               dn_mask |= DN_ATTRIB;
-       if (ia_valid & ATTR_SIZE)
-               dn_mask |= DN_MODIFY;
-       /* both times implies a utime(s) call */
-       if ((ia_valid & (ATTR_ATIME|ATTR_MTIME)) == (ATTR_ATIME|ATTR_MTIME))
-               dn_mask |= DN_ATTRIB;
-       else if (ia_valid & ATTR_ATIME)
-               dn_mask |= DN_ACCESS;
-       else if (ia_valid & ATTR_MTIME)
-               dn_mask |= DN_MODIFY;
-       if (ia_valid & ATTR_MODE)
-               dn_mask |= DN_ATTRIB;
-       return dn_mask;
+       return 0;
 }
+EXPORT_SYMBOL(inode_setattr);
 
 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))
@@ -166,6 +169,9 @@ 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)
@@ -176,17 +182,20 @@ int notify_change(struct dentry * dentry, struct iattr * attr)
                        error = security_inode_setattr(dentry, attr);
                if (!error) {
                        if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
-                           (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid))
+                           (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid) ||
+                           (ia_valid & ATTR_TAG && attr->ia_tag != inode->i_tag))
                                error = DQUOT_TRANSFER(inode, attr) ? -EDQUOT : 0;
                        if (!error)
                                error = inode_setattr(inode, attr);
                }
        }
-       if (!error) {
-               unsigned long dn_mask = setattr_mask(ia_valid);
-               if (dn_mask)
-                       dnotify_parent(dentry, dn_mask);
-       }
+
+       if (ia_valid & ATTR_SIZE)
+               up_write(&dentry->d_inode->i_alloc_sem);
+
+       if (!error)
+               fsnotify_change(dentry, ia_valid);
+
        return error;
 }