proc: remove obsolete comments

[safe/jmp/linux-2.6] / fs / attr.c

diff --git a/fs/attr.c b/fs/attr.c
index 966b73e..0815e93 100644 (file)
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -12,13 +12,12 @@
 #include <linux/capability.h>
 #include <linux/fsnotify.h>
 #include <linux/fcntl.h>
-#include <linux/quotaops.h>
 #include <linux/security.h>
 
 /* Taken over from the old code... */
 
 /* POSIX UID/GID verification for setting inode attributes. */
-int inode_change_ok(struct inode *inode, struct iattr *attr)
+int inode_change_ok(const struct inode *inode, struct iattr *attr)
 {
        int retval = -EPERM;
        unsigned int ia_valid = attr->ia_valid;
@@ -29,13 +28,13 @@ int inode_change_ok(struct inode *inode, struct iattr *attr)
 
        /* Make sure a caller can chown. */
        if ((ia_valid & ATTR_UID) &&
-           (current->fsuid != inode->i_uid ||
+           (current_fsuid() != inode->i_uid ||
             attr->ia_uid != inode->i_uid) && !capable(CAP_CHOWN))
                goto error;
 
        /* Make sure caller can chgrp. */
        if ((ia_valid & ATTR_GID) &&
-           (current->fsuid != inode->i_uid ||
+           (current_fsuid() != inode->i_uid ||
            (!in_group_p(attr->ia_gid) && attr->ia_gid != inode->i_gid)) &&
            !capable(CAP_CHOWN))
                goto error;
@@ -51,7 +50,7 @@ int inode_change_ok(struct inode *inode, struct iattr *attr)
        }
 
        /* Check for setting the inode time. */
-       if (ia_valid & (ATTR_MTIME_SET | ATTR_ATIME_SET)) {
+       if (ia_valid & (ATTR_MTIME_SET | ATTR_ATIME_SET | ATTR_TIMES_SET)) {
                if (!is_owner_or_cap(inode))
                        goto error;
        }
@@ -60,9 +59,51 @@ fine:
 error:
        return retval;
 }
-
 EXPORT_SYMBOL(inode_change_ok);
 
+/**
+ * inode_newsize_ok - may this inode be truncated to a given size
+ * @inode:     the inode to be truncated
+ * @offset:    the new size to assign to the inode
+ * @Returns:   0 on success, -ve errno on failure
+ *
+ * inode_newsize_ok will check filesystem limits and ulimits to check that the
+ * new inode size is within limits. inode_newsize_ok will also send SIGXFSZ
+ * when necessary. Caller must not proceed with inode size change if failure is
+ * returned. @inode must be a file (not directory), with appropriate
+ * permissions to allow truncate (inode_newsize_ok does NOT check these
+ * conditions).
+ *
+ * inode_newsize_ok must be called with i_mutex held.
+ */
+int inode_newsize_ok(const struct inode *inode, loff_t offset)
+{
+       if (inode->i_size < offset) {
+               unsigned long limit;
+
+               limit = rlimit(RLIMIT_FSIZE);
+               if (limit != RLIM_INFINITY && offset > limit)
+                       goto out_sig;
+               if (offset > inode->i_sb->s_maxbytes)
+                       goto out_big;
+       } else {
+               /*
+                * truncation of in-use swapfiles is disallowed - it would
+                * cause subsequent swapout to scribble on the now-freed
+                * blocks.
+                */
+               if (IS_SWAPFILE(inode))
+                       return -ETXTBSY;
+       }
+
+       return 0;
+out_sig:
+       send_sig(SIGXFSZ, current, 0);
+out_big:
+       return -EFBIG;
+}
+EXPORT_SYMBOL(inode_newsize_ok);
+
 int inode_setattr(struct inode * inode, struct iattr * attr)
 {
        unsigned int ia_valid = attr->ia_valid;
@@ -108,6 +149,11 @@ int notify_change(struct dentry * dentry, struct iattr * attr)
        struct timespec now;
        unsigned int ia_valid = attr->ia_valid;
 
+       if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | ATTR_TIMES_SET)) {
+               if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
+                       return -EPERM;
+       }
+
        now = current_fs_time(inode->i_sb);
 
        attr->ia_ctime = now;
@@ -154,24 +200,19 @@ int notify_change(struct dentry * dentry, struct iattr * attr)
        if (!(attr->ia_valid & ~(ATTR_KILL_SUID | ATTR_KILL_SGID)))
                return 0;
 
+       error = security_inode_setattr(dentry, attr);
+       if (error)
+               return error;
+
        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)
-                       error = inode->i_op->setattr(dentry, attr);
+               error = inode->i_op->setattr(dentry, attr);
        } else {
                error = inode_change_ok(inode, attr);
                if (!error)
-                       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))
-                               error = DQUOT_TRANSFER(inode, attr) ? -EDQUOT : 0;
-                       if (!error)
-                               error = inode_setattr(inode, attr);
-               }
+                       error = inode_setattr(inode, attr);
        }
 
        if (ia_valid & ATTR_SIZE)