X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=fs%2Fattr.c;h=0815e93bb487e0651619d942b6bd78d7fe6a2e89;hb=57f87869f073929f8e8b3c73748aabb0cece19aa;hp=966b73e25f82e06f69ad0eca22a3f6fe268c4cd0;hpb=6de0ec00ba8db84d7c452e65e502989455ecb6ea;p=safe%2Fjmp%2Flinux-2.6

diff --git a/fs/attr.c b/fs/attr.c
index 966b73e..0815e93 100644
--- 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)