PERFORCE change 120836 for review

[Roman Divacky]

http://perforce.freebsd.org/chv.cgi?CH=120836

Change 120836 by rdivacky at rdivacky_witten on 2007/06/03 12:22:56

	Switch lstat and stat in linux_fstatat64().
	Call namei() to prevent panic.
	Lock the leaf node in stat syscalls.

Affected files ...

.. //depot/projects/soc2007/rdivacky/linux_at/sys/compat/linux/linux_stats.c#7 edit
.. //depot/projects/soc2007/rdivacky/linux_at/sys/kern/vfs_syscalls.c#10 edit

Differences ...

==== //depot/projects/soc2007/rdivacky/linux_at/sys/compat/linux/linux_stats.c#7 (text+ko) ====

@@ -621,9 +621,9 @@
 		dfd = args->dfd;
 
 	if (args->flag & LINUX_AT_SYMLINK_NOFOLLOW)
+		error = kern_lstatat(td, path, UIO_SYSSPACE, &buf, dfd);
+	else
 		error = kern_statat(td, path, UIO_SYSSPACE, &buf, dfd);
-	else
-		error = kern_lstatat(td, path, UIO_SYSSPACE, &buf, dfd);
 		
 	translate_path_major_minor_at(td, args->pathname, &buf, dfd);
 	if (!error)

==== //depot/projects/soc2007/rdivacky/linux_at/sys/kern/vfs_syscalls.c#10 (text+ko) ====

@@ -2134,13 +2134,10 @@
 kern_stat(struct thread *td, char *path, enum uio_seg pathseg, struct stat *sbp)
 {
 	struct nameidata nd;
-	int error;
 	
 	NDINIT(&nd, LOOKUP,
 	    FOLLOW | LOCKSHARED | LOCKLEAF | MPSAFE | AUDITVNODE1,
 	    pathseg, path, td);
-	if ((error = namei(&nd)) != 0)
-		return (error);
 
 	return kern_common_stat(td, sbp, &nd);
 }
@@ -2164,7 +2161,8 @@
 		}
 	}
 
-	NDINIT_AT(&nd, LOOKUP, FOLLOW | AUDITVNODE1 | MPSAFE, pathseg, path, td, dir_vn);
+	NDINIT_AT(&nd, LOOKUP, FOLLOW | LOCKSHARED | LOCKLEAF | AUDITVNODE1 | 
+		MPSAFE, pathseg, path, td, dir_vn);
 
 	error = kern_common_stat(td, sbp, &nd);
 	if (dirfd != AT_FDCWD)
@@ -2178,6 +2176,8 @@
 	struct stat sb;
 	int error, vfslocked;
 
+	if ((error = namei(nd)) != 0)
+		return (error);
 	vfslocked = NDHASGIANT(nd);
 	error = vn_stat(nd->ni_vp, &sb, td->td_ucred, NOCRED, td);
 	NDFREE(nd, NDF_ONLY_PNBUF);
@@ -2221,13 +2221,10 @@
 kern_lstat(struct thread *td, char *path, enum uio_seg pathseg, struct stat *sbp)
 {
 	struct nameidata nd;
-	int error;
 
 	NDINIT(&nd, LOOKUP,
 	    NOFOLLOW | LOCKLEAF | LOCKSHARED | MPSAFE | AUDITVNODE1,
 	    pathseg, path, td);
-	if ((error = namei(&nd)) != 0)
-		return (error);
 
 	return kern_common_lstat(td, sbp, &nd);
 }
@@ -2251,9 +2248,10 @@
 		}
 	}
 
-	NDINIT_AT(&nd, LOOKUP, NOFOLLOW | AUDITVNODE1 | MPSAFE, pathseg, path, td, dir_vn);
+	NDINIT_AT(&nd, LOOKUP, NOFOLLOW | LOCKLEAF | LOCKSHARED | AUDITVNODE1 | 
+		MPSAFE, pathseg, path, td, dir_vn);
 
-	error = kern_common_stat(td, sbp, &nd);
+	error = kern_common_lstat(td, sbp, &nd);
 	if (dirfd != AT_FDCWD)
 		vrele(dir_vn);
 	return (error);
@@ -2266,6 +2264,8 @@
 	struct stat sb;
 	int error, vfslocked;
 
+	if ((error = namei(nd)) != 0)
+		return (error);
 	vfslocked = NDHASGIANT(nd);
 	vp = nd->ni_vp;
 	error = vn_stat(vp, &sb, td->td_ucred, NOCRED, td);