Merge tag 'v3.8-rc3' into v4l_for_linus

Linux 3.8-rc3

* tag 'v3.8-rc3': (11110 commits)
  Linux 3.8-rc3
  mm: reinstante dropped pmd_trans_splitting() check
  cred: Remove tgcred pointer from struct cred
  drm/ttm: fix fence locking in ttm_buffer_object_transfer
  ARM: clps711x: Fix bad merge of clockevents setup
  ARM: highbank: save and restore L2 cache and GIC on suspend
  ARM: highbank: add a power request clear
  ARM: highbank: fix secondary boot and hotplug
  ARM: highbank: fix typos with hignbank in power request functions
  ARM: dts: fix highbank cpu mpidr values
  ARM: dts: add device_type prop to cpu nodes on Calxeda platforms
  drm/prime: drop reference on imported dma-buf come from gem
  xen/netfront: improve truesize tracking
  ARM: mx5: Fix MX53 flexcan2 clock
  ARM: OMAP2+: am33xx-hwmod: Fix wrongly terminated am33xx_usbss_mpu_irqs array
  sctp: fix Kconfig bug in default cookie hmac selection
  EDAC: Cleanup device deregistering path
  EDAC: Fix EDAC Kconfig menu
  EDAC: Fix kernel panic on module unloading
  ALSA: hda - add mute LED for HP Pavilion 17 (Realtek codec)
  ...

1 files changed, 67 insertions, 32 deletions

diff --git a/fs/open.c b/fs/open.c
index 59071f55bf7..9b33c0cbfac 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -61,33 +61,22 @@ int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
 	return ret;
 }
 
-static long do_sys_truncate(const char __user *pathname, loff_t length)
+long vfs_truncate(struct path *path, loff_t length)
 {
-	struct path path;
 	struct inode *inode;
-	int error;
-
-	error = -EINVAL;
-	if (length < 0)	/* sorry, but loff_t says... */
-		goto out;
+	long error;
 
-	error = user_path(pathname, &path);
-	if (error)
-		goto out;
-	inode = path.dentry->d_inode;
+	inode = path->dentry->d_inode;
 
 	/* For directories it's -EISDIR, for other non-regulars - -EINVAL */
-	error = -EISDIR;
 	if (S_ISDIR(inode->i_mode))
-		goto dput_and_out;
-
-	error = -EINVAL;
+		return -EISDIR;
 	if (!S_ISREG(inode->i_mode))
-		goto dput_and_out;
+		return -EINVAL;
 
-	error = mnt_want_write(path.mnt);
+	error = mnt_want_write(path->mnt);
 	if (error)
-		goto dput_and_out;
+		goto out;
 
 	error = inode_permission(inode, MAY_WRITE);
 	if (error)
@@ -111,19 +100,40 @@ static long do_sys_truncate(const char __user *pathname, loff_t length)
 
 	error = locks_verify_truncate(inode, NULL, length);
 	if (!error)
-		error = security_path_truncate(&path);
+		error = security_path_truncate(path);
 	if (!error)
-		error = do_truncate(path.dentry, length, 0, NULL);
+		error = do_truncate(path->dentry, length, 0, NULL);
 
 put_write_and_out:
 	put_write_access(inode);
 mnt_drop_write_and_out:
-	mnt_drop_write(path.mnt);
-dput_and_out:
-	path_put(&path);
+	mnt_drop_write(path->mnt);
 out:
 	return error;
 }
+EXPORT_SYMBOL_GPL(vfs_truncate);
+
+static long do_sys_truncate(const char __user *pathname, loff_t length)
+{
+	unsigned int lookup_flags = LOOKUP_FOLLOW;
+	struct path path;
+	int error;
+
+	if (length < 0)	/* sorry, but loff_t says... */
+		return -EINVAL;
+
+retry:
+	error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path);
+	if (!error) {
+		error = vfs_truncate(&path, length);
+		path_put(&path);
+	}
+	if (retry_estale(error, lookup_flags)) {
+		lookup_flags |= LOOKUP_REVAL;
+		goto retry;
+	}
+	return error;
+}
 
 SYSCALL_DEFINE2(truncate, const char __user *, path, long, length)
 {
@@ -306,6 +316,7 @@ SYSCALL_DEFINE3(faccessat, int, dfd, const char __user *, filename, int, mode)
 	struct path path;
 	struct inode *inode;
 	int res;
+	unsigned int lookup_flags = LOOKUP_FOLLOW;
 
 	if (mode & ~S_IRWXO)	/* where's F_OK, X_OK, W_OK, R_OK? */
 		return -EINVAL;
@@ -328,8 +339,8 @@ SYSCALL_DEFINE3(faccessat, int, dfd, const char __user *, filename, int, mode)
 	}
 
 	old_cred = override_creds(override_cred);
-
-	res = user_path_at(dfd, filename, LOOKUP_FOLLOW, &path);
+retry:
+	res = user_path_at(dfd, filename, lookup_flags, &path);
 	if (res)
 		goto out;
 
@@ -364,6 +375,10 @@ SYSCALL_DEFINE3(faccessat, int, dfd, const char __user *, filename, int, mode)
 
 out_path_release:
 	path_put(&path);
+	if (retry_estale(res, lookup_flags)) {
+		lookup_flags |= LOOKUP_REVAL;
+		goto retry;
+	}
 out:
 	revert_creds(old_cred);
 	put_cred(override_cred);
@@ -379,8 +394,9 @@ SYSCALL_DEFINE1(chdir, const char __user *, filename)
 {
 	struct path path;
 	int error;
-
-	error = user_path_dir(filename, &path);
+	unsigned int lookup_flags = LOOKUP_FOLLOW | LOOKUP_DIRECTORY;
+retry:
+	error = user_path_at(AT_FDCWD, filename, lookup_flags, &path);
 	if (error)
 		goto out;
 
@@ -392,6 +408,10 @@ SYSCALL_DEFINE1(chdir, const char __user *, filename)
 
 dput_and_out:
 	path_put(&path);
+	if (retry_estale(error, lookup_flags)) {
+		lookup_flags |= LOOKUP_REVAL;
+		goto retry;
+	}
 out:
 	return error;
 }
@@ -425,8 +445,9 @@ SYSCALL_DEFINE1(chroot, const char __user *, filename)
 {
 	struct path path;
 	int error;
-
-	error = user_path_dir(filename, &path);
+	unsigned int lookup_flags = LOOKUP_FOLLOW | LOOKUP_DIRECTORY;
+retry:
+	error = user_path_at(AT_FDCWD, filename, lookup_flags, &path);
 	if (error)
 		goto out;
 
@@ -435,7 +456,7 @@ SYSCALL_DEFINE1(chroot, const char __user *, filename)
 		goto dput_and_out;
 
 	error = -EPERM;
-	if (!capable(CAP_SYS_CHROOT))
+	if (!nsown_capable(CAP_SYS_CHROOT))
 		goto dput_and_out;
 	error = security_path_chroot(&path);
 	if (error)
@@ -445,6 +466,10 @@ SYSCALL_DEFINE1(chroot, const char __user *, filename)
 	error = 0;
 dput_and_out:
 	path_put(&path);
+	if (retry_estale(error, lookup_flags)) {
+		lookup_flags |= LOOKUP_REVAL;
+		goto retry;
+	}
 out:
 	return error;
 }
@@ -489,11 +514,16 @@ SYSCALL_DEFINE3(fchmodat, int, dfd, const char __user *, filename, umode_t, mode
 {
 	struct path path;
 	int error;
-
-	error = user_path_at(dfd, filename, LOOKUP_FOLLOW, &path);
+	unsigned int lookup_flags = LOOKUP_FOLLOW;
+retry:
+	error = user_path_at(dfd, filename, lookup_flags, &path);
 	if (!error) {
 		error = chmod_common(&path, mode);
 		path_put(&path);
+		if (retry_estale(error, lookup_flags)) {
+			lookup_flags |= LOOKUP_REVAL;
+			goto retry;
+		}
 	}
 	return error;
 }
@@ -552,6 +582,7 @@ SYSCALL_DEFINE5(fchownat, int, dfd, const char __user *, filename, uid_t, user,
 	lookup_flags = (flag & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW;
 	if (flag & AT_EMPTY_PATH)
 		lookup_flags |= LOOKUP_EMPTY;
+retry:
 	error = user_path_at(dfd, filename, lookup_flags, &path);
 	if (error)
 		goto out;
@@ -562,6 +593,10 @@ SYSCALL_DEFINE5(fchownat, int, dfd, const char __user *, filename, uid_t, user,
 	mnt_drop_write(path.mnt);
 out_release:
 	path_put(&path);
+	if (retry_estale(error, lookup_flags)) {
+		lookup_flags |= LOOKUP_REVAL;
+		goto retry;
+	}
 out:
 	return error;
 }