hfsplus: protect setflags using i_mutex

Use i_mutex for protecting against concurrent setflags ioctls like in
other filesystems and get rid of the BKL in hfsplus_ioctl.

Signed-off-by: Christoph Hellwig <hch@tuxera.com>

1 files changed, 8 insertions, 7 deletions

diff --git a/fs/hfsplus/ioctl.c b/fs/hfsplus/ioctl.c
index 0e359c3b55ee..906bd3dd3145 100644
--- a/fs/hfsplus/ioctl.c
+++ b/fs/hfsplus/ioctl.c
@@ -17,7 +17,6 @@
 #include <linux/mount.h>
 #include <linux/sched.h>
 #include <linux/xattr.h>
-#include <linux/smp_lock.h>
 #include <asm/uaccess.h>
 #include "hfsplus_fs.h"
 
@@ -42,10 +41,9 @@ static int hfsplus_ioctl_setflags(struct file *file, int __user *user_flags)
         unsigned int flags;
         int err = 0;
 
-        lock_kernel();
         err = mnt_want_write(file->f_path.mnt);
         if (err)
-                goto out_unlock_kernel;
+                goto out;
 
         if (!is_owner_or_cap(inode)) {
                 err = -EACCES;
@@ -57,18 +55,20 @@ static int hfsplus_ioctl_setflags(struct file *file, int __user *user_flags)
                 goto out_drop_write;
         }
 
+        mutex_lock(&inode->i_mutex);
+
         if (flags & (FS_IMMUTABLE_FL|FS_APPEND_FL) ||
             HFSPLUS_I(inode).rootflags & (HFSPLUS_FLG_IMMUTABLE|HFSPLUS_FLG_APPEND)) {
                 if (!capable(CAP_LINUX_IMMUTABLE)) {
                         err = -EPERM;
-                        goto out_drop_write;
+                        goto out_unlock_inode;
                 }
         }
 
         /* don't silently ignore unsupported ext2 flags */
         if (flags & ~(FS_IMMUTABLE_FL|FS_APPEND_FL|FS_NODUMP_FL)) {
                 err = -EOPNOTSUPP;
-                goto out_drop_write;
+                goto out_unlock_inode;
         }
         if (flags & FS_IMMUTABLE_FL) {
                 inode->i_flags |= S_IMMUTABLE;
@@ -92,10 +92,11 @@ static int hfsplus_ioctl_setflags(struct file *file, int __user *user_flags)
         inode->i_ctime = CURRENT_TIME_SEC;
         mark_inode_dirty(inode);
 
+out_unlock_inode:
+        mutex_lock(&inode->i_mutex);
 out_drop_write:
         mnt_drop_write(file->f_path.mnt);
-out_unlock_kernel:
-        unlock_kernel();
+out:
         return err;
 }