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>
diff --git a/fs/hfsplus/ioctl.c b/fs/hfsplus/ioctl.c
index 0e359c3..906bd3d 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 @@
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 @@
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 @@
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;
}