hfsplus: protect setflags using i_mutex (6333816a) · Commits · 戴 / test

fs/hfsplus/ioctl.c

+8 −7

Original line number	Diff line number	Diff line
		@@ -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;
		}