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| author | Dave Hansen <haveblue@us.ibm.com> | 2008-02-15 14:37:46 -0800 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2008-04-19 00:29:24 -0400 |
| commit | 42a74f206b914db13ee1f5ae932dcd91a77c8579 (patch) | |
| tree | 24e3dbe55edaacc750067ab9e01778255a6bff08 /fs/hfsplus | |
| parent | 20ddee2c75339cc095f6191c3115f81da8955e96 (diff) | |
| download | linux-42a74f206b914db13ee1f5ae932dcd91a77c8579.tar.gz linux-42a74f206b914db13ee1f5ae932dcd91a77c8579.tar.bz2 linux-42a74f206b914db13ee1f5ae932dcd91a77c8579.zip | |
[PATCH] r/o bind mounts: elevate write count for ioctls()
Some ioctl()s can cause writes to the filesystem. Take these, and make them
use mnt_want/drop_write() instead.
[AV: updated]
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs/hfsplus')
| -rw-r--r-- | fs/hfsplus/ioctl.c | 40 |
1 files changed, 25 insertions, 15 deletions
diff --git a/fs/hfsplus/ioctl.c b/fs/hfsplus/ioctl.c index b60c0affbec5..f457d2ca51ab 100644 --- a/fs/hfsplus/ioctl.c +++ b/fs/hfsplus/ioctl.c @@ -14,6 +14,7 @@ #include <linux/capability.h> #include <linux/fs.h> +#include <linux/mount.h> #include <linux/sched.h> #include <linux/xattr.h> #include <asm/uaccess.h> @@ -35,25 +36,32 @@ int hfsplus_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, flags |= FS_NODUMP_FL; /* EXT2_NODUMP_FL */ return put_user(flags, (int __user *)arg); case HFSPLUS_IOC_EXT2_SETFLAGS: { - if (IS_RDONLY(inode)) - return -EROFS; - - if (!is_owner_or_cap(inode)) - return -EACCES; - - if (get_user(flags, (int __user *)arg)) - return -EFAULT; - + int err = 0; + err = mnt_want_write(filp->f_path.mnt); + if (err) + return err; + + if (!is_owner_or_cap(inode)) { + err = -EACCES; + goto setflags_out; + } + if (get_user(flags, (int __user *)arg)) { + err = -EFAULT; + goto setflags_out; + } if (flags & (FS_IMMUTABLE_FL|FS_APPEND_FL) || HFSPLUS_I(inode).rootflags & (HFSPLUS_FLG_IMMUTABLE|HFSPLUS_FLG_APPEND)) { - if (!capable(CAP_LINUX_IMMUTABLE)) - return -EPERM; + if (!capable(CAP_LINUX_IMMUTABLE)) { + err = -EPERM; + goto setflags_out; + } } /* don't silently ignore unsupported ext2 flags */ - if (flags & ~(FS_IMMUTABLE_FL|FS_APPEND_FL|FS_NODUMP_FL)) - return -EOPNOTSUPP; - + if (flags & ~(FS_IMMUTABLE_FL|FS_APPEND_FL|FS_NODUMP_FL)) { + err = -EOPNOTSUPP; + goto setflags_out; + } if (flags & FS_IMMUTABLE_FL) { /* EXT2_IMMUTABLE_FL */ inode->i_flags |= S_IMMUTABLE; HFSPLUS_I(inode).rootflags |= HFSPLUS_FLG_IMMUTABLE; @@ -75,7 +83,9 @@ int hfsplus_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, inode->i_ctime = CURRENT_TIME_SEC; mark_inode_dirty(inode); - return 0; +setflags_out: + mnt_drop_write(filp->f_path.mnt); + return err; } default: return -ENOTTY; |