From 3bd858ab1c451725c07a805dcb315215dc85b86e Mon Sep 17 00:00:00 2001 From: Satyam Sharma Date: Tue, 17 Jul 2007 15:00:08 +0530 Subject: [PATCH] Introduce is_owner_or_cap() to wrap CAP_FOWNER use with fsuid check Introduce is_owner_or_cap() macro in fs.h, and convert over relevant users to it. This is done because we want to avoid bugs in the future where we check for only effective fsuid of the current task against a file's owning uid, without simultaneously checking for CAP_FOWNER as well, thus violating its semantics. [ XFS uses special macros and structures, and in general looked ... untouchable, so we leave it alone -- but it has been looked over. ] The (current->fsuid != inode->i_uid) check in generic_permission() and exec_permission_lite() is left alone, because those operations are covered by CAP_DAC_OVERRIDE and CAP_DAC_READ_SEARCH. Similarly operations falling under the purview of CAP_CHOWN and CAP_LEASE are also left alone. Signed-off-by: Satyam Sharma Cc: Al Viro Acked-by: Serge E. Hallyn Signed-off-by: Linus Torvalds --- fs/attr.c | 4 ++-- fs/ext2/acl.c | 2 +- fs/ext2/ioctl.c | 4 ++-- fs/ext3/acl.c | 2 +- fs/ext3/ioctl.c | 6 +++--- fs/ext4/acl.c | 2 +- fs/ext4/ioctl.c | 6 +++--- fs/fcntl.c | 2 +- fs/generic_acl.c | 2 +- fs/gfs2/acl.c | 2 +- fs/hfsplus/ioctl.c | 2 +- fs/jffs2/acl.c | 2 +- fs/jfs/ioctl.c | 2 +- fs/jfs/xattr.c | 2 +- fs/namei.c | 2 +- fs/ocfs2/ioctl.c | 2 +- fs/reiserfs/ioctl.c | 5 ++--- fs/reiserfs/xattr_acl.c | 2 +- fs/utimes.c | 2 +- fs/xattr.c | 3 +-- include/linux/fs.h | 4 ++++ security/selinux/hooks.c | 2 +- 22 files changed, 32 insertions(+), 30 deletions(-) diff --git a/fs/attr.c b/fs/attr.c index a0a0c7b07b..f8dfc2269d 100644 --- a/fs/attr.c +++ b/fs/attr.c @@ -42,7 +42,7 @@ int inode_change_ok(struct inode *inode, struct iattr *attr) /* Make sure a caller can chmod. */ if (ia_valid & ATTR_MODE) { - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) goto error; /* Also check the setgid bit! */ if (!in_group_p((ia_valid & ATTR_GID) ? attr->ia_gid : @@ -52,7 +52,7 @@ int inode_change_ok(struct inode *inode, struct iattr *attr) /* Check for setting the inode time. */ if (ia_valid & (ATTR_MTIME_SET | ATTR_ATIME_SET)) { - if (current->fsuid != inode->i_uid && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) goto error; } fine: diff --git a/fs/ext2/acl.c b/fs/ext2/acl.c index 7c420b800c..e58669e1b8 100644 --- a/fs/ext2/acl.c +++ b/fs/ext2/acl.c @@ -464,7 +464,7 @@ ext2_xattr_set_acl(struct inode *inode, int type, const void *value, if (!test_opt(inode->i_sb, POSIX_ACL)) return -EOPNOTSUPP; - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EPERM; if (value) { diff --git a/fs/ext2/ioctl.c b/fs/ext2/ioctl.c index e85c482182..3bcd25422e 100644 --- a/fs/ext2/ioctl.c +++ b/fs/ext2/ioctl.c @@ -36,7 +36,7 @@ int ext2_ioctl (struct inode * inode, struct file * filp, unsigned int cmd, if (IS_RDONLY(inode)) return -EROFS; - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EACCES; if (get_user(flags, (int __user *) arg)) @@ -74,7 +74,7 @@ int ext2_ioctl (struct inode * inode, struct file * filp, unsigned int cmd, case EXT2_IOC_GETVERSION: return put_user(inode->i_generation, (int __user *) arg); case EXT2_IOC_SETVERSION: - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EPERM; if (IS_RDONLY(inode)) return -EROFS; diff --git a/fs/ext3/acl.c b/fs/ext3/acl.c index 1e5038d9a0..d34e996743 100644 --- a/fs/ext3/acl.c +++ b/fs/ext3/acl.c @@ -489,7 +489,7 @@ ext3_xattr_set_acl(struct inode *inode, int type, const void *value, if (!test_opt(inode->i_sb, POSIX_ACL)) return -EOPNOTSUPP; - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EPERM; if (value) { diff --git a/fs/ext3/ioctl.c b/fs/ext3/ioctl.c index 965006dba6..4a2a02c95b 100644 --- a/fs/ext3/ioctl.c +++ b/fs/ext3/ioctl.c @@ -41,7 +41,7 @@ int ext3_ioctl (struct inode * inode, struct file * filp, unsigned int cmd, if (IS_RDONLY(inode)) return -EROFS; - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EACCES; if (get_user(flags, (int __user *) arg)) @@ -122,7 +122,7 @@ flags_err: __u32 generation; int err; - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EPERM; if (IS_RDONLY(inode)) return -EROFS; @@ -181,7 +181,7 @@ flags_err: if (IS_RDONLY(inode)) return -EROFS; - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EACCES; if (get_user(rsv_window_size, (int __user *)arg)) diff --git a/fs/ext4/acl.c b/fs/ext4/acl.c index 9e882546d9..a8bae8cd1d 100644 --- a/fs/ext4/acl.c +++ b/fs/ext4/acl.c @@ -489,7 +489,7 @@ ext4_xattr_set_acl(struct inode *inode, int type, const void *value, if (!test_opt(inode->i_sb, POSIX_ACL)) return -EOPNOTSUPP; - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EPERM; if (value) { diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c index 500567dd53..7b4aa4543c 100644 --- a/fs/ext4/ioctl.c +++ b/fs/ext4/ioctl.c @@ -40,7 +40,7 @@ int ext4_ioctl (struct inode * inode, struct file * filp, unsigned int cmd, if (IS_RDONLY(inode)) return -EROFS; - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EACCES; if (get_user(flags, (int __user *) arg)) @@ -121,7 +121,7 @@ flags_err: __u32 generation; int err; - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EPERM; if (IS_RDONLY(inode)) return -EROFS; @@ -180,7 +180,7 @@ flags_err: if (IS_RDONLY(inode)) return -EROFS; - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EACCES; if (get_user(rsv_window_size, (int __user *)arg)) diff --git a/fs/fcntl.c b/fs/fcntl.c index 8e382a5d51..3f22e9f4f6 100644 --- a/fs/fcntl.c +++ b/fs/fcntl.c @@ -215,7 +215,7 @@ static int setfl(int fd, struct file * filp, unsigned long arg) /* O_NOATIME can only be set by the owner or superuser */ if ((arg & O_NOATIME) && !(filp->f_flags & O_NOATIME)) - if (current->fsuid != inode->i_uid && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EPERM; /* required for strict SunOS emulation */ diff --git a/fs/generic_acl.c b/fs/generic_acl.c index 9ccb789471..995d63b2e7 100644 --- a/fs/generic_acl.c +++ b/fs/generic_acl.c @@ -78,7 +78,7 @@ generic_acl_set(struct inode *inode, struct generic_acl_operations *ops, if (S_ISLNK(inode->i_mode)) return -EOPNOTSUPP; - if (current->fsuid != inode->i_uid && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EPERM; if (value) { acl = posix_acl_from_xattr(value, size); diff --git a/fs/gfs2/acl.c b/fs/gfs2/acl.c index 6e80844367..1047a8c722 100644 --- a/fs/gfs2/acl.c +++ b/fs/gfs2/acl.c @@ -74,7 +74,7 @@ int gfs2_acl_validate_remove(struct gfs2_inode *ip, int access) { if (!GFS2_SB(&ip->i_inode)->sd_args.ar_posix_acl) return -EOPNOTSUPP; - if (current->fsuid != ip->i_inode.i_uid && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(&ip->i_inode)) return -EPERM; if (S_ISLNK(ip->i_inode.i_mode)) return -EOPNOTSUPP; diff --git a/fs/hfsplus/ioctl.c b/fs/hfsplus/ioctl.c index 79fd10402e..b60c0affbe 100644 --- a/fs/hfsplus/ioctl.c +++ b/fs/hfsplus/ioctl.c @@ -38,7 +38,7 @@ int hfsplus_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, if (IS_RDONLY(inode)) return -EROFS; - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EACCES; if (get_user(flags, (int __user *)arg)) diff --git a/fs/jffs2/acl.c b/fs/jffs2/acl.c index a46101ee86..65b3a1b5b8 100644 --- a/fs/jffs2/acl.c +++ b/fs/jffs2/acl.c @@ -435,7 +435,7 @@ static int jffs2_acl_setxattr(struct inode *inode, int type, const void *value, struct posix_acl *acl; int rc; - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EPERM; if (value) { diff --git a/fs/jfs/ioctl.c b/fs/jfs/ioctl.c index fe063af6fd..3c8663bea9 100644 --- a/fs/jfs/ioctl.c +++ b/fs/jfs/ioctl.c @@ -69,7 +69,7 @@ int jfs_ioctl(struct inode * inode, struct file * filp, unsigned int cmd, if (IS_RDONLY(inode)) return -EROFS; - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EACCES; if (get_user(flags, (int __user *) arg)) diff --git a/fs/jfs/xattr.c b/fs/jfs/xattr.c index b2375f0774..9b7f2cdaae 100644 --- a/fs/jfs/xattr.c +++ b/fs/jfs/xattr.c @@ -697,7 +697,7 @@ static int can_set_system_xattr(struct inode *inode, const char *name, struct posix_acl *acl; int rc; - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EPERM; /* diff --git a/fs/namei.c b/fs/namei.c index 5e2d98d10c..defaa47c11 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -1576,7 +1576,7 @@ int may_open(struct nameidata *nd, int acc_mode, int flag) /* O_NOATIME can only be set by the owner or superuser */ if (flag & O_NOATIME) - if (current->fsuid != inode->i_uid && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EPERM; /* diff --git a/fs/ocfs2/ioctl.c b/fs/ocfs2/ioctl.c index bd68c3f2af..87dcece7e1 100644 --- a/fs/ocfs2/ioctl.c +++ b/fs/ocfs2/ioctl.c @@ -63,7 +63,7 @@ static int ocfs2_set_inode_attr(struct inode *inode, unsigned flags, goto bail_unlock; status = -EACCES; - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) goto bail_unlock; if (!S_ISDIR(inode->i_mode)) diff --git a/fs/reiserfs/ioctl.c b/fs/reiserfs/ioctl.c index b484d2913c..11a0fcc2d4 100644 --- a/fs/reiserfs/ioctl.c +++ b/fs/reiserfs/ioctl.c @@ -51,8 +51,7 @@ int reiserfs_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, if (IS_RDONLY(inode)) return -EROFS; - if ((current->fsuid != inode->i_uid) - && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EPERM; if (get_user(flags, (int __user *)arg)) @@ -81,7 +80,7 @@ int reiserfs_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, case REISERFS_IOC_GETVERSION: return put_user(inode->i_generation, (int __user *)arg); case REISERFS_IOC_SETVERSION: - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EPERM; if (IS_RDONLY(inode)) return -EROFS; diff --git a/fs/reiserfs/xattr_acl.c b/fs/reiserfs/xattr_acl.c index 5296a29cc5..b7e4fa4539 100644 --- a/fs/reiserfs/xattr_acl.c +++ b/fs/reiserfs/xattr_acl.c @@ -21,7 +21,7 @@ xattr_set_acl(struct inode *inode, int type, const void *value, size_t size) if (!reiserfs_posixacl(inode->i_sb)) return -EOPNOTSUPP; - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EPERM; if (value) { diff --git a/fs/utimes.c b/fs/utimes.c index 83a7e69e70..682eb63b20 100644 --- a/fs/utimes.c +++ b/fs/utimes.c @@ -106,7 +106,7 @@ long do_utimes(int dfd, char __user *filename, struct timespec *times, int flags if (IS_IMMUTABLE(inode)) goto dput_and_out; - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) { + if (!is_owner_or_cap(inode)) { if (f) { if (!(f->f_mode & FMODE_WRITE)) goto dput_and_out; diff --git a/fs/xattr.c b/fs/xattr.c index 4523aca796..a44fd92cac 100644 --- a/fs/xattr.c +++ b/fs/xattr.c @@ -60,8 +60,7 @@ xattr_permission(struct inode *inode, const char *name, int mask) if (!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode)) return -EPERM; if (S_ISDIR(inode->i_mode) && (inode->i_mode & S_ISVTX) && - (mask & MAY_WRITE) && (current->fsuid != inode->i_uid) && - !capable(CAP_FOWNER)) + (mask & MAY_WRITE) && !is_owner_or_cap(inode)) return -EPERM; } diff --git a/include/linux/fs.h b/include/linux/fs.h index 58ce336d4a..98205f6804 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -284,6 +284,7 @@ extern int dir_notify_enable; #include #include #include +#include #include #include @@ -990,6 +991,9 @@ enum { #define put_fs_excl() atomic_dec(¤t->fs_excl) #define has_fs_excl() atomic_read(¤t->fs_excl) +#define is_owner_or_cap(inode) \ + ((current->fsuid == (inode)->i_uid) || capable(CAP_FOWNER)) + /* not quite ready to be deprecated, but... */ extern void lock_super(struct super_block *); extern void unlock_super(struct super_block *); diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 78c3f98fcd..520b999812 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2318,7 +2318,7 @@ static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT) return -EOPNOTSUPP; - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + if (!is_owner_or_cap(inode)) return -EPERM; AVC_AUDIT_DATA_INIT(&ad,FS); -- 2.39.5