diff options
| -rw-r--r-- | fs/attr.c | 36 |
1 files changed, 28 insertions, 8 deletions
diff --git a/fs/attr.c b/fs/attr.c index 12ffdb6fb63c..d0b4d34878fb 100644 --- a/fs/attr.c +++ b/fs/attr.c @@ -18,6 +18,32 @@ #include <linux/evm.h> #include <linux/ima.h> +static bool chown_ok(const struct inode *inode, kuid_t uid) +{ + if (uid_eq(current_fsuid(), inode->i_uid) && + uid_eq(uid, inode->i_uid)) + return true; + if (capable_wrt_inode_uidgid(inode, CAP_CHOWN)) + return true; + if (uid_eq(inode->i_uid, INVALID_UID) && + ns_capable(inode->i_sb->s_user_ns, CAP_CHOWN)) + return true; + return false; +} + +static bool chgrp_ok(const struct inode *inode, kgid_t gid) +{ + if (uid_eq(current_fsuid(), inode->i_uid) && + (in_group_p(gid) || gid_eq(gid, inode->i_gid))) + return true; + if (capable_wrt_inode_uidgid(inode, CAP_CHOWN)) + return true; + if (gid_eq(inode->i_gid, INVALID_GID) && + ns_capable(inode->i_sb->s_user_ns, CAP_CHOWN)) + return true; + return false; +} + /** * setattr_prepare - check if attribute changes to a dentry are allowed * @dentry: dentry to check @@ -52,17 +78,11 @@ int setattr_prepare(struct dentry *dentry, struct iattr *attr) goto kill_priv; /* Make sure a caller can chown. */ - if ((ia_valid & ATTR_UID) && - (!uid_eq(current_fsuid(), inode->i_uid) || - !uid_eq(attr->ia_uid, inode->i_uid)) && - !capable_wrt_inode_uidgid(inode, CAP_CHOWN)) + if ((ia_valid & ATTR_UID) && !chown_ok(inode, attr->ia_uid)) return -EPERM; /* Make sure caller can chgrp. */ - if ((ia_valid & ATTR_GID) && - (!uid_eq(current_fsuid(), inode->i_uid) || - (!in_group_p(attr->ia_gid) && !gid_eq(attr->ia_gid, inode->i_gid))) && - !capable_wrt_inode_uidgid(inode, CAP_CHOWN)) + if ((ia_valid & ATTR_GID) && !chgrp_ok(inode, attr->ia_gid)) return -EPERM; /* Make sure a caller can chmod. */ |