Amerigo Wang <amwang@xxxxxxxxxx> writes:
>> static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
>> {
>> const struct cred *cred = current_cred();
>>
>> if (iattr->ia_valid & ATTR_FORCE)
>> return 0;
>>
>> if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
>> ATTR_ATIME_SET | ATTR_MTIME_SET))
>> return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
>>
>> return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
>> }
>>
>> I guess it's assuming the ia_valid doesn't have (ATTR_MODE | ATTR_SIZE),
>> but truncate() already does it, I don't know whether it's ok.
>
> No, here we should only force ATTR_KILL_SUID and/or ATTR_KILL_SGID.
> do_truncate() has ATTR_SIZE and ATTR_FILE.
I guess security module should do,
ia_valid = iattr->ia_valid;
if (!(ia_valid & ATTR_FORCE) && (ia_valid & ATTR_FORCE_MASK)) {
err = dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
if (err)
return err;
ia_valid &= ~ATTR_FORCE_MASK;
}
if (ia_valid & ATTR_NOT_FORCE_MASK)
err = dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
return err;
or something. Because do_truncate() already do (ATTR_MODE | ATTR_SIZE)
without ATTR_FORCE.
Thanks.
--
OGAWA Hirofumi <hirofumi@xxxxxxxxxxxxxxxxxx>
--
To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
