Date: Fri, 27 Jun 2014 05:04:36 +0000 (UTC) From: Mateusz Guzik <mjg@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r267947 - head/sys/kern Message-ID: <201406270504.s5R54aCa045692@svn.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: mjg Date: Fri Jun 27 05:04:36 2014 New Revision: 267947 URL: http://svnweb.freebsd.org/changeset/base/267947 Log: Check lower bound of cmsg_len. If passed cm->cmsg_len was below cmsghdr size the experssion: datalen = (caddr_t)cm + cm->cmsg_len - (caddr_t)data; would give negative result. However, in practice it would not result in a crash because the kernel would try to obtain garbage fds for given process and would error out with EBADF. PR: 124908 Submitted by: campbell mumble.net (modified a little) MFC after: 1 week Modified: head/sys/kern/uipc_usrreq.c Modified: head/sys/kern/uipc_usrreq.c ============================================================================== --- head/sys/kern/uipc_usrreq.c Fri Jun 27 04:17:05 2014 (r267946) +++ head/sys/kern/uipc_usrreq.c Fri Jun 27 05:04:36 2014 (r267947) @@ -1859,7 +1859,7 @@ unp_internalize(struct mbuf **controlp, *controlp = NULL; while (cm != NULL) { if (sizeof(*cm) > clen || cm->cmsg_level != SOL_SOCKET - || cm->cmsg_len > clen) { + || cm->cmsg_len > clen || cm->cmsg_len < sizeof(*cm)) { error = EINVAL; goto out; }
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201406270504.s5R54aCa045692>