From owner-svn-src-all@freebsd.org Sat Mar 26 23:39:54 2016 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 9A23CADE5F5; Sat, 26 Mar 2016 23:39:54 +0000 (UTC) (envelope-from np@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 5B4061DD9; Sat, 26 Mar 2016 23:39:54 +0000 (UTC) (envelope-from np@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id u2QNdrpE084203; Sat, 26 Mar 2016 23:39:53 GMT (envelope-from np@FreeBSD.org) Received: (from np@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id u2QNdrUY084200; Sat, 26 Mar 2016 23:39:53 GMT (envelope-from np@FreeBSD.org) Message-Id: <201603262339.u2QNdrUY084200@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: np set sender to np@FreeBSD.org using -f From: Navdeep Parhar Date: Sat, 26 Mar 2016 23:39:53 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r297298 - in head/sys: dev/netmap kern X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 26 Mar 2016 23:39:54 -0000 Author: np Date: Sat Mar 26 23:39:53 2016 New Revision: 297298 URL: https://svnweb.freebsd.org/changeset/base/297298 Log: Plug leak in m_unshare. m_unshare passes on the source mbuf's flags as-is to m_getcl and this results in a leak if the flags include M_NOFREE. The fix is to clear the bits not listed in M_COPYALL before calling m_getcl. M_RDONLY should probably be filtered out too but that's outside the scope of this fix. Add assertions in the zone_mbuf and zone_pack ctors to catch similar bugs. Update netmap_get_mbuf to not pass M_NOFREE to m_getcl. It's not clear what the original code was trying to do but it's likely incorrect. Updated code is no different functionally but it avoids the newly added assertions. Reviewed by: gnn@ Sponsored by: Chelsio Communications Differential Revision: https://reviews.freebsd.org/D5698 Modified: head/sys/dev/netmap/netmap_generic.c head/sys/kern/kern_mbuf.c head/sys/kern/uipc_mbuf.c Modified: head/sys/dev/netmap/netmap_generic.c ============================================================================== --- head/sys/dev/netmap/netmap_generic.c Sat Mar 26 19:16:53 2016 (r297297) +++ head/sys/dev/netmap/netmap_generic.c Sat Mar 26 23:39:53 2016 (r297298) @@ -129,8 +129,9 @@ static inline struct mbuf * netmap_get_mbuf(int len) { struct mbuf *m; - m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR | M_NOFREE); + m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); if (m) { + m->m_flags |= M_NOFREE; /* XXXNP: Almost certainly incorrect. */ m->m_ext.ext_arg1 = m->m_ext.ext_buf; // XXX save m->m_ext.ext_free = (void *)netmap_default_mbuf_destructor; m->m_ext.ext_type = EXT_EXTREF; Modified: head/sys/kern/kern_mbuf.c ============================================================================== --- head/sys/kern/kern_mbuf.c Sat Mar 26 19:16:53 2016 (r297297) +++ head/sys/kern/kern_mbuf.c Sat Mar 26 23:39:53 2016 (r297298) @@ -424,6 +424,7 @@ mb_ctor_mbuf(void *mem, int size, void * m = (struct mbuf *)mem; flags = args->flags; + MPASS((flags & M_NOFREE) == 0); error = m_init(m, how, type, flags); @@ -572,6 +573,7 @@ mb_ctor_pack(void *mem, int size, void * args = (struct mb_args *)arg; flags = args->flags; type = args->type; + MPASS((flags & M_NOFREE) == 0); #ifdef INVARIANTS trash_ctor(m->m_ext.ext_buf, MCLBYTES, arg, how); Modified: head/sys/kern/uipc_mbuf.c ============================================================================== --- head/sys/kern/uipc_mbuf.c Sat Mar 26 19:16:53 2016 (r297297) +++ head/sys/kern/uipc_mbuf.c Sat Mar 26 23:39:53 2016 (r297298) @@ -1670,7 +1670,7 @@ m_unshare(struct mbuf *m0, int how) * don't know how to break up the non-contiguous memory when * doing DMA. */ - n = m_getcl(how, m->m_type, m->m_flags); + n = m_getcl(how, m->m_type, m->m_flags & M_COPYFLAGS); if (n == NULL) { m_freem(m0); return (NULL); @@ -1700,7 +1700,7 @@ m_unshare(struct mbuf *m0, int how) break; off += cc; - n = m_getcl(how, m->m_type, m->m_flags); + n = m_getcl(how, m->m_type, m->m_flags & M_COPYFLAGS); if (n == NULL) { m_freem(mfirst); m_freem(m0);