Date: Wed, 4 Mar 2020 20:41:45 +0000 (UTC) From: Ed Maste <emaste@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r358639 - head/contrib/elftoolchain/readelf Message-ID: <202003042041.024KfjNw010688@repo.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: emaste Date: Wed Mar 4 20:41:45 2020 New Revision: 358639 URL: https://svnweb.freebsd.org/changeset/base/358639 Log: readelf: simplify namesz / descsz checks MFC after: 3 days Sponsored by: The FreeBSD Foundation Modified: head/contrib/elftoolchain/readelf/readelf.c Modified: head/contrib/elftoolchain/readelf/readelf.c ============================================================================== --- head/contrib/elftoolchain/readelf/readelf.c Wed Mar 4 20:30:11 2020 (r358638) +++ head/contrib/elftoolchain/readelf/readelf.c Wed Mar 4 20:41:45 2020 (r358639) @@ -3728,6 +3728,7 @@ dump_notes_content(struct readelf *re, const char *buf { Elf_Note *note; const char *end, *name; + uint32_t namesz, descsz; printf("\nNotes at offset %#010jx with length %#010jx:\n", (uintmax_t) off, (uintmax_t) sz); @@ -3739,13 +3740,16 @@ dump_notes_content(struct readelf *re, const char *buf return; } note = (Elf_Note *)(uintptr_t) buf; - buf += sizeof(Elf_Note); - if (buf + roundup2(note->n_namesz, 4) > end) { - warnx("invalid note header name"); + namesz = roundup2(note->n_namesz, 4); + descsz = roundup2(note->n_descsz, 4); + if (namesz < note->n_namesz || descsz < note->n_descsz || + buf + namesz + descsz > end) { + warnx("invalid note header"); return; } + buf += sizeof(Elf_Note); name = buf; - buf += roundup2(note->n_namesz, 4); + buf += namesz; /* * The name field is required to be nul-terminated, and * n_namesz includes the terminating nul in observed @@ -3763,12 +3767,8 @@ dump_notes_content(struct readelf *re, const char *buf printf(" %-13s %#010jx", name, (uintmax_t) note->n_descsz); printf(" %s\n", note_type(name, re->ehdr.e_type, note->n_type)); - if (buf + roundup2(note->n_descsz, 4) > end) { - warnx("invalid note header desc"); - return; - } dump_notes_data(re, name, note->n_type, buf, note->n_descsz); - buf += roundup2(note->n_descsz, 4); + buf += descsz; } }
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?202003042041.024KfjNw010688>