From: Dmitry V. Levin Date: Wed, 16 Nov 2016 22:49:25 +0000 (+0000) Subject: Check for __mprotect failure in _dl_map_segments [BZ #20831] X-Git-Tag: glibc-2.26~628 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=9ace4692b2fa96c1c92177bb51e5e36680de25ad;p=thirdparty%2Fglibc.git Check for __mprotect failure in _dl_map_segments [BZ #20831] * elf/dl-map-segments.h (_dl_map_segments): Check for failure of __mprotect to change protection on the excess portion to disallow all access. --- diff --git a/ChangeLog b/ChangeLog index b72d52164e8..b7c2baf4356 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,10 @@ +2017-04-09 Dmitry V. Levin + + [BZ #20831] + * elf/dl-map-segments.h (_dl_map_segments): Check for failure + of __mprotect to change protection on the excess portion + to disallow all access. + 2017-04-07 H.J. Lu * sysdeps/i386/fpu/fclrexcpt.c (__feclearexcept): Use diff --git a/elf/dl-map-segments.h b/elf/dl-map-segments.h index 31d6861c8e9..d36f9bd2f69 100644 --- a/elf/dl-map-segments.h +++ b/elf/dl-map-segments.h @@ -64,14 +64,18 @@ _dl_map_segments (struct link_map *l, int fd, l->l_addr = l->l_map_start - c->mapstart; if (has_holes) - /* Change protection on the excess portion to disallow all access; - the portions we do not remap later will be inaccessible as if - unallocated. Then jump into the normal segment-mapping loop to - handle the portion of the segment past the end of the file - mapping. */ - __mprotect ((caddr_t) (l->l_addr + c->mapend), - loadcmds[nloadcmds - 1].mapstart - c->mapend, - PROT_NONE); + { + /* Change protection on the excess portion to disallow all access; + the portions we do not remap later will be inaccessible as if + unallocated. Then jump into the normal segment-mapping loop to + handle the portion of the segment past the end of the file + mapping. */ + if (__glibc_unlikely + (__mprotect ((caddr_t) (l->l_addr + c->mapend), + loadcmds[nloadcmds - 1].mapstart - c->mapend, + PROT_NONE) < 0)) + return DL_MAP_SEGMENTS_ERROR_MPROTECT; + } l->l_contiguous = 1;