Author: brooks Date: Tue May 2 21:20:27 2017 New Revision: 317707 URL: https://svnweb.freebsd.org/changeset/base/317707
Log: Correct an out-of-bounds read in regcomp when the RE is bad. When passed the invalid regular expression "a**", the error is eventually detected and seterr() is called. It sets p->error appropriatly and p->next and p->end to nuls which is a never used char nuls[10] which is zeros due to .bss initialization. Unfortunatly, p_ere_exp() and p_simp_re() both have fall through cases where they set the error, decrement p->next and access it which means a read from what ever .bss variable comes before nuls. Found with regex_test:repet_multi and CHERI bounds checking. Reviewed by: ngie, pfg, emaste Obtained from: CheriBSD Sponsored by: DARPA, AFRL MFC after: 1 week Differential Revision: https://reviews.freebsd.org/D10541 Modified: head/lib/libc/regex/regcomp.c Modified: head/lib/libc/regex/regcomp.c ============================================================================== --- head/lib/libc/regex/regcomp.c Tue May 2 21:09:07 2017 (r317706) +++ head/lib/libc/regex/regcomp.c Tue May 2 21:20:27 2017 (r317707) @@ -444,6 +444,8 @@ p_ere_exp(struct parse *p) (void)REQUIRE(!MORE() || !isdigit((uch)PEEK()), REG_BADRPT); /* FALLTHROUGH */ default: + if (p->error != 0) + return; p->next--; wc = WGETNEXT(); ordinary(p, wc); @@ -651,6 +653,8 @@ p_simp_re(struct parse *p, (void)REQUIRE(starordinary, REG_BADRPT); /* FALLTHROUGH */ default: + if (p->error != 0) + return(0); /* Definitely not $... */ p->next--; wc = WGETNEXT(); ordinary(p, wc); _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
