Date: Tue, 20 Dec 2016 18:25:41 +0000 (UTC) From: Mark Johnston <markj@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r310332 - head/cddl/contrib/opensolaris/lib/libdtrace/common Message-ID: <201612201825.uBKIPfVD099702@repo.freebsd.org>
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Author: markj Date: Tue Dec 20 18:25:41 2016 New Revision: 310332 URL: https://svnweb.freebsd.org/changeset/base/310332 Log: Avoid modifying the object string table when patching USDT probes. dtrace converts pairs of consecutive underscores in a probe name to dashes. When dtrace -G processes relocations corresponding to USDT probe sites, it performs this conversion on the corresponding symbol names prior to looking up the resulting probe names in the USDT provider definition. However, in so doing it would actually modify the input object's string table, which breaks the string suffix merging done by recent binutils. Because we don't care about the symbol name once the probe site is recorded, just perform the probe lookup using a temporary copy. Reported by: hrs, swills MFC after: 3 weeks Modified: head/cddl/contrib/opensolaris/lib/libdtrace/common/dt_link.c Modified: head/cddl/contrib/opensolaris/lib/libdtrace/common/dt_link.c ============================================================================== --- head/cddl/contrib/opensolaris/lib/libdtrace/common/dt_link.c Tue Dec 20 18:09:59 2016 (r310331) +++ head/cddl/contrib/opensolaris/lib/libdtrace/common/dt_link.c Tue Dec 20 18:25:41 2016 (r310332) @@ -1223,6 +1223,7 @@ process_obj(dtrace_hdl_t *dtp, const cha static const char dt_enabled[] = "enabled"; static const char dt_symprefix[] = "$dtrace"; static const char dt_symfmt[] = "%s%ld.%s"; + char probename[DTRACE_NAMELEN]; int fd, i, ndx, eprobe, mod = 0; Elf *elf = NULL; GElf_Ehdr ehdr; @@ -1576,8 +1577,6 @@ process_obj(dtrace_hdl_t *dtp, const cha bcopy(s, pname, p - s); pname[p - s] = '\0'; - p = strhyphenate(p + 3); /* strlen("___") */ - if (dt_symtab_lookup(data_sym, isym, rela.r_offset, shdr_rel.sh_info, &fsym, (emachine1 == EM_PPC64), elf) != 0) @@ -1628,10 +1627,14 @@ process_obj(dtrace_hdl_t *dtp, const cha "no such provider %s", pname)); } - if ((prp = dt_probe_lookup(pvp, p)) == NULL) { + if (strlcpy(probename, p + 3, sizeof (probename)) >= + sizeof (probename)) return (dt_link_error(dtp, elf, fd, bufs, - "no such probe %s", p)); - } + "invalid probe name %s", probename)); + (void) strhyphenate(probename); + if ((prp = dt_probe_lookup(pvp, probename)) == NULL) + return (dt_link_error(dtp, elf, fd, bufs, + "no such probe %s", probename)); assert(fsym.st_value <= rela.r_offset);
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