From: Mark Wielaard Date: Thu, 3 Sep 2020 13:42:32 +0000 (-0400) Subject: libebl: Handle aarch64 bti, pac bits in gnu property note X-Git-Tag: elfutils-0.181~2 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=18d64cd8e7ce0761568631bb40136ca7a154b6e0;p=thirdparty%2Felfutils.git libebl: Handle aarch64 bti, pac bits in gnu property note When building with gcc -mbranch-protection= we might get a gnu property note indicating BTI (Branch Target Identification) and/or PAC (Pointer Authentication Code) is being used. Add a small testcase to show eu-readelf -n now properly lists those bits in the gnu property note. Signed-off-by: Mark Wielaard --- diff --git a/libebl/ChangeLog b/libebl/ChangeLog index e54aa2c90..aa43b31f3 100644 --- a/libebl/ChangeLog +++ b/libebl/ChangeLog @@ -1,3 +1,8 @@ +2020-09-03 Mark Wielaard + + * eblobjnote.c (ebl_object_note): For EM_AARCH64 handle BTI and PAC + in GNU_PROPERTY_AARCH64_FEATURE_1_AND. + 2020-07-19 Mark Wielaard * libebl.h: Only typedef Ebl if _LIBASM_H is undefined. diff --git a/libebl/eblobjnote.c b/libebl/eblobjnote.c index f7ac915c5..37cbc4998 100644 --- a/libebl/eblobjnote.c +++ b/libebl/eblobjnote.c @@ -476,6 +476,73 @@ ebl_object_note (Ebl *ebl, uint32_t namesz, const char *name, uint32_t type, } } } + else if (prop.pr_type >= GNU_PROPERTY_LOPROC + && prop.pr_type <= GNU_PROPERTY_HIPROC + && ehdr.e_machine == EM_AARCH64) + { + printf ("AARCH64 "); + if (prop.pr_type == GNU_PROPERTY_AARCH64_FEATURE_1_AND) + { + printf ("FEATURE_1_AND: "); + + if (prop.pr_datasz == 4) + { + GElf_Word data; + in.d_type = ELF_T_WORD; + out.d_type = ELF_T_WORD; + in.d_size = 4; + out.d_size = 4; + in.d_buf = (void *) desc; + out.d_buf = (void *) &data; + + if (gelf_xlatetom (ebl->elf, &out, &in, + elfident[EI_DATA]) == NULL) + { + printf ("%s\n", elf_errmsg (-1)); + return; + } + printf ("%08" PRIx32 " ", data); + + if ((data & GNU_PROPERTY_AARCH64_FEATURE_1_BTI) + != 0) + { + printf ("BTI"); + data &= ~GNU_PROPERTY_AARCH64_FEATURE_1_BTI; + if (data != 0) + printf (" "); + } + + if ((data & GNU_PROPERTY_AARCH64_FEATURE_1_PAC) + != 0) + { + printf ("PAC"); + data &= ~GNU_PROPERTY_AARCH64_FEATURE_1_PAC; + if (data != 0) + printf (" "); + } + + if (data != 0) + printf ("UNKNOWN"); + } + else + printf ("", + prop.pr_datasz); + + printf ("\n"); + } + else + { + printf ("%#" PRIx32, prop.pr_type); + if (prop.pr_datasz > 0) + { + printf (" data: "); + size_t i; + for (i = 0; i < prop.pr_datasz - 1; i++) + printf ("%02" PRIx8 " ", (uint8_t) desc[i]); + printf ("%02" PRIx8 "\n", (uint8_t) desc[i]); + } + } + } else { if (prop.pr_type >= GNU_PROPERTY_LOPROC diff --git a/tests/ChangeLog b/tests/ChangeLog index 047100b09..61c6cb7c3 100644 --- a/tests/ChangeLog +++ b/tests/ChangeLog @@ -1,3 +1,10 @@ +2020-09-03 Mark Wielaard + + * testfile-gnu-property-note-aarch64.bz2: New file. + * run-readelf-n.sh: Handle testfile-gnu-property-note-aarch64. + * Makefile.am (EXTRA_DIST): Add + testfile-gnu-property-note-aarch64.bz2. + 2020-07-19 Mark Wielaard * asm-tst1.c: Include libebl.h after libasm.h. diff --git a/tests/Makefile.am b/tests/Makefile.am index d30b8218e..939bbb6a5 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -319,6 +319,7 @@ EXTRA_DIST = run-arextract.sh run-arsymtest.sh run-ar.sh \ testfile_gnu_props.64le.o.bz2 \ testfile_gnu_props.32be.o.bz2 \ testfile_gnu_props.64be.o.bz2 \ + testfile-gnu-property-note-aarch64.bz2 \ run-allfcts-multi.sh \ test-offset-loop.bz2 test-offset-loop.alt.bz2 \ run-prelink-addr-test.sh \ diff --git a/tests/run-readelf-n.sh b/tests/run-readelf-n.sh index cc7d7f66a..4c98fd824 100755 --- a/tests/run-readelf-n.sh +++ b/tests/run-readelf-n.sh @@ -226,3 +226,34 @@ Note section [ 4] '.note.gnu.property' of 56 bytes at offset 0x40: GNU 8 GNU_PROPERTY_TYPE_0 NO_COPY_ON_PROTECTION EOF + +# - testfile-gnu-property-note.c +# int +# main () +# { +# return 0; +# } +# +# gcc -mbranch-protection=standard -c testfile-gnu-property-note.c +# gcc -o testfile-gnu-property-note-aarch64 testfile-gnu-property-note.o +# eu-strip --remove-section=.gnu.build.attributes \ +# testfile-gnu-property-note-aarch64 + +testfiles testfile-gnu-property-note-aarch64 +testrun_compare ${abs_top_builddir}/src/readelf -n testfile-gnu-property-note-aarch64 << EOF + +Note section [ 2] '.note.gnu.property' of 32 bytes at offset 0x2c8: + Owner Data size Type + GNU 16 GNU_PROPERTY_TYPE_0 + AARCH64 FEATURE_1_AND: 00000003 BTI PAC + +Note section [ 3] '.note.gnu.build-id' of 36 bytes at offset 0x2e8: + Owner Data size Type + GNU 20 GNU_BUILD_ID + Build ID: af82d6df6f3b396487e3e27a826ca9cbbbecbe5f + +Note section [ 4] '.note.ABI-tag' of 32 bytes at offset 0x30c: + Owner Data size Type + GNU 16 GNU_ABI_TAG + OS: Linux, ABI: 3.7.0 +EOF diff --git a/tests/testfile-gnu-property-note-aarch64.bz2 b/tests/testfile-gnu-property-note-aarch64.bz2 new file mode 100755 index 000000000..2fe37b195 Binary files /dev/null and b/tests/testfile-gnu-property-note-aarch64.bz2 differ