linux/scripts
Borislav Petkov 18ff44b189 scripts/decodecode: make faulting insn ptr more robust
It can accidentally happen that the faulting insn (the exact instruction
bytes) is repeated a little further on in the trace.  This causes that
same instruction to be tagged twice, see example below.

What we want to do, however, is to track back from the end of the whole
disassembly so many lines as the slice which starts with the faulting
instruction is long.  This leads us to the actual faulting instruction
and *then* we tag it.

While we're at it, we can drop the sed "g" flag because we address only
this one line.

Also, if we point to an instruction which changes decoding depending on
the slice being objdumped, like a Jcc insn, for example, we do not even
tag it as a faulting instruction because the instruction decode changes
in the second slice but we use that second format as a regex on the
fsrst disassembled buffer and more often than not that instruction
doesn't match.

Again, simply tag the line which is deduced from the original "<>"
marking we've received from the kernel.

This also solves the pathologic issue of multiple tagging like this:

  29:*  0f 0b                   ud2         <-- trapping instruction
  2b:*  0f 0b                   ud2         <-- trapping instruction
  2d:*  0f 0b                   ud2         <-- trapping instruction

Double tagging example:

Code: 34 dd 40 30 ad 81 48 c7 c0 80 f6 00 00 48 8b 3c 30 48 01 c6 b8 ff ff ff ff 48 8d 57 f0 48 39 f7 74 2f 49 8b 4c 24 08 48 8b 47 f0 <48> 39 48 08 75 0e eb 2a 66 90 48 8b 40 f0 48 39 48 08 74 1e 48
All code
========
   0:   34 dd                   xor    $0xdd,%al
   2:   40 30 ad 81 48 c7 c0    xor    %bpl,-0x3f38b77f(%rbp)
   9:   80 f6 00                xor    $0x0,%dh
   c:   00 48 8b                add    %cl,-0x75(%rax)
   f:   3c 30                   cmp    $0x30,%al
  11:   48 01 c6                add    %rax,%rsi
  14:   b8 ff ff ff ff          mov    $0xffffffff,%eax
  19:   48 8d 57 f0             lea    -0x10(%rdi),%rdx
  1d:   48 39 f7                cmp    %rsi,%rdi
  20:   74 2f                   je     0x51
  22:   49 8b 4c 24 08          mov    0x8(%r12),%rcx
  27:   48 8b 47 f0             mov    -0x10(%rdi),%rax
  2b:*  48 39 48 08             cmp    %rcx,0x8(%rax)     <-- trapping instruction
  2f:   75 0e                   jne    0x3f
  31:   eb 2a                   jmp    0x5d
  33:   66 90                   xchg   %ax,%ax
  35:   48 8b 40 f0             mov    -0x10(%rax),%rax
  39:*  48 39 48 08             cmp    %rcx,0x8(%rax)     <-- trapping instruction
  3d:   74 1e                   je     0x5d
  3f:   48                      rex.W

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 15:54:27 -07:00
..
basic treewide: Fix typo in various drivers 2013-01-09 11:43:32 +01:00
coccinelle Merge branch 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild 2013-02-27 12:27:18 -08:00
dtc script: dtc: clean generated files 2012-11-21 15:53:22 +00:00
genksyms genksyms: fix metag symbol prefix on crc symbols 2013-03-02 20:11:13 +00:00
kconfig Merge branch 'kbuild/rc-fixes' into kbuild/kconfig 2013-02-25 21:51:57 +01:00
ksymoops
mod mei: bus: Initial MEI Client bus type implementation 2013-03-29 08:35:47 -07:00
package kbuild: clear KBUILD_SRC when calling 'make' in RPM spec 2013-02-22 10:57:32 +01:00
rt-tester
selinux
tracing
.gitignore X.509: Add simple ASN.1 grammar compiler 2012-10-08 13:50:19 +10:30
Kbuild.include Merge branch 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild 2012-10-08 07:56:10 +09:00
Lindent
Makefile X.509: Add simple ASN.1 grammar compiler 2012-10-08 13:50:19 +10:30
Makefile.asm-generic uapi: Allow automatic generation of uapi/asm/ header files 2012-10-17 12:25:44 +01:00
Makefile.build X.509: Add simple ASN.1 grammar compiler 2012-10-08 13:50:19 +10:30
Makefile.clean
Makefile.fwinst kbuild: Fix accidental revert in commit fe04ddf 2012-10-15 13:01:05 -07:00
Makefile.headersinst kbuild: fix make headers_check with make 3.80 2013-03-05 15:02:57 +01:00
Makefile.help
Makefile.host
Makefile.lib kbuild: limit dtc+cpp include path 2013-02-13 10:12:10 +00:00
Makefile.modbuiltin
Makefile.modinst modules: don't break modules_install on external modules with no key. 2012-11-06 11:52:24 +10:30
Makefile.modpost mod/file2alias: make modalias generation safe for cross compiling 2013-01-24 22:48:04 +01:00
Makefile.modsign MODSIGN: Add modules_sign make target 2012-12-14 13:05:28 +10:30
asn1_compiler.c X.509: Add simple ASN.1 grammar compiler 2012-10-08 13:50:19 +10:30
bin2c.c
bloat-o-meter
bootgraph.pl
checkincludes.pl
checkkconfigsymbols.sh
checkpatch.pl checkpatch: fix stringification macro defect 2013-04-17 16:10:44 -07:00
checkstack.pl scripts/checkstack.pl: Add metag support 2013-03-02 20:09:55 +00:00
checksyscalls.sh checksyscalls: fix "here document" handling 2012-09-25 08:59:21 -07:00
checkversion.pl
cleanfile
cleanpatch
coccicheck coccicheck: Allow to show the executed command line 2013-02-22 14:25:44 +01:00
config scripts/config: Fix wrong "shift" for --keep-case 2012-12-14 14:16:10 +01:00
conmakehash.c
decodecode scripts/decodecode: make faulting insn ptr more robust 2013-04-29 15:54:27 -07:00
depmod.sh depmod: pass -P $CONFIG_SYMBOL_PREFIX 2013-02-22 11:52:31 +01:00
diffconfig
docproc.c
export_report.pl
extract-ikconfig
extract-vmlinux
gcc-goto.sh
gcc-version.sh kbuild: Fix gcc -x syntax 2012-10-03 09:03:24 +02:00
gcc-x86_32-has-stack-protector.sh kbuild: Fix gcc -x syntax 2012-10-03 09:03:24 +02:00
gcc-x86_64-has-stack-protector.sh kbuild: Fix gcc -x syntax 2012-10-03 09:03:24 +02:00
gen_initramfs_list.sh
get_maintainer.pl get_maintainer: allow keywords to match filenames 2013-02-27 19:10:09 -08:00
gfp-translate chmod +x scripts/gfp-translate 2012-06-27 12:44:29 -07:00
headerdep.pl
headers.sh
headers_check.pl
headers_install.pl UAPI: Strip _UAPI prefix on header install no matter the whitespace 2013-01-02 17:36:10 -08:00
kallsyms.c
kernel-doc scripts/kernel-doc: handle struct member __aligned without numbers 2013-02-27 19:10:09 -08:00
link-vmlinux.sh kbuild: Fix reading of .config in link-vmlinux.sh 2013-02-25 16:14:48 +01:00
makelst
markup_oops.pl
mkcompile_h
mkmakefile
mksysmap trivial: typo in comment in mksysmap 2012-07-20 10:36:05 +02:00
mkuboot.sh
mkversion
module-common.lds
namespace.pl
patch-kernel scripts/patch-kernel: digest kernel.org hosted .xz patches 2012-03-30 15:23:36 +02:00
pnmtologo.c scripts/pnmtologo: fix for plain PBM 2012-11-20 11:58:03 +01:00
profile2linkerlist.pl
recordmcount.c metag: ftrace support 2013-03-02 20:09:55 +00:00
recordmcount.h ftrace: Make recordmcount.c handle __fentry__ 2012-08-23 11:24:43 -04:00
recordmcount.pl
setlocalversion kbuild: Unset language specific variables in setlocalversion script 2013-02-22 14:18:30 +01:00
show_delta
sign-file MODSIGN: Add -s <signature> option to sign-file 2013-01-25 16:55:36 +10:30
sortextable.c ARM: 7568/1: Sort exception table at compile time 2012-11-04 10:31:16 +00:00
sortextable.h scripts/sortextable: silence script output 2013-02-14 15:04:41 +01:00
tags.sh Merge branch 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild 2013-02-27 12:27:18 -08:00
unifdef.c
ver_linux
xz_wrap.sh xz: Enable BCJ filters on SPARC and 32-bit x86 2012-04-18 13:13:18 -07:00