[RFC ABRT PATCH v2] Add gdb python plugin which analyzes vulnerability
Jiri Moskovcak
jmoskovc at redhat.com
Thu Jun 13 14:03:24 UTC 2013
On 06/13/2013 03:48 PM, Jiri Moskovcak wrote:
> After a quick glance at the code:
>
> - all the functions taking instance as parameter called "self" and then
> working with it should be methods
- after a bit detailed reading on _is_exploitable() seems to change the
state of the instance and should be fixed to not do so, since it's not a
method
- the other functions which takes the instance and just read it should
have the parameter renamed - "self" is really misleading
--Jirka
>
> --Jirka
>
> On 06/13/2013 02:01 PM, Denys Vlasenko wrote:
>> This is an RFC, please do not commit.
>>
>> Usage:
>> Run abrt-action-analyze-vulnerability in a directory which contains
>> ./coredump file.
>> If crash looks exploitable, the tool creates ./exploitable file.
>> Example such a file:
>>
>> """
>> Likely crash reason: Write to an invalid address
>> Exploitable rating (0-9 scale): 6
>> """
>>
>> This patch adds abrt-action-analyze-vulnerability invocation to
>> "EVENT=post-create analyzer=CCpp".
>>
>> TODO:
>> * improve error detection (e.g. what to do if gdb failed to run?)
>> * suppress stray gdb output
>> * set $SIGNO_OF_THE_COREDUMP to work around non-working
>> $_siginfo.si_signo
>> * decide whether to push for $_signo support in gdb (I have a tested
>> gdb patch)
>> * instruction analyzer is x86 specific now, make it per-arch
>> (how to get arch name???)
>>
>> v2: improved instruction analyzer, added more exploibable cases to
>> detect,
>> added tests
>>
>> Signed-off-by: Denys Vlasenko <dvlasenk at redhat.com>
>> ---
>> abrt.spec.in | 2 +
>> src/plugins/Makefile.am | 10 +-
>> src/plugins/abrt-action-analyze-vulnerability | 9 +
>> src/plugins/abrt-gdb-exploitable | 502
>> +++++++++++++++++++++
>> src/plugins/ccpp_event.conf | 5 +-
>> tests/abrt-exploitable/.gitignore | 10 +
>> tests/abrt-exploitable/Makefile | 67 +++
>> tests/abrt-exploitable/testDivideByZero.c | 10 +
>> tests/abrt-exploitable/testExecuteInvalid.c | 17 +
>> .../abrt-exploitable/testFloatingPointException.c | 10 +
>> tests/abrt-exploitable/testReadNull.c | 12 +
>> tests/abrt-exploitable/testReadRandom.c | 14 +
>> tests/abrt-exploitable/testSignalAbort.c | 10 +
>> tests/abrt-exploitable/testSignalIll.c | 10 +
>> tests/abrt-exploitable/testStackBufferOverflow.c | 23 +
>> tests/abrt-exploitable/testStackRecursion.c | 15 +
>> tests/abrt-exploitable/testWriteRandom.c | 15 +
>> 17 files changed, 738 insertions(+), 3 deletions(-)
>> create mode 100755 src/plugins/abrt-action-analyze-vulnerability
>> create mode 100755 src/plugins/abrt-gdb-exploitable
>> create mode 100644 tests/abrt-exploitable/.gitignore
>> create mode 100644 tests/abrt-exploitable/Makefile
>> create mode 100644 tests/abrt-exploitable/testDivideByZero.c
>> create mode 100644 tests/abrt-exploitable/testExecuteInvalid.c
>> create mode 100644 tests/abrt-exploitable/testFloatingPointException.c
>> create mode 100644 tests/abrt-exploitable/testReadNull.c
>> create mode 100644 tests/abrt-exploitable/testReadRandom.c
>> create mode 100644 tests/abrt-exploitable/testSignalAbort.c
>> create mode 100644 tests/abrt-exploitable/testSignalIll.c
>> create mode 100644 tests/abrt-exploitable/testStackBufferOverflow.c
>> create mode 100644 tests/abrt-exploitable/testStackRecursion.c
>> create mode 100644 tests/abrt-exploitable/testWriteRandom.c
>>
>> diff --git a/abrt.spec.in b/abrt.spec.in
>> index fec5b56..ce5f944 100644
>> --- a/abrt.spec.in
>> +++ b/abrt.spec.in
>> @@ -670,6 +670,7 @@ gtk-update-icon-cache %{_datadir}/icons/hicolor
>> &>/dev/null || :
>> %{_initrddir}/abrt-ccpp
>> %endif
>> %{_libexecdir}/abrt-hook-ccpp
>> +%{_libexecdir}/abrt-gdb-exploitable
>>
>> # attr(6755) ~= SETUID|SETGID
>> %attr(6755, abrt, abrt)
>> %{_libexecdir}/abrt-action-install-debuginfo-to-abrt-cache
>> @@ -677,6 +678,7 @@ gtk-update-icon-cache %{_datadir}/icons/hicolor
>> &>/dev/null || :
>> %{_bindir}/abrt-action-analyze-c
>> %{_bindir}/abrt-action-trim-files
>> %{_bindir}/abrt-action-analyze-core
>> +%{_bindir}/abrt-action-analyze-vulnerability
>> %{_bindir}/abrt-action-install-debuginfo
>> %{_bindir}/abrt-action-generate-backtrace
>> %{_bindir}/abrt-action-generate-core-backtrace
>> diff --git a/src/plugins/Makefile.am b/src/plugins/Makefile.am
>> index 767c045..20e0297 100644
>> --- a/src/plugins/Makefile.am
>> +++ b/src/plugins/Makefile.am
>> @@ -3,6 +3,7 @@
>> bin_SCRIPTS = \
>> abrt-action-install-debuginfo \
>> abrt-action-analyze-core \
>> + abrt-action-analyze-vulnerability \
>> abrt-action-analyze-vmcore \
>> abrt-action-list-dsos \
>> abrt-action-perform-ccpp-analysis \
>> @@ -29,9 +30,12 @@ bin_PROGRAMS += \
>> abrt-bodhi
>> endif
>>
>> -libexec_PROGRAMS = abrt-action-install-debuginfo-to-abrt-cache
>> +libexec_PROGRAMS = \
>> + abrt-action-install-debuginfo-to-abrt-cache
>>
>> -libexec_SCRIPTS = abrt-action-ureport
>> +libexec_SCRIPTS = \
>> + abrt-action-ureport \
>> + abrt-gdb-exploitable
>>
>> #dist_pluginsconf_DATA = Python.conf
>>
>> @@ -68,6 +72,7 @@ PYTHON_FILES = \
>> abrt-action-install-debuginfo.in \
>> abrt-action-list-dsos \
>> abrt-action-analyze-core \
>> + abrt-action-analyze-vulnerability \
>> abrt-action-analyze-vmcore.in \
>> abrt-action-perform-ccpp-analysis.in
>>
>> @@ -84,6 +89,7 @@ EXTRA_DIST = \
>> abrt-action-analyze-vmcore \
>> abrt-action-save-kernel-data \
>> abrt-action-ureport \
>> + abrt-gdb-exploitable \
>> https-utils.h \
>> post_report.xml.in \
>> abrt-action-analyze-ccpp-local
>> diff --git a/src/plugins/abrt-action-analyze-vulnerability
>> b/src/plugins/abrt-action-analyze-vulnerability
>> new file mode 100755
>> index 0000000..f2a410e
>> --- /dev/null
>> +++ b/src/plugins/abrt-action-analyze-vulnerability
>> @@ -0,0 +1,9 @@
>> +#!/bin/sh
>> +
>> +if type gdb >/dev/null 2>&1; then
>> + # gdb is avaliable
>> + gdb --batch \
>> + -ex 'python execfile("/usr/libexec/abrt-gdb-exploitable")' \
>> + -ex 'core-file ./coredump' \
>> + -ex 'abrt-exploitable 5 ./exploitable'
>> +fi
>> diff --git a/src/plugins/abrt-gdb-exploitable
>> b/src/plugins/abrt-gdb-exploitable
>> new file mode 100755
>> index 0000000..4f73e0b
>> --- /dev/null
>> +++ b/src/plugins/abrt-gdb-exploitable
>> @@ -0,0 +1,502 @@
>> +#!/usr/bin/python
>> +# This is a GDB plugin.
>> +# Usage:
>> +# gdb --batch -ex 'python execfile("THIS_FILE")' -ex run -ex
>> abrt-exploitable PROG
>> +# or
>> +# gdb --batch -ex 'python execfile("THIS_FILE")' -ex 'core COREDUMP'
>> -ex abrt-exploitable
>> +
>> +import gdb
>> +import os
>> +import signal
>> +
>> +_writing_instr = {
>> + # insn:N, where N:
>> + # -1: this insn always writes to memory
>> + # -2: writes to memory if any operand is a memory operand
>> + # 2: writes to memory if 2nd (or later) operand is a memory operand
>> + #
>> + # Two-operand insns
>> + "add":2,
>> + "adc":2,
>> + "sub":2,
>> + "sbb":2,
>> + "and":2,
>> + "xor":2,
>> + "or":2,
>> + "xadd":2,
>> + "cmpxchg":2,
>> + # One-operand insns. Can use 1 or -2
>> + "inc":-2,
>> + "dec":-2,
>> + "neg":-2,
>> + "not":-2,
>> + "pop":-2,
>> + # "Set byte on condition". One-operand insns.
>> + "seta":-2,
>> + "setae":-2,
>> + "setb":-2,
>> + "setbe":-2,
>> + "setc":-2,
>> + "sete":-2,
>> + "setg":-2,
>> + "setge":-2,
>> + "setl":-2,
>> + "setle":-2,
>> + "setna":-2,
>> + "setnae":-2,
>> + "setnb":-2,
>> + "setnbe":-2,
>> + "setnc":-2,
>> + "setne":-2,
>> + "setng":-2,
>> + "setnge":-2,
>> + "setnl":-2,
>> + "setnle":-2,
>> + "setno":-2,
>> + "setnp":-2,
>> + "setns":-2,
>> + "setnz":-2,
>> + "seto":-2,
>> + "setp":-2,
>> + "setpe":-2,
>> + "setpo":-2,
>> + "sets":-2,
>> + "setz":-2,
>> + # Shifts.
>> + # sarl $2,(%rcx)
>> + # sarl (%rax) - *implicit* operand (shift count) 1.
>> + # shld 11,%ecx,(%rdi) - *third* operand is r/m.
>> + # Luckily, any memory operand is a destination, can use -2.
>> + "shl":-2,
>> + "shr":-2,
>> + "sal":-2,
>> + "sar":-2,
>> + "rol":-2,
>> + "ror":-2,
>> + "rcl":-2,
>> + "rcr":-2,
>> + "shld":-2,
>> + "shrd":-2,
>> + # Bit tests. Any memory operand is a destination, can use -2.
>> + "bts":-2,
>> + "btr":-2,
>> + "btc":-2,
>> + # One-operand (register pair is another, implicit operand).
>> + "cmpxchg8b":-2,
>> + "cmpxchg16b":-2,
>> +
>> + # Either mem operand indicates write to mem.
>> + "xchg":-2,
>> +
>> + # String store insns.
>> + # Look similar to widening signed move "movs[bwl][wlq]",
>> + # but aliasing doesn't happen since widening move has two siffixes
>> + "movs":-1,
>> + "stos":-1,
>> + # Widening moves never store to mem.
>> + # May look like we need to list them because otherwise they get
>> caught
>> + # by "movXXX", but thankfully their 2nd operand is never a memory
>> reference,
>> + # which "movXXX" wildcard checks.
>> + #"mov[sz][bwl][wlq]":0,
>> +
>> + # One-operand insn.
>> + # These are system insns, but they do NOT cause exception in
>> userspace.
>> + "smsw":-2,
>> + "sgdt":-2,
>> + "sidt":-2,
>> + "sldt":-2,
>> + "str":-2,
>> +
>> + # FPU/SIMD madness follows.
>> +
>> + # FPU store insns. One-operand.
>> + "fsts":-2,
>> + "fstl":-2,
>> + #"fstt" doesn't exist
>> + "fstps":-2,
>> + "fstpl":-2,
>> + "fstpt":-2,
>> + # Saving state. One-operand insns.
>> + "fstcw":-2,
>> + "fnstcw":-2,
>> + "fstsw":-2,
>> + "fnstsw":-2,
>> + "fstenv":-2,
>> + "fnstenv":-2,
>> + "fsave":-2,
>> + "fnsave":-2,
>> + "fxsave":-2,
>> + "xsave":-2,
>> + "xsaveopt":-2,
>> + "fsave64":-2,
>> + "fnsave64":-2,
>> + "fxsave64":-2,
>> + "xsave64":-2,
>> + "xsaveopt64":-2,
>> + "stmxcsr":-2,
>> + "vstmxcsr":-2,
>> + # SIMD store insns.
>> + # Three-operand insns. Any memory operand is a destination.
>> + "vcvtps2ph":-2,
>> + "extractps":-2,
>> + "vextractps":-2,
>> + #[v]extractpd does not exist
>> + "vextractf128":-2,
>> + "vextracti128":-2,
>> + "pextr":-2, # covers pextr[bwq]
>> + "pextrd":-2,
>> + "vpextr":-2,
>> + "vpextrd":-2,
>> + "vmaskmovpd":-2,
>> + "vmaskmovps":-2,
>> + "vpmaskmovd":-2,
>> + "vpmaskmovq":-2,
>> + # These insns have implicit (%edi) dest operand:
>> + "maskmovq":-1, # mmx version
>> + "maskmovdqu":-1,
>> + "vmaskmovdqu":-1,
>> +
>> + # check binutils/gas/testsuite/gas/i386/* for more weird insns
>> + # Instruction Set Reference, A-M and N-Z:
>> + # http://download.intel.com/products/processor/manual/253666.pdf
>> + # http://download.intel.com/products/processor/manual/253667.pdf
>> + # SSE4:
>> + #
>> http://software.intel.com/sites/default/files/m/0/3/c/d/4/18187-d9156103.pdf
>>
>> + # Instruction Set Extensions:
>> + #
>> http://download-software.intel.com/sites/default/files/319433-014.pdf
>> + # Xeon Phi:
>> + #
>> http://download-software.intel.com/sites/default/files/forum/278102/327364001en.pdf
>>
>> +
>> + #"vmovXXX" - special-cased in the code
>> + "mov":2
>> +
>> + # Note: stack-writing instructions are omitted
>> +}
>> +
>> +_pushing_instr = {
>> + "push":-1,
>> + "pusha":-1,
>> + "pushf":-1,
>> + "enter":-1,
>> + "call":-1,
>> + "lcall":-1
>> +}
>> +
>> +_intdiv_instr = {
>> + "div":-1,
>> + "idiv":-1
>> +}
>> +
>> +_jumping_instr = {
>> + "jmp":-1, # indirect jumps/calls with garbage data
>> + "call":-1, # call: also possible that stack is exhausted
>> (infinite recursion)
>> + "ljmp":-1,
>> + "lcall":-1,
>> + # Yes, lret/iret isn't used in normal userspace code,
>> + # but it does work (compile with "gcc -nostartfiles -nostdlib
>> -m32"):
>> + #
>> + #_start: .globl _start
>> + # pushf
>> + # push %cs
>> + # push $next
>> + # iret # lret or ret would work too
>> + #next:
>> + # movl $42, %ebx
>> + # movl $1, %eax
>> + # int $0x80 # exit(42)
>> + #
>> + "iret":-1,
>> + "lret":-1,
>> + "ret":-1
>> +}
>> +
>> +_return_instr = {
>> + "iret":-1,
>> + "lret":-1,
>> + "ret":-1 # stack smashed if we crash on this
>> +}
>> +
>> +def _fetch_insn_from_table(ins, table):
>> + if not ins:
>> + return None
>> + if ins in table.keys():
>> + return table[ins]
>> + # Drop common byte/word/long/quad suffix and try again
>> + if ins[-1] in ("b", "w", "l", "q"):
>> + ins = ins[:-1]
>> + if ins in table.keys():
>> + return table[ins]
>> + return None
>> +
>> +def _instruction_is_writing(self):
>> + operand = _fetch_insn_from_table(self.mnemonic, _writing_instr)
>> + if not operand:
>> + if not self.mnemonic:
>> + return False
>> + # There are far too many SSE store instructions,
>> + # don't want to pollute the table with them.
>> + # Special-case the check for MOVxxx
>> + # and its SIMD cousins VMOVxxx:
>> + if self.mnemonic[:3] != "mov" and self.mnemonic[:4] != "vmov":
>> + return False
>> + operand = 2
>> +
>> + if operand == -1: # no need to check operands, it's a write
>> + return True
>> +
>> + # Memory operands look like this: [%seg:][[-]0xHEXNUM][(%reg[,...])]
>> + # Careful with immediate operands which are $0xHEXNUM
>> + # and FPU register references which are st(N).
>> + if self.operands.startswith("0x") or
>> self.operands.startswith("-0x") or self.operands.startswith("("):
>> + mem_op_pos = 0
>> + else:
>> + mem_op_pos = self.operands.find(",0x")
>> + if mem_op_pos < 0:
>> + mem_op_pos = self.operands.find(",-0x")
>> + if mem_op_pos < 0:
>> + mem_op_pos = self.operands.find(":0x")
>> + if mem_op_pos < 0:
>> + mem_op_pos = self.operands.find(":-0x")
>> + if mem_op_pos < 0:
>> + mem_op_pos = self.operands.find(",(")
>> + if mem_op_pos < 0:
>> + mem_op_pos = self.operands.find(":(")
>> + if mem_op_pos < 0:
>> + return False # no memory operands
>> + mem_op_pos += 1
>> +
>> + if operand == -2: # any mem operand indicates write
>> + return True
>> +
>> + comma = self.operands.find(",")
>> + if mem_op_pos < comma:
>> + # "%cs:0x0(%rax,%rax,1),foo" - 1st operand is memory
>> + # "%cs:0x0(%rax),foo" - 1st operand is memory
>> + memory_operand = 1
>> + elif comma < 0:
>> + # "%cs:0x0(%rax)" - 1st operand is memory
>> + memory_operand = 1
>> + else:
>> + # mem_op_pos is after comma
>> + # "foo,%cs:0x0(%rax,%rax,1)" - 2nd operand is memory
>> + # (It also can be a third, fourth etc operand)
>> + memory_operand = 2
>> +
>> + if operand == memory_operand:
>> + return True
>> + return False
>> +
>> +def _instruction_is_pushing(self):
>> + if _fetch_insn_from_table(self.mnemonic, _pushing_instr):
>> + return True
>> + return False
>> +
>> +def _instruction_is_division(self):
>> + if _fetch_insn_from_table(self.mnemonic, _intdiv_instr):
>> + return True
>> + return False
>> +
>> +def _instruction_is_jumping(self):
>> + if _fetch_insn_from_table(self.mnemonic, _jumping_instr):
>> + return True
>> + return False
>> +
>> +def _instruction_is_return(self):
>> + if _fetch_insn_from_table(self.mnemonic, _return_instr):
>> + return True
>> + return False
>> +
>> +class _Signal_and_Insn:
>> + pass
>> +
>> +def _get_signal_and_instruction():
>> + si = _Signal_and_Insn()
>> + si.signo = None
>> + try:
>> + sig = gdb.parse_and_eval("$_signo") # ("$_siginfo.si_signo")
>> + # type(sig) = <type 'gdb.Value'>
>> + # sig is 8 (for SIGFPE)
>> + si.signo = int(sig)
>> + except gdb.error:
>> + # Python Exception <class 'gdb.error'> Attempt to extract a
>> component of a value that is not a structure.:
>> + # Possible reasons why $_siginfo doesn't exist:
>> + # program is still running, program exited normally,
>> + # we work with a coredump from an old kernel.
>> + #
>> + # HACK_ALERT: kernels before 3.?.? do not record siginfo in
>> coredumps,
>> + # so $_siginfo isn't present.
>> + # Lets see whether we are running from the abrt and it
>> provided us with signal number
>> + #
>> + try:
>> + si.signo = int(os.environ["SIGNO_OF_THE_COREDUMP"])
>> + except KeyError:
>> + return None
>> +
>> + si.current_instruction = None
>> + si.mnemonic = None
>> + si.operands = ""
>> + try:
>> + # just "disassemble $pc" won't work if $pc doesn't point
>> + # inside a known function
>> + instructions = gdb.execute("disassemble $pc,$pc+32",
>> to_string=True)
>> + # type(instructions) = <type 'str'>
>> + except gdb.error:
>> + # For example, if tracee already exited normally.
>> + # Another observed case is if $pc points to unmapped area.
>> + # Python Exception <class 'gdb.error'> No registers.:
>> + return si
>> +
>> + raw_instructions = instructions
>> + #print instructions
>> + instructions = []
>> + current = None
>> + for line in raw_instructions.split("\n"):
>> + # line can be:
>> + # "Dump of assembler code from 0xAAAA to 0xBBBB:"
>> + # "[=>] 0x00000000004004dc[ <+0>]: push %rbp"
>> + # (" <+0>" part is present when we run on a live process,
>> + # on coredump it is absent)
>> + # "End of assembler dump."
>> + # "" (empty line)
>> + if line.startswith("=>"):
>> + line = line[2:]
>> + current = len(instructions)
>> + line = line.split(":", 1)
>> + if len(line) < 2: # no ":"?
>> + continue
>> + line = line[1] # drop "foo:"
>> + line = line.strip() # drop leading/trailing whitespace
>> + if line:
>> + instructions.append(line)
>> + if current == None:
>> + # not False! we determined that $pc points to a bad address,
>> + # which is an interesting fact.
>> + return si
>> +
>> + si.current_instruction = instructions[current]
>> + # TODO: too simplistic.
>> + # consider this example:
>> + # "data32 data32 data32 nopw %cs:0x0(%rax,%rax,1)"
>> + t = si.current_instruction.split(None,2)
>> + si.mnemonic = t[0]
>> + if len(t) > 1:
>> + si.operands = t[1]
>> + return si
>> +
>> +#Our initial set of testing will use the list Apple included in their
>> +#CrashWrangler announcement:
>> +#
>> +#Exploitable if:
>> +# Crash on write instruction
>> +# Crash executing invalid address
>> +# Crash calling an invalid address
>> +# Crash accessing an uninitialized or freed pointer as
>> indicated by
>> +# using the MallocScribble environment variable
>> +# Illegal instruction exception
>> +# Abort due to -fstack-protector, _FORTIFY_SOURCE, heap
>> corruption
>> +# detected
>> +# Stack trace of crashing thread contains certain functions
>> such as
>> +# malloc, free, szone_error, objc_MsgSend, etc.
>> +
>> +def _is_exploitable(self):
>> + self.exploitable_rating = 3
>> + self.exploitable_desc = ""
>> +
>> + if 0:
>> + pass
>> + # SIGABRT Abort signal from abort(3)
>> + # SIGQUIT Quit from keyboard
>> + # SIGXCPU CPU time limit exceeded
>> + # SIGXFSZ File size limit exceeded
>> + # SIGTRAP Trace/breakpoint trap
>> + # SIGSYS Bad argument to routine (SVr4)
>> + # SIGFPE Floating point exception
>> + # SIGILL Illegal Instruction
>> + # SIGSEGV Invalid memory reference
>> + # SIGBUS Bus error (bad memory access)
>> + elif self.signo == signal.SIGABRT:
>> + self.exploitable_rating = 0
>> + self.exploitable_desc = "ABRT signal (abort() was called?)"
>> + elif self.signo == signal.SIGQUIT:
>> + self.exploitable_rating = 0
>> + self.exploitable_desc = "QUIT signal (Ctrl-\ pressed?)"
>> + elif self.signo == signal.SIGXCPU:
>> + self.exploitable_rating = 0
>> + self.exploitable_desc = "XCPU signal (over CPU time limit)"
>> + elif self.signo == signal.SIGXFSZ:
>> + self.exploitable_rating = 0
>> + self.exploitable_desc = "XFSZ signal (over file size limit)"
>> + elif self.signo == signal.SIGTRAP:
>> + self.exploitable_rating = 0
>> + self.exploitable_desc = "TRAP signal (can be a bug in a
>> debugger/tracer)"
>> + elif self.signo == signal.SIGSYS:
>> + self.exploitable_rating = 1
>> + self.exploitable_desc = "SYS signal (unknown/masked syscall
>> was called?)"
>> +
>> + elif self.signo == signal.SIGFPE:
>> + self.exploitable_rating = 1
>> + self.exploitable_desc = "Arithmetic exception occurred"
>> + if _instruction_is_division(self):
>> + self.exploitable_rating = 0
>> + self.exploitable_desc = "Division by zero occurred"
>> + elif self.signo == signal.SIGILL:
>> + self.exploitable_rating = 5
>> + self.exploitable_desc = "Illegal instruction (jump to a
>> random address?)"
>> +
>> + # TODO: check that sig is SIGSEGV/SIGBUS?
>> +
>> + elif _instruction_is_pushing(self):
>> + self.exploitable_rating = 4
>> + self.exploitable_desc = "Stack overflow"
>> + elif _instruction_is_writing(self):
>> + self.exploitable_rating = 6
>> + self.exploitable_desc = "Write to an invalid address"
>> + elif _instruction_is_return(self):
>> + self.exploitable_rating = 7
>> + self.exploitable_desc = "Subroutine return to an invalid
>> address (corrupted stack?)"
>> + # Note: we check "ret" first, _then_ jumps.
>> + # Corrupted stack is different from corrupted data.
>> + elif _instruction_is_jumping(self):
>> + self.exploitable_rating = 6
>> + self.exploitable_desc = "Jump to an invalid address"
>> + elif not self.current_instruction:
>> + self.exploitable_rating = 6
>> + self.exploitable_desc = "Jump to an invalid address"
>> + elif self.signo == signal.SIGBUS:
>> + self.exploitable_rating = 5
>> + self.exploitable_desc = "Access past the end of mapped file,
>> invalid address, unaligned access, etc"
>> + #elif self.signo = signal.SIGfoo:
>> +
>> +class AbrtExploitable(gdb.Command):
>> + "Analyze a crash to determine exploitability"
>> + def __init__(self):
>> + super(AbrtExploitable, self).__init__(
>> + "abrt-exploitable",
>> + gdb.COMMAND_SUPPORT, # command class
>> + gdb.COMPLETE_NONE, # completion method
>> + False # => it's not a prefix command
>> + )
>> +
>> + # Called when the command is invoked from GDB
>> + def invoke(self, args, from_tty):
>> + si = _get_signal_and_instruction()
>> + #print "w", _instruction_is_writing(self)
>> + f = sys.stdout
>> + min_rating = 0
>> + if args:
>> + args = args.split(None, 1)
>> + min_rating = int(args[0])
>> + if len(args) > 1:
>> + f = open(args[1], 'w')
>> + if not si:
>> + sys.stderr.write("Can't get signal no and do
>> exploitability analysis\n")
>> + return
>> + _is_exploitable(si)
>> + if si.exploitable_desc:
>> + if si.exploitable_rating >= min_rating:
>> + f.write("Likely crash reason: " + si.exploitable_desc
>> + "\n")
>> + f.write("Exploitable rating (0-9 scale): " +
>> str(si.exploitable_rating) + "\n")
>> + else:
>> + sys.stderr.write("Exploitability analysis on this crash
>> came up empty\n")
>> +
>> +AbrtExploitable()
>> diff --git a/src/plugins/ccpp_event.conf b/src/plugins/ccpp_event.conf
>> index dfc4908..aa8cdb3 100644
>> --- a/src/plugins/ccpp_event.conf
>> +++ b/src/plugins/ccpp_event.conf
>> @@ -15,10 +15,13 @@ EVENT=post-create analyzer=CCpp
>> exit 1
>> fi
>> # Try generating backtrace, if it fails we can still use
>> - # the UUID generated by abrt-action-analyze-c
>> + # the hash generated by abrt-action-analyze-c
>> ##satyr migration:
>> #satyr abrt-create-core-stacktrace "$DUMP_DIR"
>> abrt-action-generate-core-backtrace
>> + # Run GDB plugin to see if crash looks exploitable
>> + abrt-action-analyze-vulnerability
>> + # Generate hash
>> abrt-action-analyze-c &&
>> abrt-action-list-dsos -m maps -o dso_list &&
>> (
>> diff --git a/tests/abrt-exploitable/.gitignore
>> b/tests/abrt-exploitable/.gitignore
>> new file mode 100644
>> index 0000000..b0c3b29
>> --- /dev/null
>> +++ b/tests/abrt-exploitable/.gitignore
>> @@ -0,0 +1,10 @@
>> +testDivideByZero
>> +testExecuteInvalid
>> +testFloatingPointException
>> +testReadNull
>> +testReadRandom
>> +testSignalAbort
>> +testSignalIll
>> +testStackBufferOverflow
>> +testStackRecursion
>> +testWriteRandom
>> diff --git a/tests/abrt-exploitable/Makefile
>> b/tests/abrt-exploitable/Makefile
>> new file mode 100644
>> index 0000000..fe4078d
>> --- /dev/null
>> +++ b/tests/abrt-exploitable/Makefile
>> @@ -0,0 +1,67 @@
>> +# Copyright (C) 2010, 2011 Red Hat, Inc.
>> +#
>> +# This file is part of ABRT.
>> +#
>> +# This program is free software; you can redistribute it and/or modify
>> +# it under the terms of the GNU General Public License as published by
>> +# the Free Software Foundation; either version 2 of the License, or
>> +# (at your option) any later version.
>> +#
>> +# This program is distributed in the hope that it will be useful,
>> +# but WITHOUT ANY WARRANTY; without even the implied warranty of
>> +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
>> +# GNU General Public License for more details.
>> +#
>> +# You should have received a copy of the GNU General Public License
>> +# along with this program. If not, see <http://www.gnu.org/licenses/>.
>> +
>> +CFLAGS=-g
>> +
>> +TESTS=\
>> + testDivideByZero\
>> + testReadNull\
>> + testStackRecursion\
>> + testReadRandom\
>> + testSignalAbort\
>> + testSignalIll\
>> + testWriteRandom\
>> + testExecuteInvalid\
>> + testStackBufferOverflow\
>> + testFloatingPointException\
>> +
>> +all: $(TESTS)
>> +
>> +clean:
>> + rm -f $(TESTS)
>> +
>> +testlive:
>> + for t in $(TESTS); do \
>> + echo "====="; \
>> + echo "Test: $$t"; \
>> + gdb --batch \
>> + -ex 'python
>> execfile("../../src/plugins/abrt-gdb-exploitable")' \
>> + -ex 'run' \
>> + -ex 'disas $$pc-16,$$pc+16' \
>> + -ex 'abrt-exploitable' \
>> + -ex 'cont' \
>> + -ex 'quit' \
>> + ./$$t; \
>> + done 2>&1 | tee testlive.log
>> +
>> +testcore:
>> + rm ./core* 2>/dev/null; \
>> + ulimit -c unlimited; \
>> + for t in $(TESTS); do \
>> + echo "====="; \
>> + echo "Test: $$t"; \
>> + ./$$t && { echo "No crash???"; continue; }; \
>> + mv core* core || { echo "No corefile???"; continue; }; \
>> + gdb --batch \
>> + -ex 'python
>> execfile("../../src/plugins/abrt-gdb-exploitable")' \
>> + -ex 'core ./core' \
>> + -ex 'disas $$pc-16,$$pc+16' \
>> + -ex 'abrt-exploitable' \
>> + -ex 'quit' \
>> + ; \
>> + rm ./core; \
>> + done 2>&1 | tee testcore.log
>> diff --git a/tests/abrt-exploitable/testDivideByZero.c
>> b/tests/abrt-exploitable/testDivideByZero.c
>> new file mode 100644
>> index 0000000..06d1551
>> --- /dev/null
>> +++ b/tests/abrt-exploitable/testDivideByZero.c
>> @@ -0,0 +1,10 @@
>> +/*
>> + * Test a divide by zero error
>> + * This error is not exploitable
>> + */
>> +
>> +#include <stdio.h>
>> +
>> +int main(int argc, char *argv[]) {
>> + printf("%d\n", 7/0);
>> +}
>> diff --git a/tests/abrt-exploitable/testExecuteInvalid.c
>> b/tests/abrt-exploitable/testExecuteInvalid.c
>> new file mode 100644
>> index 0000000..86ce515
>> --- /dev/null
>> +++ b/tests/abrt-exploitable/testExecuteInvalid.c
>> @@ -0,0 +1,17 @@
>> +/*
>> + * Test a crash attempting to execute an invalid address
>> + * This error is exploitable
>> + */
>> +
>> +#include <stdlib.h>
>> +#include <string.h>
>> +
>> +int (*function_pointer)();
>> +
>> +int main(int argc, char *argv[]) {
>> + char *a;
>> + a = malloc(1024);
>> + a = (size_t)a * 1024; // This should put us well outside the
>> valid memory range
>> + function_pointer = a;
>> + function_pointer();
>> +}
>> diff --git a/tests/abrt-exploitable/testFloatingPointException.c
>> b/tests/abrt-exploitable/testFloatingPointException.c
>> new file mode 100644
>> index 0000000..53e8762
>> --- /dev/null
>> +++ b/tests/abrt-exploitable/testFloatingPointException.c
>> @@ -0,0 +1,10 @@
>> +/*
>> + * Test the illegal instruction signal
>> + * This error is exploitable
>> + */
>> +
>> +#include <signal.h>
>> +
>> +int main(int argc, char *argv[]) {
>> + raise(SIGFPE);
>> +}
>> diff --git a/tests/abrt-exploitable/testReadNull.c
>> b/tests/abrt-exploitable/testReadNull.c
>> new file mode 100644
>> index 0000000..548cf73
>> --- /dev/null
>> +++ b/tests/abrt-exploitable/testReadNull.c
>> @@ -0,0 +1,12 @@
>> +/*
>> + * Test a NULL read
>> + * This error is not exploitable
>> + */
>> +
>> +#include <stdio.h>
>> +
>> +int main(int argc, char *argv[]) {
>> + char *a;
>> + a = 0x0;
>> + puts(a);
>> +}
>> diff --git a/tests/abrt-exploitable/testReadRandom.c
>> b/tests/abrt-exploitable/testReadRandom.c
>> new file mode 100644
>> index 0000000..8493078
>> --- /dev/null
>> +++ b/tests/abrt-exploitable/testReadRandom.c
>> @@ -0,0 +1,14 @@
>> +/*
>> + * Test a crash attempting to read invalid memory
>> + * This error is not exploitable
>> + */
>> +
>> +#include <stdio.h>
>> +#include <stdlib.h>
>> +
>> +int main(int argc, char *argv[]) {
>> + char *a;
>> + a = malloc(1024);
>> + a = (size_t)a * 1024; // This should put us well outside the
>> valid memory range
>> + printf("%s\n", a);
>> +}
>> diff --git a/tests/abrt-exploitable/testSignalAbort.c
>> b/tests/abrt-exploitable/testSignalAbort.c
>> new file mode 100644
>> index 0000000..fc41227
>> --- /dev/null
>> +++ b/tests/abrt-exploitable/testSignalAbort.c
>> @@ -0,0 +1,10 @@
>> +/*
>> + * Test the abort signal
>> + * This error is not exploitable
>> + */
>> +
>> +#include <signal.h>
>> +
>> +int main(int argc, char *argv[]) {
>> + raise(SIGABRT);
>> +}
>> diff --git a/tests/abrt-exploitable/testSignalIll.c
>> b/tests/abrt-exploitable/testSignalIll.c
>> new file mode 100644
>> index 0000000..7783263
>> --- /dev/null
>> +++ b/tests/abrt-exploitable/testSignalIll.c
>> @@ -0,0 +1,10 @@
>> +/*
>> + * Test the illegal instruction signal
>> + * This error is exploitable
>> + */
>> +
>> +#include <signal.h>
>> +
>> +int main(int argc, char *argv[]) {
>> + raise(SIGILL);
>> +}
>> diff --git a/tests/abrt-exploitable/testStackBufferOverflow.c
>> b/tests/abrt-exploitable/testStackBufferOverflow.c
>> new file mode 100644
>> index 0000000..fcbd95f
>> --- /dev/null
>> +++ b/tests/abrt-exploitable/testStackBufferOverflow.c
>> @@ -0,0 +1,23 @@
>> +/*
>> + * Test a stack buffer overflow
>> + * This test could be exploitable (it needs further analysis)
>> + */
>> +
>> +#include <stdio.h>
>> +
>> +int i;
>> +
>> +int my_function() {
>> + char a[2];
>> +
>> + for (i = 0; i < 1024; i++) {
>> + a[i] = 'A';
>> + }
>> + printf("%s\n", a);
>> +}
>> +
>> +int main(int argc, char *argv[]) {
>> + my_function();
>> + my_function();
>> + return 0;
>> +}
>> diff --git a/tests/abrt-exploitable/testStackRecursion.c
>> b/tests/abrt-exploitable/testStackRecursion.c
>> new file mode 100644
>> index 0000000..dddf583
>> --- /dev/null
>> +++ b/tests/abrt-exploitable/testStackRecursion.c
>> @@ -0,0 +1,15 @@
>> +/*
>> + * Test a crash from stack recursion
>> + * This error is not exploitable
>> + */
>> +
>> +#include <stdio.h>
>> +
>> +void my_function() {
>> + char a[1024];
>> + my_function();
>> +}
>> +
>> +int main(int argc, char *argv[]) {
>> + my_function();
>> +}
>> diff --git a/tests/abrt-exploitable/testWriteRandom.c
>> b/tests/abrt-exploitable/testWriteRandom.c
>> new file mode 100644
>> index 0000000..812f94c
>> --- /dev/null
>> +++ b/tests/abrt-exploitable/testWriteRandom.c
>> @@ -0,0 +1,15 @@
>> +/*
>> + * Test a crash attempting to write invalid memory
>> + * This error is exploitable
>> + */
>> +
>> +#include <stdlib.h>
>> +#include <string.h>
>> +
>> +int main(int argc, char *argv[]) {
>> + char *a;
>> + char b[] = "pwnt";
>> + a = malloc(1024);
>> + a = (size_t)a * 1024; // This should put us well outside the
>> valid memory range
>> + strcpy(a, b);
>> +}
>>
>
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