Commit graph

30 commits

Author SHA1 Message Date
Christopher Ferris
8ea53fa87e Only one crashing thread should contact debuggerd.
If two or more threads crash at the same time, only let one talk to
debuggerd. It's possible for a race to occur that two threads send
data to debuggerd, the second one will cause errors in debuggerd since
the process will die once debuggerd lets the crashing pid start again.

Bug: 19183955
Change-Id: I17dfce46102117ab4a870f7381bd526488d37fb5
2015-01-28 16:20:26 -08:00
Dmitriy Ivanov
1649e7ee5b Enable -Wold-style-cast warnings for linker
And fix old style casts.

Change-Id: I37e7a3e3fd852528ea76f02d967c7bd8cd5b06c9
2015-01-22 16:33:30 -08:00
Christopher Ferris
151da68100 Contact proper debuggerd when crashing.
Make the request structure match the new structure found in debuggerd
code.

On 64 bit systems, make sure that the 32 bit compiled linker is contacted.

Bug: https://code.google.com/p/android/issues/detail?id=97024
Change-Id: I675b8ff222fcf836b05de4e9b5976ff91ca929bf
2015-01-20 17:22:25 -08:00
Elliott Hughes
0dc39f9952 Fix a couple more cases of missing CLOEXEC.
The debuggerd case can probably never happen, because you're crashing at this
point anyway. The system property one seems possible though.

Change-Id: Idba6a4f1d68587ec5b320d1e25f0b6a987ea32a0
2014-09-22 17:43:09 -07:00
Dmitriy Ivanov
851135bf99 Replace NULL with nullptr
Change-Id: Iad50be617d318ca98883b843229c960ad5b9afa9
2014-08-29 14:13:48 -07:00
Christopher Ferris
052fa3a34c Replace snprintf calls in linker.
When enabling debug malloc, the snprintf calls in the linker fails to
update the buffer.

The problem is that snprintf makes a call to pthread_getspecific that
returns a valid pointer, but the data it points to is zero. This should
never happen and causes the snprintf to stop and do nothing.

Temporarily replace snprintf with a different implementation to work
around this issue.

Bug: 16874447
Bug: 17302493

(cherry pick from commit 172955a4e3)

Change-Id: Idca9d417978403d61debfd0434aaa82fd770f33b
2014-08-27 16:01:57 -07:00
Nick Kralevich
be0e43b776 debuggerd: if PR_GET_DUMPABLE=0, don't ask for dumping
PR_GET_DUMPABLE is used by an application to indicate whether or
not core dumps / PTRACE_ATTACH should work.

Security sensitive applications often set PR_SET_DUMPABLE to 0 to
disable core dumps, to avoid leaking sensitive memory to persistent
storage. Similarly, they also set PR_SET_DUMPABLE to zero to prevent
PTRACE_ATTACH from working, again to avoid leaking the contents
of sensitive memory.

Honor PR_GET_DUMPABLE when connecting to debuggerd. If an application
has said it doesn't want its memory dumped, then we shouldn't
ask debuggerd to dump memory on its behalf.

FORTIFY_SOURCE tests: Modify the fortify_source tests to set
PR_SET_DUMPABLE=0. This reduces the total runtime of
/data/nativetest/bionic-unit-tests/bionic-unit-tests32 from approx
53 seconds to 25 seconds. There's no need to connect to debuggerd
when running these tests.

Bug: 16513137
Change-Id: Idc7857b089f3545758f4d9b436b783d580fb653f
2014-07-23 15:48:49 -07:00
Elliott Hughes
00c855eb3d Rethrow SIGTRAP too.
Bug: 15024256
Change-Id: I0347da9698a6ccd317ce6e6f7916d710d66e0f8a
2014-05-16 17:34:13 -07:00
Elliott Hughes
62e35755eb debugger.cpp should know the names of the signals it catches.
Change-Id: I37908b07739ad465652f143848c52bc1ef19e421
2014-05-16 16:59:54 -07:00
Elliott Hughes
1728b23965 Switch to g_ for globals.
That's what the Google style guide recommends, and we're starting
to get a mix.

Change-Id: Ib0c53a890bb5deed5c679e887541a715faea91fc
2014-05-14 10:02:03 -07:00
Elliott Hughes
b7e289ed02 Pass si_code through to debuggerd.
Because we re-raise various signals, we corrupt the si_code that debuggerd
sees when it ptraces our siginfo. One possible solution (shown here) is to
pass the original si_code value in the message we send to debuggerd.

Change-Id: I76f9aa2c0442e5cab611d132532409e700383907
2014-04-25 20:00:45 -07:00
Elliott Hughes
17e6a98b48 Make libc signal handler output more like debuggerd.
This has been annoying me for a while, because it's often quite misleading.

Today, for example, I saw:

  Fatal signal 13 (SIGPIPE) at 0x6573 (code=0), thread 25971 (top)

where the apparent address is actually the pid of the signal source (in this
case the kernel on behalf of the thread itself).

This patch isn't as fancy as strace, but it at least means we never say
anything misleading. We could decode the si_code field like strace and
debuggerd, but I'm reluctant to do that without some way to share the code
between at least bionic and debuggerd.

Examples after:

  Fatal signal 13 (SIGPIPE), code 0 in tid 9157 (top)
  Fatal signal 11 (SIGSEGV), code 1, fault addr 0x0 in tid 9142 (crasher64)
  Fatal signal 6 (SIGABRT), code -6 in tid 9132 (crasher64)

(Note that the code still shows as 0 for SIGPIPE in the signal handler itself
but as -6 (SI_TKILL) in debuggerd; this is actually correct --- debuggerd is
showing the re-raised signal sent at the end of the signal handler that
initially showed the correct code 0.)

Change-Id: I71cad4ab61f422a4f6687a60ac770371790278e0
2014-04-18 17:54:51 -07:00
Elliott Hughes
62e9c76ee8 Clean up debugger.cpp slightly.
In particular, don't do weird things with 'int tid'.

Change-Id: I0fd9158a452967163508ada8987de9494ad5f9af
2014-01-31 17:27:00 -08:00
Elliott Hughes
f858bd1c6e LP64 binaries should talk to debuggerd64.
Change-Id: I7eb30f9d04f80b6b45d3148757970d3f1117493c
2014-01-31 16:56:39 -08:00
Marcus Oakland
e365f9d654 AArch64: Linker64 support for AArch64
Addition of support for AArch64 in the linker64 target.

Change-Id: I8dfd9711278f6706063e91f626b6007ea7a3dd6e
Signed-off-by: Marcus Oakland <marcus.oakland@arm.com>
2013-12-17 15:02:43 -08:00
Elliott Hughes
4eeb1f12a8 Clean up linker architecture macros.
We don't need our own architecture macros; the standard ones will do.

This patch also fixes some __x86_64__ tests to be USE_RELA tests instead,
because they're not actually x86_64-specific.

I've cleaned up architecture-specific code slightly so where possible
all the code corresponding to a particular architecture is together.

This patch also fixes a bug in LP64 DT_PLTGOT handling, which should be
an error rather than falling through into DT_DEBUG! There was another #ifdef
bug where we'd only report unexpected DT_ entries on MIPS.

Change-Id: Id1d04e372611f641c1aa278a18e379f28af9eaf5
2013-10-28 11:02:49 -07:00
Elliott Hughes
c7e9b23317 Fix sigaction(3) for 64-bit.
Also clean up <signal.h> and revert the hacks that were necessary
for 64-bit in linker/debugger.cpp until now.

Change-Id: I3b0554ca8a49ee1c97cda086ce2c1954ebc11892
2013-10-17 11:36:55 -07:00
Elliott Hughes
c00f2cb587 x86_64 linker.
Based on I8dc3e2cb596f75dc58ae82e4dc58f8c177dd3323 by
Pavel Chupin <pavel.v.chupin@intel.com>.

Change-Id: Icd582d277cbe273477b450f2848343d72c86ec9f
2013-10-08 09:57:01 -07:00
Elliott Hughes
c620059479 Remove 32-bit assumptions from the ELF code.
Change-Id: I2c1f3d34c33685799aade8866eec44479ff9f963
2013-09-30 18:43:46 -07:00
Elliott Hughes
84114c8dd5 Improve stack overflow diagnostics (take 2).
This reverts commits eb1b07469f and
d14dc3b87f, and fixes the bug where
we were calling mmap (which might cause errno to be set) before
__set_tls (which is required to implement errno).

Bug: 8557703
Change-Id: I2c36d00240c56e156e1bb430d8c22a73a068b70c
2013-07-17 13:33:19 -07:00
Guang Zhu
d14dc3b87f Revert "Improve stack overflow diagnostics."
This reverts commit aa754dca90.

Change-Id: Ifa76eee31f7f44075eb3a48554315b2693062f44
2013-07-17 03:17:05 +00:00
Elliott Hughes
aa754dca90 Improve stack overflow diagnostics.
We notify debuggerd of problems by installing signal handlers. That's
fine except for when the signal is caused by us running off the end of
a thread's stack and into the guard page.

Bug: 8557703
Change-Id: I1ef65b4bb3bbca7e9a9743056177094921e60ed3
2013-07-16 13:14:24 -07:00
Elliott Hughes
0d787c1fa1 Make abort messages available to debuggerd.
This adds __libc_fatal, cleans up the internal logging code a bit more,
and switches suitable callers over to __libc_fatal. In addition to logging,
__libc_fatal stashes the message somewhere that the debuggerd signal handler
can find it before calling abort.

In the debuggerd signal handler, we pass this address to debuggerd so that
it can come back with ptrace to read the message and present it to the user.

Bug: 8531731
Change-Id: I416ec1da38a8a1b0d0a582ccd7c8aaa681ed4a29
2013-04-05 11:24:19 -07:00
Elliott Hughes
8f2a5a0b40 Clean up internal libc logging.
We only need one logging API, and I prefer the one that does no
allocation and is thus safe to use in any context.

Also use O_CLOEXEC when opening the /dev/log files.

Move everything logging-related into one header file.

Change-Id: Ic1e3ea8e9b910dc29df351bff6c0aa4db26fbb58
2013-03-15 16:12:58 -07:00
Brian Carlstrom
d4ee82dfa3 Minor linker cleanup, primarily to use Elf32_Dyn
Change-Id: Ifa9408e9859c6f79444715bed4808b7c13fdced5
2013-03-05 15:27:21 -08:00
Elliott Hughes
6b8e321e61 Clean up debuggerd-related logging.
Bug: 7291287
Change-Id: Ia7aa386e8b75b8058d7d9e707e11b1da7dc62f00
2013-01-22 14:17:14 -08:00
Elliott Hughes
1e980b6bc8 Fix the duplication in the debugging code.
We had two copies of the backtrace code, and two copies of the
libcorkscrew /proc/pid/maps code. This patch gets us down to one.

We also had hacks so we could log in the malloc debugging code.
This patch pulls the non-allocating "printf" code out of the
dynamic linker so everyone can share.

This patch also makes the leak diagnostics easier to read, and
makes it possible to paste them directly into the 'stack' tool (by
using relative PCs).

This patch also fixes the stdio standard stream leak that was
causing a leak warning every time tf_daemon ran.

Bug: 7291287
Change-Id: I66e4083ac2c5606c8d2737cb45c8ac8a32c7cfe8
2013-01-18 22:20:06 -08:00
Elliott Hughes
61a9ccb41e Make dynamic linker debugging always available.
If you need to build your own linker to get debugging, the debugging
is never available when you need it.

Change-Id: I5ff7e55753459d49a2990f25d9aa155e0b8602e0
2012-11-02 13:46:23 -07:00
Elliott Hughes
d23736e4f2 Keep the dynamic linker's soinfo pools mostly read-only.
We'll need a lot more refactoring of this code before we can reduce
the granularity, but this is a step forward.

Change-Id: I07061720e734b571a8399c1d5b4f2f35cd681307
2012-11-01 16:48:14 -07:00
Elliott Hughes
18a206c81d More dynamic linker cleanup.
I still want to break linker_format out into its own library so we can reuse
it for malloc debugging and so forth. (There are many similar pieces of code
in bionic, but the linker's one seems to be the most complete/functional.)

Change-Id: If3721853d28937c8e821ca1d23cf200e228a409a
2012-10-30 16:35:38 -07:00
Renamed from linker/debugger.c (Browse further)