The thread info expects the struct names as they expect in asm/ptrace.h,
but the header doesn't include that, it includes sys/user.h. Rename the
reg structs to match that header.
Rename the elf_siginfo to _elf_siginfo to avoid conflicting with the one
in the sys/procfs.h. It is only used locally in one place, so we don't
need to update any callers.
Otherwise, drop in aarch64 support into the minidump-2-core file.
BUG=chromium:334368
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1474 4c0a9323-5329-0410-9bdc-e9ce6186880e
When LLVM sees an attempt to dereference a NULL pointer, it will generate
invalid opcodes (undefined behavior) which leads to SIGILL which breaks
this unittest. Upstream's recommendation in this case is to add volatile
markings to get the actual dereference to happen.
This is documented in the blog post under "Dereferencing a NULL Pointer":
http://blog.llvm.org/2011/05/what-every-c-programmer-should-know.html
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1473 4c0a9323-5329-0410-9bdc-e9ce6186880e
When changing a module's start_addr to account for Android packed
relocations, also adjust its size field so that the apparent module
end addr calculated by the breakpad processor does not alter.
Ensures that the mapping entry from a packed library is consistent
with that which an unpacked one would produce.
BUG=499747
R=primiano@chromium.org, rmcilroy@chromium.org
Review URL: https://codereview.chromium.org/1211863002.
Patch from Simon Baldwin <simonb@chromium.org>.
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1465 4c0a9323-5329-0410-9bdc-e9ce6186880e
Shared libraries containing Android packed relocations have a load
bias that differs from the start address in /proc/$$/maps. Current
breakpad assumes that the load bias and mapping start address are
the same.
Fixed by changing the client to detect the presence of Android packed
relocations in the address space of a loaded library, and adjusting the
stored mapping start address of any that are packed so that it contains
the linker's load bias.
For this to work properly, it is important that the non-packed library
is symbolized for breakpad. Either packed or non-packed libraries may
be run on the device; the client detects which has been loaded by the
linker.
BUG=499747
R=primiano@chromium.org, rmcilroy@chromium.org
Review URL: https://codereview.chromium.org/1189823002.
Patch from Simon Baldwin <simonb@chromium.org>.
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1459 4c0a9323-5329-0410-9bdc-e9ce6186880e
This is to add build fingerprint and product name/version to
microdumps. Conversely to what happens in the case of minidumps
with MIME fields, due to the nature of minidumps, extra metadata
cannot be reliably injected after the dump is completed.
This CL adds the plumbing to inject two optional fields plus the
corresponding tests.
BUG=chromium:410294
R=thestig@chromium.org
Review URL: https://codereview.chromium.org/1125153008
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1456 4c0a9323-5329-0410-9bdc-e9ce6186880e
The current code is relying on info->si_pid to figure out whether
the exception handler was triggered by a signal coming from the kernel
(that will re-trigger until the cause that triggered the signal has
been cleared) or from user-space e.g., kill -SIGNAL pid, which will NOT
automatically re-trigger in the next signal handler in the chain.
While the intentions are good (manually re-triggering user-space
signals), the current implementation mistakenly looks at the si_pid
field in siginfo_t, assuming that it is coming from the kernel if
si_pid == 0.
This is wrong. siginfo_t, in fact, is a union and si_pid is meaningful
only for userspace signals. For signals originated by the kernel,
instead, si_pid overlaps with si_addr (the faulting address).
As a matter of facts, the current implementation is mistakenly
re-triggering the signal using tgkill for most of the kernel-space
signals (unless the fault address is exactly 0x0).
This is not completelly correct for the case of SIGSEGV/SIGBUS. The
next handler in the chain will stil see the signal, but the |siginfo|
and the |context| arguments of the handler will be meaningless
(retriggering a signal with tgkill doesn't preserve them).
Therefore, if the next handler in the chain expects those arguments
to be set, it will fail.
Concretelly, this is causing problems to WebView. In some rare
circumstances, the next handler in the chain is a user-space runtime
which does SIGSEGV handling to implement speculative null pointer
managed exceptions (see as an example
http://www.mono-project.com/docs/advanced/runtime/docs/exception-handling/)
The fix herein proposed consists in using the si_code (see SI_FROMUSER
macros) to determine whether a signal is coming form the kernel
(and therefore just re-establish the next signal handler) or from
userspace (and use the tgkill logic).
Repro case:
This issue is visible in Chrome for Android with this simple repro case:
- Add a non-null pointer dereference in the codebase:
*((volatile int*)0xbeef) = 42
Without this change: the next handler (the libc trap) prints:
F/libc ( 595): Fatal signal 11 (SIGSEGV), code 1, fault addr 0x487
where 0x487 is actually the PID of the process (which is wrong).
With this change: the next handler prints:
F/libc ( 595): Fatal signal 11 (SIGSEGV), code 1, fault addr 0xbeef
which is the correct answer.
BUG=chromium:481937
R=mark@chromium.org
Review URL: https://breakpad.appspot.com/6844002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1454 4c0a9323-5329-0410-9bdc-e9ce6186880e
Despite the fact that many places imply that sigaction and rt_sigaction
are essentially the same, rt_sigaction's signature is actually
different-- it takes the size of the kernel's sigset_t as an extra argument.
BUG=473973
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1447 4c0a9323-5329-0410-9bdc-e9ce6186880e
On Android L+, signal and sigaction symbols are provided by libsigchain
that override the system's versions. There is a bug in these functions
where they essentially ignore requests to install SIG_DFL.
Workaround this issue by explicitly performing a syscall to
__NR_rt_sigaction to install SIG_DFL on Android.
BUG=473973
Patch by Chris Hopman <cjhopman@chromium.org>
Review URL: https://breakpad.appspot.com/1804002/
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1438 4c0a9323-5329-0410-9bdc-e9ce6186880e
This is a reland of the previous CL (r1433). r1433 did not achieve what
intended and failed the x86_64 build of Chrome with NDK r10c.
The workaround logic in this CL is identical to r1433, but the #define
magic is applied in a more appropriate proper place this time. Turns
out Breakpad already has an Android compatibility layer, which is
common/android/include. Piggybacking the fix there.
BUG=breakpad:642
R=fdegans@chromium.org, rmcilroy@chromium.org
Review URL: https://breakpad.appspot.com/3794002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1434 4c0a9323-5329-0410-9bdc-e9ce6186880e
r1397 did introduce a workaround to deal with a typo in sys/user.h
in the Android NDK. The typo has been fixed in [1]. However, breakpad
cannot just switch to the fixed version as this would require atomic
rolls of Breakpad and NDK in chromium, which would make reverts hard
to handle.
This change introduces an inelegant yet functional hack which makes
breakpad compatible with both versions of the NDK, with and without
the typo. It can be reverted once Chrome has stably rolled to NDK
r10d.
[1] https://android.googlesource.com/platform/bionic/+/f485547b
BUG=breakpad:642
R=fdegans@chromium.org, rmcilroy@chromium.org
Review URL: https://breakpad.appspot.com/7814002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1433 4c0a9323-5329-0410-9bdc-e9ce6186880e
A recent change in the client-side microdump write (r1404) ended up
introducing a call to new() to instantiate the line buffer that
microdump uses to dump its lines. new/malloc is a luxury we cannot
afford in a compromised context.
This change switches the line buffer to be backed by the dumper
page allocator, which on Linux/Android ends up requesting pages
via mmap.
Also, the microdump write bails out without crashing if the page
allocator failed (crash during severe OOM).
BUG=640
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1432 4c0a9323-5329-0410-9bdc-e9ce6186880e
A computation in the stack unwind algorithm could cause an overflow if a base
pointer read from crashed process is sufficiently close to top of address space.
This causes a memory read that causes the dump thread to crash, resulting in a
failure to generate crash dump. Check fixed to properly detect that this pointer
is greater than actual memory range of current stack.
Patch by Kyle Joswiak <kjoswiak@chromium.org>
Review URL: https://breakpad.appspot.com/3754003/
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1425 4c0a9323-5329-0410-9bdc-e9ce6186880e
When LinuxCoreDumper fails to copy process data from a core file, it
fills the return buffer with a repeated sequence of a special marker.
However, MinidumpWriter doesn't know about that and may incorrectly
interpret the data. In many cases, MinidumpWriter simply copies the
gibberish data to the minidump, which isn't too bad. However, the
gibberish data may cause MinidumpWriter to behave badly in some other
cases. For example, when MinidumpWriter tries to iterate through the
linked list of all loaded DSOs via the r_map field of a r_debug struct,
if the linked list is filed with the special marker, the code keeps
iterating through the same address.
This CL addresses the issue by having LinuxCoreDumper::CopyFromProcess()
returns a Boolean value to indicate if the expected data is found from
the core file. MinidumpWriter can then decide how to handle that.
BUG=chromium:453484
TEST=Run core2md with the test data attached to chromium:453484.
R=mark@chromium.org
Review URL: https://breakpad.appspot.com/4724002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1420 4c0a9323-5329-0410-9bdc-e9ce6186880e
- Filter modules by prot flags (only +x) not extensions. It wouldn't
otherwise catch the case of Chrome mapping the library from the
apk (which is mapped r-x but doesn't end in .so).
- Use compile-time detection of target arch, in order to cope with
multilib OSes, where uname() doesn't reflect the run-time arch.
- Add OS information and CPU arch / count.
- Add support for aarch64.
- Add tests and stackwalk expectations for aarch64.
- Fix a potential overflow bug in the processor.
- Rebaseline the tests using smaller symbols.
- Fix microdump_writer_unittest.cc on 32-bit host.
BUG=chromium:410294
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1407 4c0a9323-5329-0410-9bdc-e9ce6186880e
Microdumps are a very lightweight variant of minidumps. They are meant
to dump a minimal crash report on the system log (logcat on Android),
containing only the state of the crashing thread.
This is to deal with cases where the user has opted out from crash
uploading but we still want to generate meaningful information on the
device to pull a stacktrace for development purposes.
Conversely to conventional stack traces (e.g. the one generated by
Android's debuggerd or Chromium's base::stacktrace) microdumps do NOT
require unwind tables to be present in the target binary. This allows
to save precious binary size (~1.5 MB for Chrome on Arm, ~10 MB on
arm64).
More information and design doc on crbug.com/410294
BUG=chromium:410294
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1398 4c0a9323-5329-0410-9bdc-e9ce6186880e
This change introduces the necessary glue typedefs to deal with the
mismatch introduced by the latest Android NDK (w.r.t. desktop Linux):
- [x86_64] Rename fpregs mxcr_mask -> .mxcsr_mask
- [mips] uc_mcontext.fpregs.fp_r.fp_dregs -> uc_mcontext.fpreg
- [mips] restore the forked user.h
Submitting this on behalf of fdegans@chromium.orgTBR=mark@chromium.org
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1397 4c0a9323-5329-0410-9bdc-e9ce6186880e
This is a refactoring of the logic which determines the
module name and path for a given MappingInfo in minidump_writer.cc.
Such logic, which will be soon shared also with the upcoming
microdump_writer.cc, is simply being moved to linux_dumper.cc,
extracting a GetMappingEffectiveNameAndPath method.
No behavioral change is intended.
BUG=chromium:410294
R=thestig@chromium.org
Review URL: https://breakpad.appspot.com/7734002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1392 4c0a9323-5329-0410-9bdc-e9ce6186880e
This change is a pure refactoring of the common bits of minidump_writer.cc
that will be shared soon with the upcoming microdump_writer.cc.
In particular, this CL is extracting the following classes:
- ThreadInfo: handles the state of the threads in the crashing process.
- RawContextCPU: typedef for arch-specific CPU context structure.
- UContextReader: Fills out a dump RawContextCPU structure from the
ucontext struct provided by the kernel (arch-dependent).
- SeccompUnwinder: cleans out the stack frames of the Seccomp sandbox
on the supported architectures.
- MappingInfo: handles information about mappings
BUG=chromium:410294
R=mmandlis@chromium.org
Review URL: https://breakpad.appspot.com/4684002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1388 4c0a9323-5329-0410-9bdc-e9ce6186880e
When parsing /proc/pid/maps, current code merges adjacent entries that
refer to the same library and where the start of the second is equal to
the end of the first, for example:
40022000-40025000 r-xp 00000000 b3:11 827 /system/lib/liblog.so
40025000-40026000 r--p 00002000 b3:11 827 /system/lib/liblog.so
40026000-40027000 rw-p 00003000 b3:11 827 /system/lib/liblog.so
When the system linker loads a library it first reserves all the address
space required, from the smallest start to the largest end address, using
an anonymous mapping, and then maps loaded segments inside that reservation.
If the loaded segments do not fully occupy the reservation this leaves
gaps, and these gaps prevent merges that should occur from occurring:
40417000-4044a000 r-xp 00000000 b3:11 820 /system/lib/libjpeg.so
> 4044a000-4044b000 ---p 00000000 00:00 0
4044b000-4044c000 r--p 00033000 b3:11 820 /system/lib/libjpeg.so
4044c000-4044d000 rw-p 00034000 b3:11 820 /system/lib/libjpeg.so
Where the segments that follow this gap do not contain executable code
the failure to merge does not affect breakpad operation. However, where
they do then the merge needs to occur. Packing relocations in a large
library splits the executable segment into two, resulting in:
73b0c000-73b21000 r-xp 00000000 b3:19 786460 /data/.../libchrome.2160.0.so
> 73b21000-73d12000 ---p 00000000 00:00 0
73d12000-75a90000 r-xp 00014000 b3:19 786460 /data/.../libchrome.2160.0.so
75a90000-75c0d000 rw-p 01d91000 b3:19 786460 /data/.../libchrome.2160.0.so
Here the mapping at 73d12000-75a90000 must be merged into 73b0c000-73b21000
so that breakpad correctly calculates the base address for text.
This change enables the full merge by also merging anonymous maps which
result from unused reservation, identified as '---p' with offset 0, and
which follow on from an executable mapping, into that executable mapping.
BUG=chromium:394703
R=rmcilroy@chromium.org, thestig@chromium.org
Review URL: https://breakpad.appspot.com/7714003
Patch from Simon Baldwin <simonb@chromium.org>.
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1380 4c0a9323-5329-0410-9bdc-e9ce6186880e
This patch makes two changes to breakpad to enable crash reporting to work correctly when the library is inside another file (an archive):
- Do not filter mappings which map an executable at a non-zero offset.
- If such an executable is mapped look in the ELF information for the
shared object name and use that name in the minidump.
Note this change doesn't care about the archive format and isn't Android
specific (though loading the shared library this way is currently only done on Android).
BUG=390618
R=thestig@chromium.org
Review URL: https://breakpad.appspot.com/7684002
Patch from Anton Carver <anton@chromium.org>.
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1355 4c0a9323-5329-0410-9bdc-e9ce6186880e
__system_property_get has been removed from the Android NDK for 'L' so Breakpad
no longer links. This CL just removes the call in WriteOSInformation because
Chrome already passes the build fingerprint as a crash key called "android_build_fp" in the crash report HTTP POST message.
BUG=394841,393903
R=mark@chromium.org
Review URL: https://breakpad.appspot.com/1694002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1351 4c0a9323-5329-0410-9bdc-e9ce6186880e
This bug manifests itself on Android x64 (in ExceptionHandlerTest::ExternalDumper), but is possible on any platform.
The compiler is unaware of the code which runs in the signal handler which reads this variable. Without volatile the compiler is free to optimise away writes to this variable which it believes are never read.
BUG=381142, 346626
R=thestig@chromium.org
Review URL: https://breakpad.appspot.com/8664002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1343 4c0a9323-5329-0410-9bdc-e9ce6186880e
This is an initial attempt to add Arm64 (aarch64) support to Breakpad for
Linux / Android platforms. This CL adds the Arm64 data structures, but does
not yet implement the Android getcontext support or CPUFillFromThreadInfo /
CPUFillFromUContext.
BUG=354405,335641
R=mark@chromium.org
Review URL: https://breakpad.appspot.com/1354002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1301 4c0a9323-5329-0410-9bdc-e9ce6186880e
