This adds some additional output to native crashes. For example, if
something tried to access a bit of mmap(/dev/zero) memory that had
been mprotect()ed, you might see output like this:
I DEBUG : memory map around addr 4015a00c:
I DEBUG : 40159000-4015a000 /system/lib/libstdc++.so
I DEBUG : 4015a000-40162000 /dev/zero
I DEBUG : b0001000-b0009000 /system/bin/linker
The idea is to see what's in and around the fault address to make it
easier to identify bus errors due to file truncation and segmentation
faults caused by buffer over/underruns.
No output is generated for accesses below 0x1000 (which are likely
NULL pointer dereferences) or for signals that don't set si_addr.
Also, suppress the fault address for signals that don't set si_addr:
I DEBUG : signal 6 (SIGABRT), code 0 (?), fault addr --------
We still print "fault addr" followed by 8 characters for anything
that is parsing the contents. The "address" shown for signals like
SIGABRT was meaningless and possibly confusing.
Bug 5358516
Change-Id: Icae8ef309ea2d89b129f68d30f96b2ca8a69cc6c
The structure user_vfp is incorrectly defined in bionic/libc/kernel/arch-arm/asm/ptrace.h
at the moment, while it should be under bionic/libc/kernel/arch-arm/asm/user.h instead.
Before moving its definition in the corresponding source files, we need to fix its users.
It happens that debuggerd is the only one for now, so fix this by including <linux/user.h>
instead (which will include <asm/user.h> and <asm/ptrace.h>).
Also, make the debug output less chatty by specifying all symbols to be listed
through XLOG2 instead of XLOG.
Change-Id: I16e0fa700945d86efd44ee885a84ad609c0a9b58
This change enables debuggerd to provide backtraces with function
names in tombstone files and log messages. It does this by reading
the image file that the address is found in, and parsing the dynamic
symbol table to try to extract the symbol corresponding to the given
address.
This works best when "-Wl,-export-dynamic" is added to the LDFLAGS
of each library and executable, because this will cause all symbols
to be added to the dynamic symbol table. If this flag is not present,
it will still work, but it will only be able to identify functions
which are part of the external API of the library/executable.
Change-Id: I618baaff9ed9143b7d1a1f302224e9f21d2b0626