This implements a non-stdio-based getline() equivalent. getline() is not
in the Android NDK until API 21 (Android 5.0.0), while Chrome builds for
32-bit platforms with API 16 (Android 4.1.0). Although a getline()
declaration could be provided in compat for use with older NDK headers,
it’s desirable to move away from stdio entirely. The C++
DelimitedFileReader interface is also a bit more comfortable to use than
getline().
A getdelim() equivalent is also provided, and is also used in the
Linux/Android ProcessInfo implementation.
Bug: crashpad:30
Test: crashpad_util_test FileLineReader.*:ProcessInfo.*
Change-Id: Ic1664758a87cfe4953ab22bd3ae190761404b22c
Reviewed-on: https://chromium-review.googlesource.com/455998
Reviewed-by: Joshua Peraza <jperaza@chromium.org>
Commit-Queue: Mark Mentovai <mark@chromium.org>
The PTRACE_GETREGSET ptrace() request is not supported on ARM before
Linux 3.5.0. This request was only used to determine the bitness of the
target process. Since 64-bit ARM is only supported as of Linux 3.7.0,
when this request is not supported on 32-bit ARM, 64-bit is also not
supported, and the target process must be a 32-bit process.
Bug: crashpad:30
Test: crashpad_util_test ProcessInfo.*
Change-Id: Ib004d24858f146df898dfa6796926d97e2510541
Reviewed-on: https://chromium-review.googlesource.com/455398
Reviewed-by: Joshua Peraza <jperaza@chromium.org>
Not all libc implementations reliably expose pt_regs from
<sys/ptrace.h>. glibc-2.25/sysdeps/generic/sys/ptrace.h, for example,
does not #include <asm/ptrace.h> (which defines the structure) or
anything else that would #include that file such as <linux/ptrace.h>. On
the other hand, Android 7.1.1 bionic/libc/include/sys/ptrace.h does
#include <linux/ptrace.h>.
It is not viable to #include <asm/ptrace.h> or <linux/ptrace.h>
directly: it would be natural to #include them, sorted, before
<sys/ptrace.h> but this causes problems for glibc’s <sys/ptrace.h>.
Constants like PTRACE_GETREGS and PTRACE_TRACEME are simple macros in
<asm/ptrace.h> and <linux/ptrace.h>, respectively, but are defined in
enums in glibc’s <sys/ptrace.h>, and this doesn’t mix well. It is
possible to #include <asm/ptrace.h> (but not <linux/ptrace.h>) after
<sys/ptrace.h>, but because this involves same-value macro redefinitions
and because it reaches into internal headers, it’s not preferred.
The alternative approach taken here is to use the user_regs structure
from <sys/user.h>, which is reliably defined by both Bionic and glibc,
and has the same layout as the kernel’s pt_regs structure. (All that
matters in this code is the size of the structure.) See Android 7.1.1
bionic/libc/include/sys/user.h,
glibc-2.25/sysdeps/unix/sysv/linux/arm/sys/user.h, and
linux-4.9.15/arch/arm/include/asm/ptrace.h for the various equivalent
definitions.
Take the same approach for 64-bit ARM: use user_regs_struct from
<sys/user.h> in preference to hoping for a C library’s <sys/ptrace.h> to
somehow provide the kernel’s user_pt_regs.
This mirrors the approach already being used for x86 and x86_64, which
use the C library’s <sys/user.h> user_regs_struct.
Bug: crashpad:30
Test: crashpad_util_test ProcessInfo.*
Change-Id: I3067e32c7fa4d6c8f4f2d5b63df141a0f490cd13
Reviewed-on: https://chromium-review.googlesource.com/455558
Reviewed-by: Joshua Peraza <jperaza@chromium.org>
Lazy initialization is particularly beneficial for Is64Bit(), which uses
a different (ptrace()-based) approach than the rest of the class (which
is /proc-based). It is possible for the /proc-based Initialize() to
succeed while ptrace() would fail, as it typically would in the
ProcessInfo.Pid1 test. Because this test does not call Is64Bit(),
permission to ptrace() shouldn’t be necessary, and in fact ptrace()
shouldn’t even be called.
This enables the ProcessInfo.Pid1 test on Android (due to ptrace(), it
was actually failing on any Linux, not just Android). It also enables
the ProcessInfo.Forked test on non-Linux, as the prctl(PR_SET_DUMPABLE)
Linux-ism can be removed from it.
Bug: crashpad:30
Test: crashpad_util_test ProcessInfo.*
Change-Id: Ic883733a6aed7e7de9a0f070a5a3544126c7e976
Reviewed-on: https://chromium-review.googlesource.com/455656
Reviewed-by: Joshua Peraza <jperaza@chromium.org>
Commit-Queue: Mark Mentovai <mark@chromium.org>
The process start time in ticks was being converted to an integer from a
temporary string that had gone out of scope by the time the conversion
was performed.
It was possible for a format error in /proc/pid/stat to go undetected
and result in a buffer overflow.
Bug: crashpad:30
Change-Id: I03566dda797bc1f23543bfffcfdb2c5ffe1eca66
Reviewed-on: https://chromium-review.googlesource.com/455378
Reviewed-by: Joshua Peraza <jperaza@chromium.org>
Commit-Queue: Mark Mentovai <mark@chromium.org>
This configuration uses user_regs_struct, which is declared in
<sys/user.h>.
Bug: crashpad:30
Change-Id: Ibdcc60c6719fc2bad9fbeef116efbe764229e14b
Reviewed-on: https://chromium-review.googlesource.com/455197
Reviewed-by: Joshua Peraza <jperaza@chromium.org>
Commit-Queue: Mark Mentovai <mark@chromium.org>
