Create a debugger_process_info data structure with the process info pointers.
Similar to r.android.com/1247247 I'll be adding more of them for MTE.
Also, change the protocol between the crasher and crash_dump to make
it easier to add new fields and change the referenced data structures
without needing to worry about versioning. The version number for
static executables is now always 1 (where the protocol will never
change), while the version number for dynamic executables is always
4 (where the protocol can change, because the linker and crash_dump
are version locked).
Bug: 135772972
Change-Id: Ib4696d0544d7c87cb429aaaa15f18c3640059e16
diff --git a/debuggerd/crash_dump.cpp b/debuggerd/crash_dump.cpp
index 6a38145..087ebae 100644
--- a/debuggerd/crash_dump.cpp
+++ b/debuggerd/crash_dump.cpp
@@ -264,15 +264,13 @@
ssize_t expected_size = 0;
switch (crash_info->header.version) {
case 1:
- expected_size = sizeof(CrashInfoHeader) + sizeof(CrashInfoDataV1);
- break;
-
case 2:
- expected_size = sizeof(CrashInfoHeader) + sizeof(CrashInfoDataV2);
+ case 3:
+ expected_size = sizeof(CrashInfoHeader) + sizeof(CrashInfoDataStatic);
break;
- case 3:
- expected_size = sizeof(CrashInfoHeader) + sizeof(CrashInfoDataV3);
+ case 4:
+ expected_size = sizeof(CrashInfoHeader) + sizeof(CrashInfoDataDynamic);
break;
default:
@@ -280,25 +278,25 @@
break;
};
- if (rc != expected_size) {
+ if (rc < expected_size) {
LOG(FATAL) << "read " << rc << " bytes when reading target crash information, expected "
<< expected_size;
}
}
switch (crash_info->header.version) {
- case 3:
- process_info->gwp_asan_state = crash_info->data.v3.gwp_asan_state;
- process_info->gwp_asan_metadata = crash_info->data.v3.gwp_asan_metadata;
- FALLTHROUGH_INTENDED;
- case 2:
- process_info->fdsan_table_address = crash_info->data.v2.fdsan_table_address;
+ case 4:
+ process_info->fdsan_table_address = crash_info->data.d.fdsan_table_address;
+ process_info->gwp_asan_state = crash_info->data.d.gwp_asan_state;
+ process_info->gwp_asan_metadata = crash_info->data.d.gwp_asan_metadata;
FALLTHROUGH_INTENDED;
case 1:
- process_info->abort_msg_address = crash_info->data.v1.abort_msg_address;
- *siginfo = crash_info->data.v1.siginfo;
+ case 2:
+ case 3:
+ process_info->abort_msg_address = crash_info->data.s.abort_msg_address;
+ *siginfo = crash_info->data.s.siginfo;
regs->reset(unwindstack::Regs::CreateFromUcontext(unwindstack::Regs::CurrentArch(),
- &crash_info->data.v1.ucontext));
+ &crash_info->data.s.ucontext));
break;
default:
diff --git a/debuggerd/crasher/crasher.cpp b/debuggerd/crasher/crasher.cpp
index 3041664..a2b13a3 100644
--- a/debuggerd/crasher/crasher.cpp
+++ b/debuggerd/crasher/crasher.cpp
@@ -349,7 +349,7 @@
int main(int argc, char** argv) {
#if defined(STATIC_CRASHER)
debuggerd_callbacks_t callbacks = {
- .get_abort_message = []() {
+ .get_process_info = []() {
static struct {
size_t size;
char msg[32];
@@ -357,7 +357,9 @@
msg.size = strlen("dummy abort message");
memcpy(msg.msg, "dummy abort message", strlen("dummy abort message"));
- return reinterpret_cast<abort_msg_t*>(&msg);
+ return debugger_process_info{
+ .abort_msg = reinterpret_cast<void*>(&msg),
+ };
},
.post_dump = nullptr
};
diff --git a/debuggerd/handler/debuggerd_handler.cpp b/debuggerd/handler/debuggerd_handler.cpp
index 8b4b630..84d2bd0 100644
--- a/debuggerd/handler/debuggerd_handler.cpp
+++ b/debuggerd/handler/debuggerd_handler.cpp
@@ -297,10 +297,7 @@
pid_t pseudothread_tid;
siginfo_t* siginfo;
void* ucontext;
- uintptr_t abort_msg;
- uintptr_t fdsan_table;
- uintptr_t gwp_asan_state;
- uintptr_t gwp_asan_metadata;
+ debugger_process_info process_info;
};
// Logging and contacting debuggerd requires free file descriptors, which we might not have.
@@ -344,25 +341,36 @@
fatal_errno("failed to create pipe");
}
- // ucontext_t is absurdly large on AArch64, so piece it together manually with writev.
- uint32_t version = 3;
- constexpr size_t expected = sizeof(CrashInfoHeader) + sizeof(CrashInfoDataV3);
+ uint32_t version;
+ ssize_t expected;
+ // ucontext_t is absurdly large on AArch64, so piece it together manually with writev.
+ struct iovec iovs[4] = {
+ {.iov_base = &version, .iov_len = sizeof(version)},
+ {.iov_base = thread_info->siginfo, .iov_len = sizeof(siginfo_t)},
+ {.iov_base = thread_info->ucontext, .iov_len = sizeof(ucontext_t)},
+ };
+
+ if (thread_info->process_info.fdsan_table) {
+ // Dynamic executables always use version 4. There is no need to increment the version number if
+ // the format changes, because the sender (linker) and receiver (crash_dump) are version locked.
+ version = 4;
+ expected = sizeof(CrashInfoHeader) + sizeof(CrashInfoDataDynamic);
+
+ iovs[3] = {.iov_base = &thread_info->process_info,
+ .iov_len = sizeof(thread_info->process_info)};
+ } else {
+ // Static executables always use version 1.
+ version = 1;
+ expected = sizeof(CrashInfoHeader) + sizeof(CrashInfoDataStatic);
+
+ iovs[3] = {.iov_base = &thread_info->process_info.abort_msg, .iov_len = sizeof(uintptr_t)};
+ }
errno = 0;
if (fcntl(output_write.get(), F_SETPIPE_SZ, expected) < static_cast<int>(expected)) {
fatal_errno("failed to set pipe buffer size");
}
- struct iovec iovs[] = {
- {.iov_base = &version, .iov_len = sizeof(version)},
- {.iov_base = thread_info->siginfo, .iov_len = sizeof(siginfo_t)},
- {.iov_base = thread_info->ucontext, .iov_len = sizeof(ucontext_t)},
- {.iov_base = &thread_info->abort_msg, .iov_len = sizeof(uintptr_t)},
- {.iov_base = &thread_info->fdsan_table, .iov_len = sizeof(uintptr_t)},
- {.iov_base = &thread_info->gwp_asan_state, .iov_len = sizeof(uintptr_t)},
- {.iov_base = &thread_info->gwp_asan_metadata, .iov_len = sizeof(uintptr_t)},
- };
-
ssize_t rc = TEMP_FAILURE_RETRY(writev(output_write.get(), iovs, arraysize(iovs)));
if (rc == -1) {
fatal_errno("failed to write crash info");
@@ -489,29 +497,19 @@
// check to allow all si_code values in calls coming from inside the house.
}
- void* abort_message = nullptr;
- const gwp_asan::AllocatorState* gwp_asan_state = nullptr;
- const gwp_asan::AllocationMetadata* gwp_asan_metadata = nullptr;
+ debugger_process_info process_info = {};
uintptr_t si_val = reinterpret_cast<uintptr_t>(info->si_ptr);
if (signal_number == BIONIC_SIGNAL_DEBUGGER) {
if (info->si_code == SI_QUEUE && info->si_pid == __getpid()) {
// Allow for the abort message to be explicitly specified via the sigqueue value.
// Keep the bottom bit intact for representing whether we want a backtrace or a tombstone.
if (si_val != kDebuggerdFallbackSivalUintptrRequestDump) {
- abort_message = reinterpret_cast<void*>(si_val & ~1);
+ process_info.abort_msg = reinterpret_cast<void*>(si_val & ~1);
info->si_ptr = reinterpret_cast<void*>(si_val & 1);
}
}
- } else {
- if (g_callbacks.get_abort_message) {
- abort_message = g_callbacks.get_abort_message();
- }
- if (g_callbacks.get_gwp_asan_state) {
- gwp_asan_state = g_callbacks.get_gwp_asan_state();
- }
- if (g_callbacks.get_gwp_asan_metadata) {
- gwp_asan_metadata = g_callbacks.get_gwp_asan_metadata();
- }
+ } else if (g_callbacks.get_process_info) {
+ process_info = g_callbacks.get_process_info();
}
// If sival_int is ~0, it means that the fallback handler has been called
@@ -524,7 +522,7 @@
// This check might be racy if another thread sets NO_NEW_PRIVS, but this should be unlikely,
// you can only set NO_NEW_PRIVS to 1, and the effect should be at worst a single missing
// ANR trace.
- debuggerd_fallback_handler(info, static_cast<ucontext_t*>(context), abort_message);
+ debuggerd_fallback_handler(info, static_cast<ucontext_t*>(context), process_info.abort_msg);
resend_signal(info);
return;
}
@@ -543,10 +541,7 @@
.pseudothread_tid = -1,
.siginfo = info,
.ucontext = context,
- .abort_msg = reinterpret_cast<uintptr_t>(abort_message),
- .fdsan_table = reinterpret_cast<uintptr_t>(android_fdsan_get_fd_table()),
- .gwp_asan_state = reinterpret_cast<uintptr_t>(gwp_asan_state),
- .gwp_asan_metadata = reinterpret_cast<uintptr_t>(gwp_asan_metadata),
+ .process_info = process_info,
};
// Set PR_SET_DUMPABLE to 1, so that crash_dump can ptrace us.
diff --git a/debuggerd/include/debuggerd/handler.h b/debuggerd/include/debuggerd/handler.h
index 665d24a..6650294 100644
--- a/debuggerd/include/debuggerd/handler.h
+++ b/debuggerd/include/debuggerd/handler.h
@@ -33,13 +33,20 @@
struct AllocationMetadata;
}; // namespace gwp_asan
+// When updating this data structure, CrashInfoDataDynamic and the code in
+// ReadCrashInfo() must also be updated.
+struct debugger_process_info {
+ void* abort_msg;
+ void* fdsan_table;
+ const gwp_asan::AllocatorState* gwp_asan_state;
+ const gwp_asan::AllocationMetadata* gwp_asan_metadata;
+};
+
// These callbacks are called in a signal handler, and thus must be async signal safe.
// If null, the callbacks will not be called.
typedef struct {
- struct abort_msg_t* (*get_abort_message)();
+ debugger_process_info (*get_process_info)();
void (*post_dump)();
- const struct gwp_asan::AllocatorState* (*get_gwp_asan_state)();
- const struct gwp_asan::AllocationMetadata* (*get_gwp_asan_metadata)();
} debuggerd_callbacks_t;
void debuggerd_init(debuggerd_callbacks_t* callbacks);
diff --git a/debuggerd/protocol.h b/debuggerd/protocol.h
index bf53864..e85660c 100644
--- a/debuggerd/protocol.h
+++ b/debuggerd/protocol.h
@@ -85,17 +85,14 @@
uint32_t version;
};
-struct __attribute__((__packed__)) CrashInfoDataV1 {
+struct __attribute__((__packed__)) CrashInfoDataStatic {
siginfo_t siginfo;
ucontext_t ucontext;
uintptr_t abort_msg_address;
};
-struct __attribute__((__packed__)) CrashInfoDataV2 : public CrashInfoDataV1 {
+struct __attribute__((__packed__)) CrashInfoDataDynamic : public CrashInfoDataStatic {
uintptr_t fdsan_table_address;
-};
-
-struct __attribute__((__packed__)) CrashInfoDataV3 : public CrashInfoDataV2 {
uintptr_t gwp_asan_state;
uintptr_t gwp_asan_metadata;
};
@@ -103,8 +100,7 @@
struct __attribute__((__packed__)) CrashInfo {
CrashInfoHeader header;
union {
- CrashInfoDataV1 v1;
- CrashInfoDataV2 v2;
- CrashInfoDataV3 v3;
+ CrashInfoDataStatic s;
+ CrashInfoDataDynamic d;
} data;
};