Update debuggerd for stack MTE.
Two things need changing for debuggerd_test to pass.
1. The seccomp policy needs to allow for PROT_MTE (0x20) in both
mprotect() and mmap(). Stack MTE processes do a mprotect()/mmap() of
the stack when launching a process.
2. The fault address and stack pointer need to be untagged when trying
to figure out the stack overflow cause.
Bug: 320448268
Bug: 292478827
Test: atest debuggerd_test --iterations=10
Change-Id: I56471c32ca40edffbb61b7547bdf2b85a6eb1ff7
diff --git a/debuggerd/libdebuggerd/tombstone_proto.cpp b/debuggerd/libdebuggerd/tombstone_proto.cpp
index 744bfab..ca25510 100644
--- a/debuggerd/libdebuggerd/tombstone_proto.cpp
+++ b/debuggerd/libdebuggerd/tombstone_proto.cpp
@@ -94,6 +94,11 @@
static std::optional<std::string> get_stack_overflow_cause(uint64_t fault_addr, uint64_t sp,
unwindstack::Maps* maps) {
+ // Under stack MTE the stack pointer and/or the fault address can be tagged.
+ // In order to calculate deltas between them, strip off the tags off both
+ // addresses.
+ fault_addr = untag_address(fault_addr);
+ sp = untag_address(sp);
static constexpr uint64_t kMaxDifferenceBytes = 256;
uint64_t difference;
if (sp >= fault_addr) {
diff --git a/debuggerd/seccomp_policy/crash_dump.arm64.policy b/debuggerd/seccomp_policy/crash_dump.arm64.policy
index adf8738..c5d10d6 100644
--- a/debuggerd/seccomp_policy/crash_dump.arm64.policy
+++ b/debuggerd/seccomp_policy/crash_dump.arm64.policy
@@ -28,11 +28,11 @@
rt_tgsigqueueinfo: 1
prctl: arg0 == PR_GET_NO_NEW_PRIVS || arg0 == 0x53564d41 || arg0 == PR_PAC_RESET_KEYS || arg0 == 56 || arg0 == 61
madvise: 1
-mprotect: arg2 in 0x1|0x2
+mprotect: arg2 in 0x1|0x2|0x20
munmap: 1
getuid: 1
fstat: 1
-mmap: arg2 in 0x1|0x2
+mmap: arg2 in 0x1|0x2|0x20
geteuid: 1
getgid: 1
getegid: 1