Merge pull request #16 from parca-dev/coredump-fix

Fix coredump compilation
parca-dev · Oct 15, 2024 · 63655fc · 63655fc
2 parents 433e6e3 + e5655f6
commit 63655fc
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diff --git a/support/ebpf/interpreter_dispatcher.ebpf.c b/support/ebpf/interpreter_dispatcher.ebpf.c
@@ -324,6 +324,13 @@ bool get_go_custom_labels(struct pt_regs *ctx, UnwindState *state, void *offsets
                 DEBUG_PRINT("failed to read custom label: value too long");
                 continue;
             }
+
+#ifdef TESTING_COREDUMP
+            if (val_len > CUSTOM_LABEL_MAX_VAL_LEN)
+                res = bpf_probe_read(lbl->val.val_bytes, val_len, map_value->values[i].str);
+            else
+                res = -1;
+#else 
             // The following assembly statement is equivalent to:
             // if (val_len > CUSTOM_LABEL_MAX_VAL_LEN)
             //     res = bpf_probe_read(lbl->val, val_len, map_value->values[i].str);
@@ -353,6 +360,7 @@ bool get_go_custom_labels(struct pt_regs *ctx, UnwindState *state, void *offsets
                   // all r0-r5 are clobbered since we make a function call.
                 : "r0", "r1", "r2", "r3", "r4", "r5", "memory"
             );
+#endif
             // clang-format on
             if (res) {
                 DEBUG_PRINT("failed to read value for custom label: %ld", res);

diff --git a/support/ebpf/opaquify.h b/support/ebpf/opaquify.h
@@ -1,6 +1,7 @@
 #ifndef OPTI_OPAQUIFY_H
 #define OPTI_OPAQUIFY_H
 
+#ifndef TESTING_COREDUMP
 #include "bpfdefs.h"
 // Hack to thwart the verifier's detection of variable bounds.
 //
@@ -54,6 +55,12 @@ u64 opaquify64(u64 val, u64 seed) {
     );
     return val;
 }
+#else
+static inline __attribute__((__always_inline__))
+u64 opaquify64(u64 val, u64 seed) {
+    return val;
+}
+#endif
 
 
 #endif
diff --git a/tools/coredump/ebpfcode.go b/tools/coredump/ebpfcode.go
@@ -22,6 +22,7 @@ package main
 #include <stdarg.h>
 #include <setjmp.h>
 #include "../../support/ebpf/types.h"
+#include "../../support/ebpf/opaquify.h"
 
 struct cgo_ctx {
 	jmp_buf jmpbuf;