From 4adb7eca6ab2148026a9d2e00379cedfc2038a0d Mon Sep 17 00:00:00 2001
From: Jacob Young <jacobly0@users.noreply.github.com>
Date: Mon, 12 May 2025 19:03:04 -0400
Subject: [PATCH] debug: correctly detect missing entries in `.eh_frame_hdr`

---
 lib/std/debug/Dwarf.zig    | 4 +++-
 lib/std/debug/SelfInfo.zig | 2 +-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/std/debug/Dwarf.zig b/lib/std/debug/Dwarf.zig
index e5d47ba491..06b6c81075 100644
--- a/lib/std/debug/Dwarf.zig
+++ b/lib/std/debug/Dwarf.zig
@@ -402,7 +402,7 @@ pub const ExceptionFrameHeader = struct {
             }
         }
 
-        if (len == 0) return bad();
+        if (len == 0) return missing();
         fbr.pos = left * entry_size;
 
         // Read past the pc_begin field of the entry
@@ -460,6 +460,8 @@ pub const ExceptionFrameHeader = struct {
             @sizeOf(usize),
             native_endian,
         );
+
+        if (pc < fde.pc_begin or pc >= fde.pc_begin + fde.pc_range) return missing();
     }
 };
 
diff --git a/lib/std/debug/SelfInfo.zig b/lib/std/debug/SelfInfo.zig
index ea7ecac4ed..70f3075de7 100644
--- a/lib/std/debug/SelfInfo.zig
+++ b/lib/std/debug/SelfInfo.zig
@@ -1633,7 +1633,7 @@ pub fn unwindFrameDwarf(
                 &cie,
                 &fde,
             ) catch |err| switch (err) {
-                error.InvalidDebugInfo => {
+                error.MissingDebugInfo => {
                     // `.eh_frame_hdr` appears to be incomplete, so go ahead and populate `cie_map`
                     // and `fde_list`, and fall back to the binary search logic below.
                     try di.scanCieFdeInfo(allocator, base_address);