commit 4a6ebc19a7e2d013a0e2ca79452ea733b1d5b686
author Richard Henderson <richard.henderson@linaro.org> Tue Aug 22 22:07:41 2023 -0700
committer Richard Henderson <richard.henderson@linaro.org> Wed Oct 18 15:34:34 2023 -0700
tree 82f422e651e38ed3343ae8043956c5aa211aebd9
parent f4e1168198a6306c3e337f2b91b1213f5bef52af

linux-user: Detect and report host SIGILL, SIGFPE, SIGTRAP

These signals, when not spoofed via kill(), are always bugs.
Use die_from_signal to report this sensibly.

Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

linux-user/signal.c

diff --git a/linux-user/signal.c b/linux-user/signal.c
index 706b8ac..b67077f 100644
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -796,6 +796,43 @@
             break;
         }
         break;
+    case SIGILL:
+        sig = "ILL";
+        switch (info->si_code) {
+        case ILL_ILLOPC:
+            code = "ILLOPC";
+            break;
+        case ILL_ILLOPN:
+            code = "ILLOPN";
+            break;
+        case ILL_ILLADR:
+            code = "ILLADR";
+            break;
+        case ILL_PRVOPC:
+            code = "PRVOPC";
+            break;
+        case ILL_PRVREG:
+            code = "PRVREG";
+            break;
+        case ILL_COPROC:
+            code = "COPROC";
+            break;
+        }
+        break;
+    case SIGFPE:
+        sig = "FPE";
+        switch (info->si_code) {
+        case FPE_INTDIV:
+            code = "INTDIV";
+            break;
+        case FPE_INTOVF:
+            code = "INTOVF";
+            break;
+        }
+        break;
+    case SIGTRAP:
+        sig = "TRAP";
+        break;
     default:
         snprintf(sigbuf, sizeof(sigbuf), "%d", info->si_signo);
         sig = sigbuf;
@@ -900,7 +937,8 @@
 
     /*
      * Non-spoofed SIGSEGV and SIGBUS are synchronous, and need special
-     * handling wrt signal blocking and unwinding.
+     * handling wrt signal blocking and unwinding.  Non-spoofed SIGILL,
+     * SIGFPE, SIGTRAP are always host bugs.
      */
     if (info->si_code > 0) {
         switch (host_sig) {
@@ -912,6 +950,10 @@
             host_sigbus_handler(cpu, info, uc);
             sync_sig = true;
             break;
+        case SIGILL:
+        case SIGFPE:
+        case SIGTRAP:
+            die_from_signal(info);
         }
     }