From 83a9ccb1265dcdeeb8bf17205e00b751f86641d3 Mon Sep 17 00:00:00 2001
From: Ho Cheung <hocheung@chromium.org>
Date: Tue, 21 Apr 2026 08:19:53 -0700
Subject: [PATCH] [sandbox] Fix SYS_SECCOMP conflict with newer glibc

glibc now exposes SYS_SECCOMP in signal headers, which conflicts with
Chromium's fallback macro in linux_seccomp.h.

Stop defining SYS_SECCOMP in the public compat header and use a local
fallback in trap.cc instead.

Test: Tested on an Ubuntu 26.04 container using use_sysroot = false.
Bug: 456218403
Change-Id: I73ddfa85453dd9d524b64b4c1bca4f95b82c9f2b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7781604
Reviewed-by: Elly <ellyjones@chromium.org>
Commit-Queue: Aaron Teo <hocheung@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1618207}
---

diff --git a/sandbox/linux/seccomp-bpf/trap.cc b/sandbox/linux/seccomp-bpf/trap.cc
index 1316786d..212e80e 100644
--- a/src/3rdparty/chromium/sandbox/linux/seccomp-bpf/trap.cc
+++ b/src/3rdparty/chromium/sandbox/linux/seccomp-bpf/trap.cc
@@ -29,6 +29,12 @@
 
 namespace {
 
+#if defined(SYS_SECCOMP)
+constexpr int kSigsysSeccompCode = SYS_SECCOMP;
+#else
+constexpr int kSigsysSeccompCode = 1;
+#endif
+
 struct arch_sigsys {
   // RAW_PTR_EXCLUSION: Points to a code address given to us by the kernel.
   RAW_PTR_EXCLUSION void* ip;
@@ -151,7 +157,7 @@
   // Various sanity checks to make sure we actually received a signal
   // triggered by a BPF filter. If something else triggered SIGSYS
   // (e.g. kill()), there is really nothing we can do with this signal.
-  if (nr != LINUX_SIGSYS || info->si_code != SYS_SECCOMP || !ctx ||
+  if (nr != LINUX_SIGSYS || info->si_code != kSigsysSeccompCode || !ctx ||
       info->si_errno <= 0 ||
       static_cast<size_t>(info->si_errno) > trap_array_size_) {
     // ATI drivers seem to send SIGSYS, so this cannot be FATAL.
@@ -162,7 +168,6 @@
     return;
   }
 
-
   // Obtain the siginfo information that is specific to SIGSYS.
   struct arch_sigsys sigsys;
 #if defined(si_call_addr)
diff --git a/sandbox/linux/system_headers/linux_seccomp.h b/sandbox/linux/system_headers/linux_seccomp.h
index 8690a96..8ebf4045 100644
--- a/src/3rdparty/chromium/sandbox/linux/system_headers/linux_seccomp.h
+++ b/src/3rdparty/chromium/sandbox/linux/system_headers/linux_seccomp.h
@@ -214,8 +214,4 @@
 #define SECCOMP_RET_INVALID 0x00010000U  // Illegal return value
 #endif
 
-#ifndef SYS_SECCOMP
-#define SYS_SECCOMP                   1
-#endif
-
 #endif  // SANDBOX_LINUX_SYSTEM_HEADERS_LINUX_SECCOMP_H_