From 18d864774916865ec44ccd011a4caf730943f0e9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Andreas=20M=C3=BCller?= <schnitzeltony@gmail.com>
Date: Mon, 20 Apr 2020 23:56:48 +0200
Subject: [PATCH] Fix sandbox 'Aw, snap' for syscalls 403 and 407
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* syscall 403: reported by ArchLinux users [1-2]
* syscall 407: reported by me [3]

Looking at [4-5] it seems that glibc (>=2.31?) introduced extra syscalls for
32Bit systems to handle time64:

* __NR_clock_gettime -> __NR_clock_gettime64
* __NR_clock_nanosleep -> __NR_clock_nanosleep_time64

To fix
| ../../sandbox/linux/seccomp-bpf-helpers/sigsys_handlers.cc:**CRASHING**:seccomp-bpf failure in syscall 0403
| ../../sandbox/linux/seccomp-bpf-helpers/sigsys_handlers.cc:**CRASHING**:seccomp-bpf failure in syscall 0407

we handle new systemcalls in the same way as 64bit systems do and 32bit systems
did before glibc 2.31.

[1] https://bugs.archlinux32.org/index.php?do=details&task_id=105
[2] https://bbs.archlinux32.org/viewtopic.php?id=2897
[3] https://github.com/OSSystems/meta-browser/issues/357
[4] https://sourceware.org/git/?p=glibc.git;a=commit;h=2e44b10b42d68d9887ccab17b76db5d7bbae4fb6
[5] https://github.com/bminor/glibc/blob/019d828669df966dc4ef2684fce0b1c17bef9aae/sysdeps/unix/sysv/linux/clock_gettime.c#L30

Upstream Status: Pending [Have no idea where to send this]

Signed-off-by: Andreas Müller <schnitzeltony@gmail.com>
---
 sandbox/linux/seccomp-bpf-helpers/baseline_policy.cc     | 9 ++++++++-
 .../syscall_parameters_restrictions_unittests.cc         | 6 ++++++
 sandbox/linux/seccomp-bpf-helpers/syscall_sets.cc        | 6 ++++++
 sandbox/linux/system_headers/arm_linux_syscalls.h        | 8 ++++++++
 sandbox/linux/system_headers/mips_linux_syscalls.h       | 8 ++++++++
 5 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/sandbox/linux/seccomp-bpf-helpers/baseline_policy.cc b/sandbox/linux/seccomp-bpf-helpers/baseline_policy.cc
index 768025ce1..87025d917 100644
--- a/sandbox/linux/seccomp-bpf-helpers/baseline_policy.cc
+++ b/sandbox/linux/seccomp-bpf-helpers/baseline_policy.cc
@@ -148,7 +148,14 @@ ResultExpr EvaluateSyscallImpl(int fs_denied_errno,
     return Allow();
 #endif
 
-  if (sysno == __NR_clock_gettime || sysno == __NR_clock_nanosleep) {
+  if (sysno == __NR_clock_gettime || sysno == __NR_clock_nanosleep
+#if defined(__NR_clock_gettime64)
+                                  || sysno == __NR_clock_gettime64
+#endif
+#if defined(__NR_clock_nanosleep_time64)
+                                  || sysno == __NR_clock_nanosleep_time64
+#endif
+  ) {
     return RestrictClockID();
   }
 
diff --git a/sandbox/linux/seccomp-bpf-helpers/syscall_parameters_restrictions_unittests.cc b/sandbox/linux/seccomp-bpf-helpers/syscall_parameters_restrictions_unittests.cc
index b6c8c6377..245bc7131 100644
--- a/sandbox/linux/seccomp-bpf-helpers/syscall_parameters_restrictions_unittests.cc
+++ b/sandbox/linux/seccomp-bpf-helpers/syscall_parameters_restrictions_unittests.cc
@@ -60,6 +60,12 @@ class RestrictClockIdPolicy : public bpf_dsl::Policy {
       case __NR_clock_gettime:
       case __NR_clock_getres:
       case __NR_clock_nanosleep:
+#if defined(__NR_clock_nanosleep_time64)
+      case __NR_clock_nanosleep_time64:
+#endif
+#if defined(__NR_clock_gettime64)
+      case __NR_clock_gettime64:
+#endif
         return RestrictClockID();
       default:
         return Allow();
diff --git a/sandbox/linux/seccomp-bpf-helpers/syscall_sets.cc b/sandbox/linux/seccomp-bpf-helpers/syscall_sets.cc
index d9d18822f..8bc262235 100644
--- a/sandbox/linux/seccomp-bpf-helpers/syscall_sets.cc
+++ b/sandbox/linux/seccomp-bpf-helpers/syscall_sets.cc
@@ -39,6 +39,12 @@ bool SyscallSets::IsAllowedGettime(int sysno) {
                                 // filtered by RestrictClokID().
     case __NR_clock_gettime:    // Parameters filtered by RestrictClockID().
     case __NR_clock_nanosleep:  // Parameters filtered by RestrictClockID().
+#if defined(__NR_clock_gettime64)
+    case __NR_clock_gettime64:  // Parameters filtered by RestrictClockID().
+#endif
+#if defined(__NR_clock_nanosleep_time64)
+    case __NR_clock_nanosleep_time64:  // Parameters filtered by RestrictClockID().
+#endif
     case __NR_clock_settime:    // Privileged.
 #if defined(__i386__) || \
     (defined(ARCH_CPU_MIPS_FAMILY) && defined(ARCH_CPU_32_BITS))
diff --git a/sandbox/linux/system_headers/arm_linux_syscalls.h b/sandbox/linux/system_headers/arm_linux_syscalls.h
index 1addd5384..5de2162f9 100644
--- a/sandbox/linux/system_headers/arm_linux_syscalls.h
+++ b/sandbox/linux/system_headers/arm_linux_syscalls.h
@@ -1441,6 +1441,14 @@
 #define __NR_io_pgetevents (__NR_SYSCALL_BASE+399)
 #endif
 
+#if !defined(__NR_clock_gettime64)
+#define __NR_clock_gettime64 (__NR_SYSCALL_BASE+403)
+#endif
+
+#if !defined(__NR_clock_nanosleep_time64)
+#define __NR_clock_nanosleep_time64 (__NR_SYSCALL_BASE+407)
+#endif
+
 // ARM private syscalls.
 #if !defined(__ARM_NR_BASE)
 #define __ARM_NR_BASE (__NR_SYSCALL_BASE + 0xF0000)
diff --git a/sandbox/linux/system_headers/mips_linux_syscalls.h b/sandbox/linux/system_headers/mips_linux_syscalls.h
index ddbf97f3d..fa01b3bbc 100644
--- a/sandbox/linux/system_headers/mips_linux_syscalls.h
+++ b/sandbox/linux/system_headers/mips_linux_syscalls.h
@@ -1433,4 +1433,12 @@
 #define __NR_memfd_create (__NR_Linux + 354)
 #endif
 
+#if !defined(__NR_clock_gettime64)
+#define __NR_clock_gettime64 (__NR_Linux + 403)
+#endif
+
+#if !defined(__NR_clock_nanosleep_time64)
+#define __NR_clock_nanosleep_time64 (__NR_Linux + 407)
+#endif
+
 #endif  // SANDBOX_LINUX_SYSTEM_HEADERS_MIPS_LINUX_SYSCALLS_H_
-- 
2.21.1