Remove obsolete seccomp_unwinder for legacy (pre-BPF) sandbox

The PopSeccompStackFrame was introduced to deal with stack frames
originated in the legacy seccomp sandbox. The only user of that
sandbox was Google Chrome, but the legacy sandbox has been
deprecated in 2013 (crrev.com/1290643003) in favor of the new
bpf sandbox.
Removing this dead code as it has some small bound checking bug
which causes occasional crashes in WebView (which are totally
unrelated to the sandbox).

Note: this will require a corresponding change in the chromium
GYP/GN build files to roll.

BUG=665,chromium:477444
R=jln@chromium.org, mark@chromium.org, torne@chromium.org

Review URL: https://codereview.chromium.org/1299593003 .

git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1492 4c0a9323-5329-0410-9bdc-e9ce6186880e

2 files changed, 0 insertions, 204 deletions

diff --git a/src/client/linux/dump_writer_common/seccomp_unwinder.cc b/src/client/linux/dump_writer_common/seccomp_unwinder.cc
deleted file mode 100644
index e9d1ec78..00000000
--- a/src/client/linux/dump_writer_common/seccomp_unwinder.cc
+++ /dev/null
@@ -1,154 +0,0 @@
-// Copyright (c) 2014, Google Inc.
-// All rights reserved.
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-#include "client/linux/dump_writer_common/seccomp_unwinder.h"
-
-#include <string.h>
-
-#include "google_breakpad/common/minidump_format.h"
-#include "common/linux/linux_libc_support.h"
-
-namespace google_breakpad {
-
-void SeccompUnwinder::PopSeccompStackFrame(RawContextCPU* cpu,
-                                           const MDRawThread& thread,
-                                           uint8_t* stack_copy) {
-#if defined(__x86_64)
-  uint64_t bp = cpu->rbp;
-  uint64_t top = thread.stack.start_of_memory_range;
-  for (int i = 4; i--; ) {
-    if (bp < top ||
-        bp > thread.stack.start_of_memory_range +
-        thread.stack.memory.data_size - sizeof(bp) ||
-        bp & 1) {
-      break;
-    }
-    uint64_t old_top = top;
-    top = bp;
-    uint8_t* bp_addr = stack_copy + bp - thread.stack.start_of_memory_range;
-    my_memcpy(&bp, bp_addr, sizeof(bp));
-    if (bp == 0xDEADBEEFDEADBEEFull) {
-      struct {
-        uint64_t r15;
-        uint64_t r14;
-        uint64_t r13;
-        uint64_t r12;
-        uint64_t r11;
-        uint64_t r10;
-        uint64_t r9;
-        uint64_t r8;
-        uint64_t rdi;
-        uint64_t rsi;
-        uint64_t rdx;
-        uint64_t rcx;
-        uint64_t rbx;
-        uint64_t deadbeef;
-        uint64_t rbp;
-        uint64_t fakeret;
-        uint64_t ret;
-        /* char redzone[128]; */
-      } seccomp_stackframe;
-      if (top - offsetof(__typeof__(seccomp_stackframe), deadbeef) < old_top ||
-          top - offsetof(__typeof__(seccomp_stackframe), deadbeef) +
-          sizeof(seccomp_stackframe) >
-          thread.stack.start_of_memory_range+thread.stack.memory.data_size) {
-        break;
-      }
-      my_memcpy(&seccomp_stackframe,
-                bp_addr - offsetof(__typeof__(seccomp_stackframe), deadbeef),
-                sizeof(seccomp_stackframe));
-      cpu->rbx = seccomp_stackframe.rbx;
-      cpu->rcx = seccomp_stackframe.rcx;
-      cpu->rdx = seccomp_stackframe.rdx;
-      cpu->rsi = seccomp_stackframe.rsi;
-      cpu->rdi = seccomp_stackframe.rdi;
-      cpu->rbp = seccomp_stackframe.rbp;
-      cpu->rsp = top + 4*sizeof(uint64_t) + 128;
-      cpu->r8  = seccomp_stackframe.r8;
-      cpu->r9  = seccomp_stackframe.r9;
-      cpu->r10 = seccomp_stackframe.r10;
-      cpu->r11 = seccomp_stackframe.r11;
-      cpu->r12 = seccomp_stackframe.r12;
-      cpu->r13 = seccomp_stackframe.r13;
-      cpu->r14 = seccomp_stackframe.r14;
-      cpu->r15 = seccomp_stackframe.r15;
-      cpu->rip = seccomp_stackframe.fakeret;
-      return;
-    }
-  }
-#elif defined(__i386__)
-  uint32_t bp = cpu->ebp;
-  uint32_t top = thread.stack.start_of_memory_range;
-  for (int i = 4; i--; ) {
-    if (bp < top ||
-        bp > thread.stack.start_of_memory_range +
-        thread.stack.memory.data_size - sizeof(bp) ||
-        bp & 1) {
-      break;
-    }
-    uint32_t old_top = top;
-    top = bp;
-    uint8_t* bp_addr = stack_copy + bp - thread.stack.start_of_memory_range;
-    my_memcpy(&bp, bp_addr, sizeof(bp));
-    if (bp == 0xDEADBEEFu) {
-      struct {
-        uint32_t edi;
-        uint32_t esi;
-        uint32_t edx;
-        uint32_t ecx;
-        uint32_t ebx;
-        uint32_t deadbeef;
-        uint32_t ebp;
-        uint32_t fakeret;
-        uint32_t ret;
-      } seccomp_stackframe;
-      if (top - offsetof(__typeof__(seccomp_stackframe), deadbeef) < old_top ||
-          top - offsetof(__typeof__(seccomp_stackframe), deadbeef) +
-          sizeof(seccomp_stackframe) >
-          thread.stack.start_of_memory_range+thread.stack.memory.data_size) {
-        break;
-      }
-      my_memcpy(&seccomp_stackframe,
-                bp_addr - offsetof(__typeof__(seccomp_stackframe), deadbeef),
-                sizeof(seccomp_stackframe));
-      cpu->ebx = seccomp_stackframe.ebx;
-      cpu->ecx = seccomp_stackframe.ecx;
-      cpu->edx = seccomp_stackframe.edx;
-      cpu->esi = seccomp_stackframe.esi;
-      cpu->edi = seccomp_stackframe.edi;
-      cpu->ebp = seccomp_stackframe.ebp;
-      cpu->esp = top + 4*sizeof(void*);
-      cpu->eip = seccomp_stackframe.fakeret;
-      return;
-    }
-  }
-#endif
-}
-
-}  // namespace google_breakpad
diff --git a/src/client/linux/dump_writer_common/seccomp_unwinder.h b/src/client/linux/dump_writer_common/seccomp_unwinder.h
deleted file mode 100644
index 0f5637b6..00000000
--- a/src/client/linux/dump_writer_common/seccomp_unwinder.h
+++ /dev/null
@@ -1,50 +0,0 @@
-// Copyright (c) 2014, Google Inc.
-// All rights reserved.
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-#ifndef CLIENT_LINUX_DUMP_WRITER_COMMON_SECCOMP_UNWINDER_H
-#define CLIENT_LINUX_DUMP_WRITER_COMMON_SECCOMP_UNWINDER_H
-
-#include "client/linux/dump_writer_common/raw_context_cpu.h"
-#include "google_breakpad/common/minidump_format.h"
-
-namespace google_breakpad {
-
-struct SeccompUnwinder {
-
-  // Check if the top of the stack is part of a system call that has been
-  // redirected by the seccomp sandbox. If so, try to pop the stack frames
-  // all the way back to the point where the interception happened.
-  static void PopSeccompStackFrame(RawContextCPU* cpu,
-                                   const MDRawThread& thread,
-                                   uint8_t* stack_copy);
-};
-
-}  // namespace google_breakpad
-
-#endif  // CLIENT_LINUX_DUMP_WRITER_COMMON_SECCOMP_UNWINDER_H