)]}'
{
  "commit": "3fde3398341ba900ed2e1eaecf00799fda66686a",
  "tree": "f2c2a4e1d8883e4fa7ba236e9c3111017425d399",
  "parents": [
    "f1ee6f0fe443129448fc90c42aaafc869a9f636f"
  ],
  "author": {
    "name": "H.J. Lu",
    "email": "hjl.tools@gmail.com",
    "time": "Mon Feb 10 07:58:45 2020 -0800"
  },
  "committer": {
    "name": "H.J. Lu",
    "email": "hjl.tools@gmail.com",
    "time": "Mon Feb 10 08:10:49 2020 -0800"
  },
  "message": "i386: Properly pop restore token in signal frame\n\nLinux CET kernel places a restore token on shadow stack for signal\nhandler to enhance security.  The restore token is 8 byte and aligned\nto 8 bytes.  It is usually transparent to user programs since kernel\nwill pop the restore token when signal handler returns.  But when an\nexception is thrown from a signal handler, now we need to pop the\nrestore token from shadow stack.  For x86-64, we just need to treat\nthe signal frame as normal frame.  For i386, we need to search for\nthe restore token to check if the original shadow stack is 8 byte\naligned.  If the original shadow stack is 8 byte aligned, we just\nneed to pop 2 slots, one restore token, from shadow stack.  Otherwise,\nwe need to pop 3 slots, one restore token + 4 byte padding, from\nshadow stack.\n\nThis patch also includes 2 tests, one has a restore token with 4 byte\npadding and one without.\n\nTested on Linux/x86-64 CET machine with and without -m32.\n\nlibgcc/\n\n\tBackport from mainline\n\tPR libgcc/85334\n\t* config/i386/shadow-stack-unwind.h (_Unwind_Frames_Increment):\n\tNew.\n\ngcc/testsuite/\n\n\tBackport from mainline\n\tPR libgcc/85334\n\t* g++.target/i386/pr85334-1.C: New test.\n\t* g++.target/i386/pr85334-2.C: Likewise.\n\n(cherry picked from commit bf6465d0461234ccd45ae34d5e2375a0bee0081d)\n",
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