)]}' { "commit": "fdf0ed6f7420cefec0131eab86ba54755245fee2", "tree": "ade34da338c958f75b10e955fb23e78e686d65cd", "parents": [ "60d51dfed16480aef9c21690a1e1767c19dd9393" ], "author": { "name": "Nicolas Hillegeer", "email": "aktau@google.com", "time": "Wed Oct 09 07:44:18 2024 -0700" }, "committer": { "name": "Gopher Robot", "email": "gobot@golang.org", "time": "Wed Oct 09 16:02:30 2024 +0000" }, "message": "internal/gocore: support PIE ELF binaries\n\nGo binaries built with `-buildmode\u003dpie` are loaded at random addresses\n(ASLR) in memory by Linux.\n\nBefore this change, the mappings read from the `NT_NOTE` section of the\nELF binary matches the exe mappings:\n\n # From NT_NOTE:\n 0x400000-0x491000 ---- 593920 /tmp/TestVersionsgoroot#003207751013/001/test.exe+0x0\n 0x491000-0x54b000 ---- 761856 /tmp/TestVersionsgoroot#003207751013/001/test.exe+0x91000\n 0x54b000-0x556000 ---- 45056 /tmp/TestVersionsgoroot#003207751013/001/test.exe+0x14b000\n\n # From executable:\n 0x400000-0x491000 r-xp 593920 /tmp/TestVersionsgoroot#003207751013/001/test.exe+0x0\n 0x491000-0x54b000 r--p 761856 /tmp/TestVersionsgoroot#003207751013/001/test.exe+0x91000\n 0x54b000-0x555000 rw-p 40960 /tmp/TestVersionsgoroot#003207751013/001/test.exe+0x14b000\n 0x555000-0x579000 rw-p 147456 anon+0x-440\n\n # From core\n 0xc000000000-0xc000400000 rw-p 4194304 /tmp/TestVersionsgoroot#003207751013/001/core+0x32000\n 0x7f8b17c00000-0x7f8b19c00000 rw-p 33554432 /tmp/TestVersionsgoroot#003207751013/001/core+0x432000\n 0x7f8b29d80000-0x7f8b29d81000 rw-p 4096 /tmp/TestVersionsgoroot#003207751013/001/core+0x2432000\n 0x7f8b49d80000-0x7f8b49d81000 rw-p 4096 /tmp/TestVersionsgoroot#003207751013/001/core+0x2433000\n 0x7f8b5bc30000-0x7f8b5bc31000 rw-p 4096 /tmp/TestVersionsgoroot#003207751013/001/core+0x2434000\n 0x7f8b5e006000-0x7f8b5e007000 rw-p 4096 /tmp/TestVersionsgoroot#003207751013/001/core+0x2435000\n 0x7f8b5e466000-0x7f8b5e4c6000 rw-p 393216 /tmp/TestVersionsgoroot#003207751013/001/core+0x2436000\n 0x7f8b5e4c6000-0x7f8b5e5c6000 rw-p 1048576 /tmp/TestVersionsgoroot#003207751013/001/core+0x2496000\n 0x7f8b5e5c6000-0x7f8b5e5d7000 rw-p 69632 /tmp/TestVersionsgoroot#003207751013/001/core+0x2596000\n 0x7f8b5e657000-0x7f8b5e658000 rw-p 4096 /tmp/TestVersionsgoroot#003207751013/001/core+0x25a7000\n 0x7f8b5e6d7000-0x7f8b5e737000 rw-p 393216 /tmp/TestVersionsgoroot#003207751013/001/core+0x25a8000\n 0x7f8b5e737000-0x7f8b5e73b000 r--p 16384 /tmp/TestVersionsgoroot#003207751013/001/core+0x2608000\n 0x7f8b5e73b000-0x7f8b5e73d000 r-xp 8192 /tmp/TestVersionsgoroot#003207751013/001/core+0x260c000\n 0x7ffd88d3c000-0x7ffd88d5e000 rw-p 139264 /tmp/TestVersionsgoroot#003207751013/001/core+0x260e000\n\nAnd things worked fine. But, with PIE binaries, we see the following raw\naddresses when loading (e.g.):\n\n # From NT_NOTE:\n 0x563f53d35000-0x563f53dc7000 ---- 598016 /tmp/TestVersionsgoroot-buildmode\u003dpie3327190927/001/test.exe+0x0\n 0x563f53dc7000-0x563f53e10000 ---- 299008 /tmp/TestVersionsgoroot-buildmode\u003dpie3327190927/001/test.exe+0x92000\n 0x563f53e10000-0x563f53ea3000 ---- 602112 /tmp/TestVersionsgoroot-buildmode\u003dpie3327190927/001/test.exe+0xdb000\n 0x563f53ea3000-0x563f53eaf000 ---- 49152 /tmp/TestVersionsgoroot-buildmode\u003dpie3327190927/001/test.exe+0x16e000\n 0x7ff5d0deb000-0x7ff5d0dec000 ---- 4096 /usr/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2+0x0\n 0x7ff5d0dec000-0x7ff5d0e11000 ---- 151552 /usr/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2+0x1000\n 0x7ff5d0e11000-0x7ff5d0e1b000 ---- 40960 /usr/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2+0x26000\n 0x7ff5d0e1b000-0x7ff5d0e1f000 ---- 16384 /usr/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2+0x30000\n\n # From executable:\n 0x400000-0x492000 r-xp 598016 /tmp/TestVersionsgoroot-buildmode\u003dpie3327190927/001/test.exe+0x0\n 0x492000-0x4db000 r--p 299008 /tmp/TestVersionsgoroot-buildmode\u003dpie3327190927/001/test.exe+0x92000\n 0x4db000-0x56f000 rw-p 606208 /tmp/TestVersionsgoroot-buildmode\u003dpie3327190927/001/test.exe+0xdb000\n 0x56f000-0x579000 rw-p 40960 /tmp/TestVersionsgoroot-buildmode\u003dpie3327190927/001/test.exe+0x16f000\n 0x579000-0x59d000 rw-p 147456 anon+0x-460\n\n # From core\n 0xc000000000-0xc000400000 rw-p 4194304 /tmp/TestVersionsgoroot-buildmode\u003dpie3327190927/001/core+0x3000\n 0x563f53d35000-0x563f53d36000 r-xp 4096 /tmp/TestVersionsgoroot-buildmode\u003dpie3327190927/001/core+0x403000\n 0x563f53d36000-0x563f53dc7000 r-xp 593920 anon+0x0\n 0x563f53dc7000-0x563f53e10000 r--p 299008 anon+0x0\n 0x563f53e10000-0x563f53ea3000 r--p 602112 /tmp/TestVersionsgoroot-buildmode\u003dpie3327190927/001/core+0x404000\n 0x563f53ea3000-0x563f53eaf000 rw-p 49152 /tmp/TestVersionsgoroot-buildmode\u003dpie3327190927/001/core+0x497000\n 0x563f53eaf000-0x563f53ed2000 rw-p 143360 /tmp/TestVersionsgoroot-buildmode\u003dpie3327190927/001/core+0x4a3000\n ...\n 0x7ff5d0deb000-0x7ff5d0dec000 r--p 4096 /tmp/TestVersionsgoroot-buildmode\u003dpie3327190927/001/core+0x26a4000\n 0x7ff5d0dec000-0x7ff5d0e11000 r-xp 151552 anon+0x0\n 0x7ff5d0e11000-0x7ff5d0e1b000 r--p 40960 anon+0x0\n 0x7ff5d0e1b000-0x7ff5d0e1f000 rw-p 16384 /tmp/TestVersionsgoroot-buildmode\u003dpie3327190927/001/core+0x26a5000\n 0x7fff34a26000-0x7fff34a48000 rw-p 139264 /tmp/TestVersionsgoroot-buildmode\u003dpie3327190927/001/core+0x26a9000\n\nThis caused two issues:\n\n 1. The mappings from the executable and the core were not unified\n properly done in `addProgMappings -\u003e splicedMemory.Add` due to the\n address ranges being different. Both existeded in the\n `splicedMemory` set. Normally, the core mappings would override the\n executable mappings when they overlap. To correct for this, add the\n load offset (`staticBase`) to the executable addresses.\n 2. DWARF data (contained in the executable) references the base\n addresses (for example, `allgs` is at 0x4003c4). Due to #1, a lookup\n *would not crash*, but it would read the location from the\n executable. In a PIE binary, such a lookup into the `.data` section\n would be a relocation, and be present in the binary as all zeroes\n (0x0). If #1 were fixed to offset by `staticBase` without fixing #2\n would result in a read from unmapped memory.\n\nInspiration was taken from the Delve commit that added PIE support for\nmultiple platforms/architectures in\nhttps://github.com/go-delve/delve/commit/025d47c6e96e8ab5a2d2c142ae554e760cddabf8.\n\nAlso add tests that this works. I verified that if the changes from\nnon-test files are omitted, the test fails.\n\nChange-Id: Ifa08f71e7ed22320b78bc6015554e997b8ae521d\nReviewed-on: https://go-review.googlesource.com/c/debug/+/618977\nLUCI-TryBot-Result: Go LUCI \u003cgolang-scoped@luci-project-accounts.iam.gserviceaccount.com\u003e\nAuto-Submit: Nicolas Hillegeer \u003caktau@google.com\u003e\nReviewed-by: Michael Knyszek \u003cmknyszek@google.com\u003e\n", "tree_diff": [ { "type": "modify", "old_id": "7890be5ceef8eccf683868d6e5ad6549ca23ace3", "old_mode": 33188, "old_path": "internal/core/process.go", "new_id": "74400e449e29c2453b2752356eeda380d6d458ac", "new_mode": 33188, "new_path": "internal/core/process.go" }, { "type": "modify", "old_id": "967531a7a3036ce2500c3025d431280d91b960c2", "old_mode": 33188, "old_path": "internal/gocore/dwarf.go", "new_id": "e8f9497d492ab2c4c5941e4d48e60d30e8e40513", "new_mode": 33188, "new_path": "internal/gocore/dwarf.go" }, { "type": "modify", "old_id": "91f69c1287a691360a7a68fff5167e012577a8f1", "old_mode": 33188, "old_path": "internal/gocore/gocore_test.go", "new_id": "8c8c58eb45f16f5e4f826afb79bbb70f40f51813", "new_mode": 33188, "new_path": "internal/gocore/gocore_test.go" } ] }