{ "number": 36677, "repo": "bitcoin/bitcoin", "url": "https://github.com/bitcoin/bitcoin/pull/36677", "title": "util: Make files opened with fdbridge::fopen noninheritable", "author": "SirECMG", "author_association": "FIRST_TIME_CONTRIBUTOR", "created_at": "2026-10-27T18:51:28Z", "updated_at": "2026-10-30T15:15:05Z", "description_hash": "ba1520dbb95c1862", "age_days": 5, "draft": false, "labels": [ "Utils/log/libs" ], "milestone": null, "base": "master", "head_sha": "17ea8dd8185cc4ebcdb0b1fae2a0d892459e04c4", "head_ref": "u/sirecmg/36668-fopen-inheritable-fix", "head_repo": "SirECMG/bitcoin", "head_history": [ { "t": "2026-10-27T21:06:05Z", "sha": "c354037d4455e41ccf56705fa46187c4a3a09114" }, { "t": "2026-10-28T18:35:43Z", "sha": "9ebc30b17d67d12669babb06ad3549d68664cb97" }, { "t": "2026-10-28T18:40:00Z", "sha": "f2eac03b2eed5789c8ee5a4657588f535a5c3b04" }, { "t": "2026-10-28T18:42:04Z", "sha": "30c974f601a9d4b1d987e0e8d0850faa839d38bb" }, { "t": "2026-10-28T18:59:17Z", "sha": "f2875ebd401a6c8d0f03aaa39e46cf040a2953bf" }, { "t": "2026-10-28T19:03:12Z", "sha": "e423eb6810bbffc72ecd3739b88ef5af86b012c3" }, { "t": "2026-10-28T19:05:05Z", "sha": "55f35a25d390dad5c6182653df87edc1fc963f5b" }, { "t": "2026-10-28T21:25:49Z", "sha": "6a1ff77cfd71ceb9797b31d4545310163b7f4afa" }, { "t": "2026-10-29T17:42:48Z", "sha": "17ea8dd8185cc4ebcdb0b1fae2a0d892459e04c4" } ], "additions": 88, "deletions": 4, "changed_files": 2, "commit_count": 2, "size_bucket": "S", "mergeable_state": "clean", "bot": { "drahtbot": { "present": true, "reviews": {}, "conflicts": [] } }, "acks_parsed": {}, "acks_tally": { "ack": 0, "stale_ack": 0, "concept_ack": 0, "approach_ack": 0, "nack": 0, "concept_nack": 0, "approach_nack": 0 }, "reviews": { "approved": 0, "changes_requested": 0, "distinct_reviewers": [ "ValeraFinebits", "hebasto", "winterrdog" ] }, "signals": { "needs_rebase": false, "ci_failed": false, "mergeable_state": "clean", "last_author_activity": "2026-10-29T17:42:48Z", "last_reviewer_activity": "2026-10-30T11:59:39Z", "last_reviewer": "winterrdog", "author_silent_days": 3, "waiting_on_author_days": 2, "days_since_update": 2 }, "refs": { "mentioned": [ 36668 ], "depends_on": [], "fixes": [ 36668 ], "linked_issues": [ { "number": 36668, "type": "issue", "state": "open", "merged": false, "merged_at": null, "title": "util: Make files opened via `fsbridge::fopen()` not inheritable by child processes" } ], "references": [ { "number": 36668, "type": "issue", "state": "open", "merged": false, "merged_at": null, "title": "util: Make files opened via `fsbridge::fopen()` not inheritable by child processes" } ], "conflicts": [] }, "stack": { "shares_commits_with": [], "based_on": [], "base_for": [] }, "review_paths": [ "src/util/fs.cpp" ], "body": "Fixes #36668\n\nUse the 'e' mode on POSIX to set close-on-exec and the 'N' mode on windows to prevent file handle inheritance by child processes.\n\nThis PR is still in WIP... until I add some test cases and verify that it works on Windows and Mac. I've only tested it on Linux (OpenSUSE Tumbleweed)", "commits": [ { "sha": "082b38544571db6809541091820d21d8ca9b1f1b", "date": "2026-10-29T17:42:25Z", "message": "util: Make fsbridge::fopen files non-inheritable" }, { "sha": "17ea8dd8185cc4ebcdb0b1fae2a0d892459e04c4", "date": "2026-10-29T17:42:33Z", "message": "test: Verify fsbridge::fopen opens non-inheritable files" } ], "timeline": [ { "t": "2026-10-27T21:06:05Z", "kind": "force_push", "who": "SirECMG", "commit": "c354037d4455e41ccf56705fa46187c4a3a09114", "id": "push:c354037d4455e41ccf56705fa46187c4a3a09114" }, { "t": "2026-10-27T21:20:09Z", "kind": "review_comment", "who": "hebasto", "assoc": "MEMBER", "path": "src/util/fs.cpp", "commit": "c354037d4455e41ccf56705fa46187c4a3a09114", "in_reply_to": null, "text": "Is \"e\" available on all non-Windows systems?", "id": "rc:4394300695", "url": "https://github.com/bitcoin/bitcoin/pull/36677#discussion_r4394300695", "hash": "d2317e1c5c7342e6", "edited": "2026-10-27T21:20:21Z" }, { "t": "2026-10-28T08:57:37Z", "kind": "review_comment", "who": "hebasto", "assoc": "MEMBER", "path": "src/util/fs.cpp", "commit": "4451b0f6b2a73d5724ab64ebcddaaf2bcc4d0109", "in_reply_to": null, "text": "Unfortunately, the consecutive `fopen` and `fcntl(..., FD_CLOEXEC)` calls are not atomic, which is a race in a multithreaded process.", "id": "rc:4398624471", "url": "https://github.com/bitcoin/bitcoin/pull/36677#discussion_r4398624471", "hash": "34b8a206a0554208", "edited": null }, { "t": "2026-10-28T13:49:56Z", "kind": "review_comment", "who": "ValeraFinebits", "assoc": "NONE", "path": "src/util/fs.cpp", "commit": "c354037d4455e41ccf56705fa46187c4a3a09114", "in_reply_to": 4394300695, "text": "Could we keep the original `e` approach on Linux and handle macOS separately with `open` using `O_CLOEXEC`, followed by `fdopen`?", "id": "rc:4401375200", "url": "https://github.com/bitcoin/bitcoin/pull/36677#discussion_r4401375200", "hash": "0f9afbaa6e91aee2", "edited": null }, { "t": "2026-10-28T14:07:16Z", "kind": "comment", "who": "ValeraFinebits", "assoc": "NONE", "text": "I tested `fsbridge::fopen` at `ca864d2fc1` with a standalone MSVC test using `fs.cpp`. The file was opened in append mode (`\"a\"`), and handle inheritance was enabled in `CreateProcessW`. After the parent closed the file, `DeleteFileW` failed with `ERROR_SHARING_VIOLATION` on the pre-PR code. With this change, deletion succeeded while the child was still alive.\n\nThe compilation errors in `fs_tests.cpp` prevent `test_bitcoin` from building on Windows.", "id": "c:6471177983", "url": "https://github.com/bitcoin/bitcoin/pull/36677#issuecomment-6471177983", "hash": "8248860f8d96b8c9", "edited": null }, { "t": "2026-10-28T16:45:36Z", "kind": "review_comment", "who": "SirECMG", "assoc": "NONE", "path": "src/util/fs.cpp", "commit": "4451b0f6b2a73d5724ab64ebcddaaf2bcc4d0109", "in_reply_to": 4398624471, "text": "Yes, you are right, I will try to find a solution on how I can make it safe under multi threaded processes.", "id": "rc:4403445732", "url": "https://github.com/bitcoin/bitcoin/pull/36677#discussion_r4403445732", "hash": "f672ee642e85f71a", "edited": null }, { "t": "2026-10-28T18:26:42Z", "kind": "review_comment", "who": "SirECMG", "assoc": "NONE", "path": "src/util/fs.cpp", "commit": "c354037d4455e41ccf56705fa46187c4a3a09114", "in_reply_to": 4394300695, "text": "I changed implementation into three cases\n\n1. linux\n3. windows\n4. posix\n\n## references/docs\n- linux\n - https://man7.org/linux/man-pages/man3/freopen.3.html\n\n- windows\n - https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/fopen-wfopen?view=msvc-170\n\n- UNIX\n - https://www.flyriver.com/g/implement-file-handle-inheritance?auth=1793210997639", "id": "rc:4404499220", "url": "https://github.com/bitcoin/bitcoin/pull/36677#discussion_r4404499220", "hash": "319c39c45944a1cf", "edited": "2026-10-28T18:38:01Z" }, { "t": "2026-10-28T18:33:27Z", "kind": "review_comment", "who": "ValeraFinebits", "assoc": "NONE", "path": "src/util/fs.cpp", "commit": "9ebc30b17d67d12669babb06ad3549d68664cb97", "in_reply_to": null, "text": "```suggestion\n flags |= (read_write ? O_RDWR : O_WRONLY) | O_CREAT | O_TRUNC;\n```", "id": "rc:4404567090", "url": "https://github.com/bitcoin/bitcoin/pull/36677#discussion_r4404567090", "hash": "eafbb19ae4e8f327", "edited": "2026-10-28T18:37:06Z" }, { "t": "2026-10-28T18:34:23Z", "kind": "review_comment", "who": "ValeraFinebits", "assoc": "NONE", "path": "src/util/fs.cpp", "commit": "f2eac03b2eed5789c8ee5a4657588f535a5c3b04", "in_reply_to": null, "text": "```suggestion\n (void)::lseek(fd, 0, SEEK_END);\n```", "id": "rc:4404576433", "url": "https://github.com/bitcoin/bitcoin/pull/36677#discussion_r4404576433", "hash": "d7b224d51d95f6f7", "edited": "2026-10-28T18:37:06Z" }, { "t": "2026-10-28T18:35:43Z", "kind": "force_push", "who": "SirECMG", "commit": "9ebc30b17d67d12669babb06ad3549d68664cb97", "id": "push:9ebc30b17d67d12669babb06ad3549d68664cb97" }, { "t": "2026-10-28T18:37:06Z", "kind": "review", "who": "ValeraFinebits", "assoc": "NONE", "state": "COMMENTED", "commit": "bb15d682c5e153122f0b2151b679a195aeef9202", "text": "typos", "id": "r:5687773266", "url": "https://github.com/bitcoin/bitcoin/pull/36677#pullrequestreview-5687773266", "hash": "865c2d7a02ef557e", "edited": null }, { "t": "2026-10-28T18:40:00Z", "kind": "force_push", "who": "SirECMG", "commit": "f2eac03b2eed5789c8ee5a4657588f535a5c3b04", "id": "push:f2eac03b2eed5789c8ee5a4657588f535a5c3b04" }, { "t": "2026-10-28T18:42:04Z", "kind": "force_push", "who": "SirECMG", "commit": "30c974f601a9d4b1d987e0e8d0850faa839d38bb", "id": "push:30c974f601a9d4b1d987e0e8d0850faa839d38bb" }, { "t": "2026-10-28T18:44:25Z", "kind": "comment", "who": "SirECMG", "assoc": "NONE", "text": "Thanks @ValeraFinebits. I fixed the typos. Let me know what you think.", "id": "c:6477587666", "url": "https://github.com/bitcoin/bitcoin/pull/36677#issuecomment-6477587666", "hash": "37b703d069f42e3a", "edited": null }, { "t": "2026-10-28T18:49:41Z", "kind": "comment", "who": "ValeraFinebits", "assoc": "NONE", "text": "[quoted text omitted]\n\nCould we also add `` for `std::strchr`?", "id": "c:6477697524", "url": "https://github.com/bitcoin/bitcoin/pull/36677#issuecomment-6477697524", "hash": "a9946054b9ee2a39", "edited": "2026-10-28T18:52:29Z" }, { "t": "2026-10-28T18:59:17Z", "kind": "force_push", "who": "SirECMG", "commit": "f2875ebd401a6c8d0f03aaa39e46cf040a2953bf", "id": "push:f2875ebd401a6c8d0f03aaa39e46cf040a2953bf" }, { "t": "2026-10-28T19:03:12Z", "kind": "force_push", "who": "SirECMG", "commit": "e423eb6810bbffc72ecd3739b88ef5af86b012c3", "id": "push:e423eb6810bbffc72ecd3739b88ef5af86b012c3" }, { "t": "2026-10-28T19:05:05Z", "kind": "force_push", "who": "SirECMG", "commit": "55f35a25d390dad5c6182653df87edc1fc963f5b", "id": "push:55f35a25d390dad5c6182653df87edc1fc963f5b" }, { "t": "2026-10-28T19:06:57Z", "kind": "comment", "who": "SirECMG", "assoc": "NONE", "text": "Added the missing include!", "id": "c:6478095764", "url": "https://github.com/bitcoin/bitcoin/pull/36677#issuecomment-6478095764", "hash": "757b5c5871214b1c", "edited": "2026-10-28T19:07:44Z" }, { "t": "2026-10-28T20:30:43Z", "kind": "review", "who": "winterrdog", "assoc": "CONTRIBUTOR", "state": "COMMENTED", "commit": "0c9ab5633d89cd64c52b90ba27b198d10848f842", "text": "could you please squash your commits into two: _one for the unit test and one for the fix_ ?\n\nsee: https://github.com/bitcoin/bitcoin/blob/master/CONTRIBUTING.md#squashing-commits", "id": "r:5689284835", "url": "https://github.com/bitcoin/bitcoin/pull/36677#pullrequestreview-5689284835", "hash": "c2e019d2f217e98b", "edited": null }, { "t": "2026-10-28T21:07:23Z", "kind": "comment", "who": "ValeraFinebits", "assoc": "NONE", "text": "Tested on Windows at `0c9ab56`: the new test passes with the fix and fails on the `HANDLE_FLAG_INHERIT` check when I revert the Windows change in `fs.cpp`. Restoring the fix makes it pass again.", "id": "c:6480706270", "url": "https://github.com/bitcoin/bitcoin/pull/36677#issuecomment-6480706270", "hash": "dd65e58e134a95e7", "edited": null }, { "t": "2026-10-28T21:25:49Z", "kind": "force_push", "who": "SirECMG", "commit": "6a1ff77cfd71ceb9797b31d4545310163b7f4afa", "id": "push:6a1ff77cfd71ceb9797b31d4545310163b7f4afa" }, { "t": "2026-10-28T21:30:56Z", "kind": "comment", "who": "SirECMG", "assoc": "NONE", "text": "[quoted text omitted]\n\nI performed a squash to clean up the git history, as asked.", "id": "c:6481166654", "url": "https://github.com/bitcoin/bitcoin/pull/36677#issuecomment-6481166654", "hash": "fa280a61ac6d4106", "edited": null }, { "t": "2026-10-29T17:42:48Z", "kind": "force_push", "who": "SirECMG", "commit": "17ea8dd8185cc4ebcdb0b1fae2a0d892459e04c4", "id": "push:17ea8dd8185cc4ebcdb0b1fae2a0d892459e04c4" }, { "t": "2026-10-30T11:59:39Z", "kind": "comment", "who": "winterrdog", "assoc": "CONTRIBUTOR", "text": "seems like this fixes #36668. you can add `Fixes #36668` to the PR description to have it auto-close on merge", "id": "c:6522173210", "url": "https://github.com/bitcoin/bitcoin/pull/36677#issuecomment-6522173210", "hash": "95a6a294dd72650c", "edited": null } ], "labels_log": [ { "t": "2026-10-27T18:51:33Z", "action": "labeled", "label": "Utils/log/libs", "who": "DrahtBot" }, { "t": "2026-10-27T22:25:32Z", "action": "labeled", "label": "CI failed", "who": "DrahtBot" }, { "t": "2026-10-30T12:53:15Z", "action": "unlabeled", "label": "CI failed", "who": "DrahtBot" } ], "state_log": [], "text_chars": 2596, "text_tokens_estimate": 649, "changed_paths": [ "src/test/fs_tests.cpp", "src/util/fs.cpp" ], "files": [ { "path": "src/test/fs_tests.cpp", "add": 41, "del": 0 }, { "path": "src/util/fs.cpp", "add": 47, "del": 4 } ], "test_lines": 41, "git": { "head": "17ea8dd8185cc4ebcdb0b1fae2a0d892459e04c4", "head_matches_backup": true, "base": "23288073d4e7723bf7559a904bbf322a52d8af55", "patch_id": "b30bf17448865d02", "commits": [ { "sha": "082b385445", "subject": "util: Make fsbridge::fopen files non-inheritable", "files": 1, "add": 47, "del": 4 }, { "sha": "17ea8dd818", "subject": "test: Verify fsbridge::fopen opens non-inheritable files", "files": 1, "add": 41, "del": 0 } ], "patch_truncated": false }, "patch_id": "b30bf17448865d02", "input_hash": "ca68fe9ebb2f0ca0", "extracted_at": "2026-11-02T01:09:49+00:00" }