[christianaurichzm]

fs.readFile() and fs.promises.readFile() ignore an AbortSignal on FIFOs and devices. The read only ends at EOF, so on a FIFO whose writer stays open the abort waits for the writer to close, and on /dev/zero it never ends:

const ac = new AbortController();
setTimeout(() => ac.abort(), 100);
require('fs').promises.readFile('/dev/zero', { signal: ac.signal })
  .catch((err) => console.log(err.name));

v22.23.1 prints AbortError after 100 ms. On main it never does, and memory grows until the process is killed (after 1 s with a 2 GiB limit).

Since #65327, ReadFileJob reads a non-regular file to EOF in one thread pool job and only checks the signal when the job is done. Files over one chunk already go back to the chunked reader, which checks it before each read. Send non-regular files there as well. Regular files that report size 0, like the ones in procfs, are still read in one job. Only v26.8.0+ is affected.

The new test aborts a read on a FIFO and checks that the reader closes it while the writer is still open. It fails on main for both APIs and passes with the fix. fs tests, C++ lint/format and ESLint pass on Linux x64.

Refs: #65327

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.59%. Comparing base (44d5d57) to head (10ebd2a).
⚠️ Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #66940      +/-   ##
==========================================
+ Coverage   90.57%   90.59%   +0.01%     
==========================================
  Files         797      797              
  Lines      278502   278278     -224     
  Branches    53538    53504      -34     
==========================================
- Hits       252267   252106     -161     
+ Misses      16576    16542      -34     
+ Partials     9659     9630      -29     

Files with missing lines	Coverage Δ
lib/fs.js	97.17% <100.00%> (+<0.01%)	⬆️
lib/internal/fs/promises.js	91.63% <100.00%> (+0.41%)	⬆️
src/node_file.cc	75.69% <100.00%> (-0.20%)	⬇️

... and 31 files with indirect coverage changes

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