On Sun, Nov 15, 2020 at 05:34:16PM -0700, Nathan Chancellor wrote: > Still good. > > Tested-by: Nathan Chancellor <natechancellor@xxxxxxxxx> Pushed into #fixes > > BTW, is that call of readv() really coming from init? And if it > > is, what version of init are you using? > > I believe that it is but since this is WSL2, I believe that /init is a > proprietary Microsoft implementation, rather than systemd or another > init system: > > https://wiki.ubuntu.com/WSL#Keeping_Ubuntu_Updated_in_WSL > > So I am not sure how possible it is to see exactly what is going on or > getting it improved. Oh, well... Anyway, as a regression test it's interesting: #include <sys/uio.h> #include <unistd.h> #include <stdio.h> #include <errno.h> main() { static char s[1024]; static struct iovec v[2] = {{NULL, 0}, {s, 1024}}; for(;;) { ssize_t n = readv(0, v, 2), m, w; if (n < 0) { perror("readv"); return -1; } if (!n) return 0; for (m = 0; m < n; m += w) { w = write(1, s + m, n - m); if (w < 0) perror("write"); } } } which ought to copy stdin to stdout; with this bug it would (on sufficiently large seq_file-based files) fail with "readv: Bad address" (-EFAULT, that is).
