From 35253af01d8c0ab444c8377402121816e71c71f5 Mon Sep 17 00:00:00 2001 From: "djm@openbsd.org" Date: Wed, 18 Jan 2023 02:00:10 +0000 Subject: [PATCH] upstream: when restoring non-blocking mode to stdio fds, restore exactly the flags that ssh started with and don't just clobber them with zero, as this could also remove the append flag from the set; bz3523; ok dtucker@ OpenBSD-Commit-ID: 1336b03e881db7564a4b66014eb24c5230e9a0c0 --- channels.c | 19 ++++++++++++++----- channels.h | 3 ++- 2 files changed, 16 insertions(+), 6 deletions(-) diff --git a/channels.c b/channels.c index 981746ebd..0d26358cc 100644 --- a/channels.c +++ b/channels.c @@ -1,4 +1,4 @@ -/* $OpenBSD: channels.c,v 1.426 2023/01/06 02:47:18 djm Exp $ */ +/* $OpenBSD: channels.c,v 1.427 2023/01/18 02:00:10 djm Exp $ */ /* * Author: Tatu Ylonen * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland @@ -417,16 +417,19 @@ channel_register_fds(struct ssh *ssh, Channel *c, int rfd, int wfd, int efd, */ if (rfd != -1 && !isatty(rfd) && (val = fcntl(rfd, F_GETFL)) != -1 && !(val & O_NONBLOCK)) { + c->restore_flags[0] = val; c->restore_block |= CHANNEL_RESTORE_RFD; set_nonblock(rfd); } if (wfd != -1 && !isatty(wfd) && (val = fcntl(wfd, F_GETFL)) != -1 && !(val & O_NONBLOCK)) { + c->restore_flags[1] = val; c->restore_block |= CHANNEL_RESTORE_WFD; set_nonblock(wfd); } if (efd != -1 && !isatty(efd) && (val = fcntl(efd, F_GETFL)) != -1 && !(val & O_NONBLOCK)) { + c->restore_flags[2] = val; c->restore_block |= CHANNEL_RESTORE_EFD; set_nonblock(efd); } @@ -510,10 +513,16 @@ channel_close_fd(struct ssh *ssh, Channel *c, int *fdp) if (fd == -1) return 0; - if ((*fdp == c->rfd && (c->restore_block & CHANNEL_RESTORE_RFD) != 0) || - (*fdp == c->wfd && (c->restore_block & CHANNEL_RESTORE_WFD) != 0) || - (*fdp == c->efd && (c->restore_block & CHANNEL_RESTORE_EFD) != 0)) - (void)fcntl(*fdp, F_SETFL, 0); /* restore blocking */ + /* restore blocking */ + if (*fdp == c->rfd && + (c->restore_block & CHANNEL_RESTORE_RFD) != 0) + (void)fcntl(*fdp, F_SETFL, c->restore_flags[0]); + else if (*fdp == c->wfd && + (c->restore_block & CHANNEL_RESTORE_WFD) != 0) + (void)fcntl(*fdp, F_SETFL, c->restore_flags[1]); + else if (*fdp == c->efd && + (c->restore_block & CHANNEL_RESTORE_EFD) != 0) + (void)fcntl(*fdp, F_SETFL, c->restore_flags[2]); if (*fdp == c->rfd) { c->io_want &= ~SSH_CHAN_IO_RFD; diff --git a/channels.h b/channels.h index c80b55d0c..101843a06 100644 --- a/channels.h +++ b/channels.h @@ -1,4 +1,4 @@ -/* $OpenBSD: channels.h,v 1.147 2023/01/06 02:47:18 djm Exp $ */ +/* $OpenBSD: channels.h,v 1.148 2023/01/18 02:00:10 djm Exp $ */ /* * Author: Tatu Ylonen @@ -153,6 +153,7 @@ struct Channel { * this way post-IO handlers are not * accidentally called if a FD gets reused */ int restore_block; /* fd mask to restore blocking status */ + int restore_flags[3];/* flags to restore */ struct sshbuf *input; /* data read from socket, to be sent over * encrypted connection */ struct sshbuf *output; /* data received over encrypted connection for