sudo/backport-Reinstall-the-event-handler-if-we-get-EAGAIN-from-re.patch
zhoushuiqing 5ee298be21 Backport patches form upstream community
(cherry picked from commit 23b42da498fb65fe2292ea1858ee0fe64ff57e03)
2023-06-13 14:28:09 +08:00

62 lines
1.8 KiB
Diff

From c2a131714a6b9eccba7779bde64ce79a0377b541 Mon Sep 17 00:00:00 2001
From: "Todd C. Miller" <Todd.Miller@sudo.ws>
Date: Mon, 6 Jun 2022 19:42:07 -0600
Subject: [PATCH] Reinstall the event handler if we get EAGAIN from read/write
callback. The read and write events do not set SUDO_EV_PERSIST so we need to
explicitly re-enable the event if there is still data to be read. Bug #963.
---
src/exec_pty.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/src/exec_pty.c b/src/exec_pty.c
index 326d8318a..d2fc1ce5c 100644
--- a/src/exec_pty.c
+++ b/src/exec_pty.c
@@ -676,8 +676,12 @@ read_callback(int fd, int what, void *v)
/* Schedule SIGTTIN to be forwarded to the command. */
schedule_signal(iob->ec, SIGTTIN);
}
- if (errno == EAGAIN || errno == EINTR)
+ if (errno == EAGAIN || errno == EINTR) {
+ /* Re-enable reader. */
+ if (sudo_ev_add(evbase, iob->revent, NULL, false) == -1)
+ sudo_fatal("%s", U_("unable to add event to queue"));
break;
+ }
/* treat read error as fatal and close the fd */
sudo_debug_printf(SUDO_DEBUG_ERROR,
"error reading fd %d: %s", fd, strerror(errno));
@@ -717,6 +721,8 @@ read_callback(int fd, int what, void *v)
}
break;
}
+
+ debug_return;
}
/*
@@ -783,7 +789,9 @@ write_callback(int fd, int what, void *v)
}
FALLTHROUGH;
case EAGAIN:
- /* not an error */
+ /* Not an error, re-enable writer. */
+ if (sudo_ev_add(evbase, iob->wevent, NULL, false) == -1)
+ sudo_fatal("%s", U_("unable to add event to queue"));
break;
default:
/* XXX - need a way to distinguish non-exec error. */
@@ -821,6 +829,8 @@ write_callback(int fd, int what, void *v)
}
}
}
+
+ debug_return;
}
static void
--
2.33.0