public inbox for cygwin-cvs@sourceware.org
help / color / mirror / Atom feed
* [newlib-cygwin/cygwin-3_3-branch] Cygwin: console: Avoid accessing NULL pointer via cygheap->ctty.
@ 2022-07-29 13:00 Takashi Yano
0 siblings, 0 replies; only message in thread
From: Takashi Yano @ 2022-07-29 13:00 UTC (permalink / raw)
To: cygwin-cvs
https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=69ec3976d609cfebe9acbca34015ece6b6bd4995
commit 69ec3976d609cfebe9acbca34015ece6b6bd4995
Author: Takashi Yano <takashi.yano@nifty.ne.jp>
Date: Fri Jul 29 21:40:18 2022 +0900
Cygwin: console: Avoid accessing NULL pointer via cygheap->ctty.
- Recent commit "Cygwin: console: Add missing input_mutex guard."
has a problem that causes NULL pointer access if cygheap->ctty
is NULL. This patch fixes the issue.
Diff:
---
winsup/cygwin/fhandler.h | 2 +-
winsup/cygwin/fhandler_console.cc | 22 ++++++++++++++--------
2 files changed, 15 insertions(+), 9 deletions(-)
diff --git a/winsup/cygwin/fhandler.h b/winsup/cygwin/fhandler.h
index e47b38e9a..da0e3183e 100644
--- a/winsup/cygwin/fhandler.h
+++ b/winsup/cygwin/fhandler.h
@@ -2294,7 +2294,7 @@ private:
static void cleanup_for_non_cygwin_app (handle_set_t *p);
static void set_console_mode_to_native ();
bool need_console_handler ();
- static void set_disable_master_thread (bool x);
+ static void set_disable_master_thread (bool x, fhandler_console *cons = NULL);
friend tty_min * tty_list::get_cttyp ();
};
diff --git a/winsup/cygwin/fhandler_console.cc b/winsup/cygwin/fhandler_console.cc
index c7dc8c609..41b3fd6b8 100644
--- a/winsup/cygwin/fhandler_console.cc
+++ b/winsup/cygwin/fhandler_console.cc
@@ -790,7 +790,7 @@ fhandler_console::setup_for_non_cygwin_app ()
(get_ttyp ()->getpgid ()== myself->pgid) ? tty::native : tty::restore;
set_input_mode (conmode, &tc ()->ti, get_handle_set ());
set_output_mode (conmode, &tc ()->ti, get_handle_set ());
- set_disable_master_thread (true);
+ set_disable_master_thread (true, this);
}
void
@@ -984,7 +984,7 @@ fhandler_console::bg_check (int sig, bool dontsignal)
if (sig == SIGTTIN)
{
set_input_mode (tty::cygwin, &tc ()->ti, get_handle_set ());
- set_disable_master_thread (false);
+ set_disable_master_thread (false, this);
}
if (sig == SIGTTOU)
set_output_mode (tty::cygwin, &tc ()->ti, get_handle_set ());
@@ -1723,7 +1723,7 @@ fhandler_console::post_open_setup (int fd)
if (fd == 0)
{
set_input_mode (tty::cygwin, &get_ttyp ()->ti, &handle_set);
- set_disable_master_thread (false);
+ set_disable_master_thread (false, this);
}
else if (fd == 1 || fd == 2)
set_output_mode (tty::cygwin, &get_ttyp ()->ti, &handle_set);
@@ -1751,7 +1751,7 @@ fhandler_console::close ()
/* Cleaning-up console mode for cygwin apps. */
set_output_mode (tty::restore, &get_ttyp ()->ti, &handle_set);
set_input_mode (tty::restore, &get_ttyp ()->ti, &handle_set);
- set_disable_master_thread (true);
+ set_disable_master_thread (true, this);
}
}
@@ -3977,7 +3977,7 @@ fhandler_console::set_console_mode_to_native ()
termios *cons_ti = &cons->tc ()->ti;
set_input_mode (tty::native, cons_ti, cons->get_handle_set ());
set_output_mode (tty::native, cons_ti, cons->get_handle_set ());
- set_disable_master_thread (true);
+ set_disable_master_thread (true, cons);
break;
}
}
@@ -4357,11 +4357,17 @@ fhandler_console::need_console_handler ()
}
void
-fhandler_console::set_disable_master_thread (bool x)
+fhandler_console::set_disable_master_thread (bool x, fhandler_console *cons)
{
- if (cygheap->ctty->get_major () != DEV_CONS_MAJOR)
+ if (con.disable_master_thread == x)
return;
- fhandler_console *cons = (fhandler_console *) cygheap->ctty;
+ if (cons == NULL)
+ {
+ if (cygheap->ctty && cygheap->ctty->get_major () == DEV_CONS_MAJOR)
+ cons = (fhandler_console *) cygheap->ctty;
+ else
+ return;
+ }
cons->acquire_input_mutex (mutex_timeout);
con.disable_master_thread = x;
cons->release_input_mutex ();
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2022-07-29 13:00 UTC | newest]
Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-07-29 13:00 [newlib-cygwin/cygwin-3_3-branch] Cygwin: console: Avoid accessing NULL pointer via cygheap->ctty Takashi Yano
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).