diff options
| author | Takashi Yano <takashi.yano@nifty.ne.jp> | 2020-02-25 01:12:16 +0900 |
|---|---|---|
| committer | Corinna Vinschen <corinna@vinschen.de> | 2020-02-24 19:41:16 +0100 |
| commit | 17528b9d2c3147f5de0f604fc2702b2e0010c533 (patch) | |
| tree | 70ef05e36ceb590b65817189abc5f6d27b1162a5 | |
| parent | 86f9ce97bc4dd8dd14757157ae944c2c678d62a9 (diff) | |
| download | cygnal-17528b9d2c3147f5de0f604fc2702b2e0010c533.tar.gz cygnal-17528b9d2c3147f5de0f604fc2702b2e0010c533.tar.bz2 cygnal-17528b9d2c3147f5de0f604fc2702b2e0010c533.zip | |
Cygwin: console: Fix segfault on shared_console_info access.
- Accessing shared_console_info before initialization causes access
violation because it is a NULL pointer. The cause of the problem
reported in https://cygwin.com/ml/cygwin/2020-02/msg00197.html is
this NULL pointer access in request_xterm_mode_output() when it is
called from close(). This patch makes sure that shared_console_info
is not NULL before calling request_xterm_mode_output().
| -rw-r--r-- | winsup/cygwin/fhandler_console.cc | 23 | ||||
| -rw-r--r-- | winsup/cygwin/release/3.1.5 | 4 |
2 files changed, 15 insertions, 12 deletions
diff --git a/winsup/cygwin/fhandler_console.cc b/winsup/cygwin/fhandler_console.cc index 42040a971..328424a7d 100644 --- a/winsup/cygwin/fhandler_console.cc +++ b/winsup/cygwin/fhandler_console.cc @@ -1159,18 +1159,17 @@ fhandler_console::close () acquire_output_mutex (INFINITE); - if (shared_console_info && myself->pid == con.owner && - wincap.has_con_24bit_colors () && !con_is_legacy) - request_xterm_mode_output (false); - - /* Restore console mode if this is the last closure. */ - OBJECT_BASIC_INFORMATION obi; - NTSTATUS status; - status = NtQueryObject (get_handle (), ObjectBasicInformation, - &obi, sizeof obi, NULL); - if (NT_SUCCESS (status) && obi.HandleCount == 1) - if (wincap.has_con_24bit_colors ()) - request_xterm_mode_output (false); + if (shared_console_info && wincap.has_con_24bit_colors ()) + { + /* Restore console mode if this is the last closure. */ + OBJECT_BASIC_INFORMATION obi; + NTSTATUS status; + status = NtQueryObject (get_handle (), ObjectBasicInformation, + &obi, sizeof obi, NULL); + if ((NT_SUCCESS (status) && obi.HandleCount == 1) + || myself->pid == con.owner) + request_xterm_mode_output (false); + } release_output_mutex (); diff --git a/winsup/cygwin/release/3.1.5 b/winsup/cygwin/release/3.1.5 index 796fd2126..e34fdb88d 100644 --- a/winsup/cygwin/release/3.1.5 +++ b/winsup/cygwin/release/3.1.5 @@ -5,3 +5,7 @@ Bug Fixes: Don't move cursor to the right in case of a NUL character in the console output stream, this is not backed by terminfo. Addresses: https://cygwin.com/ml/cygwin/2020-02/msg00162.html + +- Fix a segfault when starting, e.g., mintty from a bash in a console + running xterm emulation. + Addresses: https://cygwin.com/ml/cygwin/2020-02/msg00197.html |