xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Fix OpenSSH pty regression on close

Browse Source 
OpenSSH expects the (non-blocking) read() of pty master to return
EAGAIN only if it has received all of the slave-side output after
it has received SIGCHLD. This used to work on pre-3.12 kernels.

This fix effectively forces non-blocking read() and poll() to
block for parallel i/o to complete for all ttys. It also unwinds
these changes:

1) f8747d4a46
   tty: Fix pty master read() after slave closes

2) 52bce7f8d4
   pty, n_tty: Simplify input processing on final close

3) 1a48632ffe
   pty: Fix input race when closing

Inspired by analysis and patch from Marc Aurele La France <tsi@tuyoix.net>

Reported-by: Volth <openssh@volth.com>
Reported-by: Marc Aurele La France <tsi@tuyoix.net>
BugLink: https://bugzilla.mindrot.org/show_bug.cgi?id=52
BugLink: https://bugzilla.mindrot.org/show_bug.cgi?id=2492
Signed-off-by: Brian Bloniarz <brian.bloniarz@gmail.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Brian Bloniarz
2016-03-06 13:16:30 -08:00
committed by Greg Kroah-Hartman
parent d11df61853
commit 0f40fbbcc3
6 changed files with 44 additions and 75 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
Documentation/serial/tty.txt
View File

@@ -210,9 +210,6 @@ TTY_IO_ERROR If set, causes all subsequent userspace read/write
TTY_OTHER_CLOSED Device is a pty and the other side has closed.
TTY_OTHER_DONE Device is a pty and the other side has closed and
all pending input processing has been completed.
TTY_NO_WRITE_SPLIT Prevent driver from splitting up writes into
smaller chunks.