linux-toradex.git/drivers/tty/n_hdlc.c, branch v4.19-rc4

vfs: do bulk POLL* -> EPOLL* replacement

2018-02-11T22:34:03+00:00

This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:

    for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
        L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
        for f in $L; do sed -i "-es/^\([^\"]*\)\(\\)/\\1E\\2/" $f; done
    done

with de-mangling cleanups yet to come.

NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do.  But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.

The next patch from Al will sort out the final differences, and we
should be all done.

Scripted-by: Al Viro 
Signed-off-by: Linus Torvalds

the rest of drivers/*: annotate ->poll() instances

2017-11-28T16:06:58+00:00

Signed-off-by: Al Viro

tty: Remove redundant license text

2017-11-08T12:08:12+00:00

Now that the SPDX tag is in all tty files, that identifies the license
in a specific and legally-defined manner.  So the extra GPL text wording
can be removed as it is no longer needed at all.

This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text.  And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.

No copyright headers or other non-license-description text was removed.

Cc: Jiri Slaby 
Cc: James Hogan 
Signed-off-by: Greg Kroah-Hartman

tty: add SPDX identifiers to all remaining files in drivers/tty/

2017-11-08T12:08:12+00:00

It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the drivers/tty files files with the correct SPDX license
identifier based on the license text in the file itself.  The SPDX
identifier is a legally binding shorthand, which can be used instead of
the full boiler plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Jiri Slaby 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Michael Ellerman 
Cc: Chris Metcalf 
Cc: Jiri Kosina 
Cc: David Sterba 
Cc: James Hogan 
Cc: Rob Herring 
Cc: Eric Anholt 
Cc: Stefan Wahren 
Cc: Florian Fainelli 
Cc: Ray Jui 
Cc: Scott Branden 
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: "James E.J. Bottomley" 
Cc: Helge Deller 
Cc: Joachim Eastwood 
Cc: Matthias Brugger 
Cc: Masahiro Yamada 
Cc: Tobias Klauser 
Cc: Russell King 
Cc: Vineet Gupta 
Cc: Richard Genoud 
Cc: Alexander Shiyan 
Cc: Baruch Siach 
Cc: "Maciej W. Rozycki" 
Cc: "Uwe Kleine-König" 
Cc: Pat Gefre 
Cc: "Guilherme G. Piccoli" 
Cc: Jason Wessel 
Cc: Vladimir Zapolskiy 
Cc: Sylvain Lemieux 
Cc: Carlo Caione 
Cc: Kevin Hilman 
Cc: Liviu Dudau 
Cc: Sudeep Holla 
Cc: Lorenzo Pieralisi 
Cc: Andy Gross 
Cc: David Brown 
Cc: "Andreas Färber" 
Cc: Kevin Cernekee 
Cc: Laxman Dewangan 
Cc: Thierry Reding 
Cc: Jonathan Hunter 
Cc: Barry Song 
Cc: Patrice Chotard 
Cc: Maxime Coquelin 
Cc: Alexandre Torgue 
Cc: "David S. Miller" 
Cc: Peter Korsgaard 
Cc: Timur Tabi 
Cc: Tony Prisk 
Cc: Michal Simek 
Cc: "Sören Brinkmann" 
Cc: Thomas Gleixner 
Cc: Kate Stewart 
Cc: Philippe Ombredanne 
Cc: Jiri Slaby 
Signed-off-by: Greg Kroah-Hartman

format-security: move static strings to const

2017-05-09T00:15:14+00:00

While examining output from trial builds with -Wformat-security enabled,
many strings were found that should be defined as "const", or as a char
array instead of char pointer.  This makes some static analysis easier,
by producing fewer false positives.

As these are all trivial changes, it seemed best to put them all in a
single patch rather than chopping them up per maintainer.

Link: http://lkml.kernel.org/r/20170405214711.GA5711@beast
Signed-off-by: Kees Cook 
Acked-by: Jes Sorensen 	[runner.c]
Cc: Tony Lindgren 
Cc: Russell King 
Cc: "Maciej W. Rozycki" 
Cc: Ralf Baechle 
Cc: Arnd Bergmann 
Cc: Greg Kroah-Hartman 
Cc: "Rafael J. Wysocki" 
Cc: Viresh Kumar 
Cc: Daniel Vetter 
Cc: Jani Nikula 
Cc: Sean Paul 
Cc: David Airlie 
Cc: Yisen Zhuang 
Cc: Salil Mehta 
Cc: Thomas Bogendoerfer 
Cc: Jiri Slaby 
Cc: Patrice Chotard 
Cc: "David S. Miller" 
Cc: James Hogan 
Cc: Paul Burton 
Cc: Matt Redfearn 
Cc: Paolo Bonzini 
Cc: Ingo Molnar 
Cc: Rasmus Villemoes 
Cc: Mugunthan V N 
Cc: Felipe Balbi 
Cc: Jarod Wilson 
Cc: Florian Westphal 
Cc: Antonio Quartulli 
Cc: Dmitry Torokhov 
Cc: Kejian Yan 
Cc: Daode Huang 
Cc: Qianqian Xie 
Cc: Philippe Reynes 
Cc: Colin Ian King 
Cc: Eric Dumazet 
Cc: Christian Gromm 
Cc: Andrey Shvetsov 
Cc: Jason Litzinger 
Cc: WANG Cong 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

tty: n_hdlc: get rid of racy n_hdlc.tbuf

2017-03-07T17:54:30+00:00

Currently N_HDLC line discipline uses a self-made singly linked list for
data buffers and has n_hdlc.tbuf pointer for buffer retransmitting after
an error.

The commit be10eb7589337e5defbe214dae038a53dd21add8
("tty: n_hdlc add buffer flushing") introduced racy access to n_hdlc.tbuf.
After tx error concurrent flush_tx_queue() and n_hdlc_send_frames() can put
one data buffer to tx_free_buf_list twice. That causes double free in
n_hdlc_release().

Let's use standard kernel linked list and get rid of n_hdlc.tbuf:
in case of tx error put current data buffer after the head of tx_buf_list.

Signed-off-by: Alexander Popov 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

lib/vsprintf.c: remove %Z support

2017-02-28T02:43:47+00:00

Now that %z is standartised in C99 there is no reason to support %Z.
Unlike %L it doesn't even make format strings smaller.

Use BUILD_BUG_ON in a couple ATM drivers.

In case anyone didn't notice lib/vsprintf.o is about half of SLUB which
is in my opinion is quite an achievement.  Hopefully this patch inspires
someone else to trim vsprintf.c more.

Link: http://lkml.kernel.org/r/20170103230126.GA30170@avx2
Signed-off-by: Alexey Dobriyan 
Cc: Andy Shevchenko 
Cc: Rasmus Villemoes 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Replace with globally

2016-12-24T19:46:01+00:00

This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*'
  sed -i -e "s!$PATT!#include !" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro 
Signed-off-by: Linus Torvalds

Fix OpenSSH pty regression on close

2016-05-01T20:22:54+00:00

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) f8747d4a466ab2cafe56112c51b3379f9fdb7a12
   tty: Fix pty master read() after slave closes

2) 52bce7f8d4fc633c9a9d0646eef58ba6ae9a3b73
   pty, n_tty: Simplify input processing on final close

3) 1a48632ffed61352a7810ce089dc5a8bcd505a60
   pty: Fix input race when closing

Inspired by analysis and patch from Marc Aurele La France 

Reported-by: Volth 
Reported-by: Marc Aurele La France 
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 
Reviewed-by: Peter Hurley 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

TTY: n_hdlc, fix lockdep false positive

2016-02-07T07:27:46+00:00

The class of 4 n_hdls buf locks is the same because a single function
n_hdlc_buf_list_init is used to init all the locks. But since
flush_tx_queue takes n_hdlc->tx_buf_list.spinlock and then calls
n_hdlc_buf_put which takes n_hdlc->tx_free_buf_list.spinlock, lockdep
emits a warning:
=============================================
[ INFO: possible recursive locking detected ]
4.3.0-25.g91e30a7-default #1 Not tainted
---------------------------------------------
a.out/1248 is trying to acquire lock:
 (&(&list->spinlock)->rlock){......}, at: [] n_hdlc_buf_put+0x20/0x60 [n_hdlc]

but task is already holding lock:
 (&(&list->spinlock)->rlock){......}, at: [] n_hdlc_tty_ioctl+0x127/0x1d0 [n_hdlc]

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&(&list->spinlock)->rlock);
  lock(&(&list->spinlock)->rlock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

2 locks held by a.out/1248:
 #0:  (&tty->ldisc_sem){++++++}, at: [] tty_ldisc_ref_wait+0x20/0x50
 #1:  (&(&list->spinlock)->rlock){......}, at: [] n_hdlc_tty_ioctl+0x127/0x1d0 [n_hdlc]
...
Call Trace:
...
 [] _raw_spin_lock_irqsave+0x50/0x70
 [] n_hdlc_buf_put+0x20/0x60 [n_hdlc]
 [] n_hdlc_tty_ioctl+0x144/0x1d0 [n_hdlc]
 [] tty_ioctl+0x3f1/0xe40
...

Fix it by initializing the spin_locks separately. This removes also
reduntand memset of a freshly kzallocated space.

Signed-off-by: Jiri Slaby 
Reported-by: Dmitry Vyukov 
Signed-off-by: Greg Kroah-Hartman