Great, committed, thanks

On Wed, Feb 08, 2017 at 10:46:43AM -0600, attila wrote:
> 
> Nicholas Marriott <[email protected]> writes:
> 
> > Yes, it is no longer OK for window_copy_pagedown to reset copy mode, it
> > needs to let the caller do it (because there is stuff to free, and it
> > can only know it needs to free it by dereferencing the mode data). I
> > changed the rest and missed this one.
> >
> > Try this please:
> 
> This fixes it.
> 
> Thanks for looking into it.
> 
> Pax, -A
> 
> > Index: window-copy.c
> > ===================================================================
> > RCS file: /cvs/src/usr.bin/tmux/window-copy.c,v
> > retrieving revision 1.165
> > diff -u -p -r1.165 window-copy.c
> > --- window-copy.c   3 Feb 2017 11:57:28 -0000       1.165
> > +++ window-copy.c   8 Feb 2017 11:17:06 -0000
> > @@ -29,7 +29,7 @@ static void       window_copy_command(struct w
> >                 struct session *, struct args *, struct mouse_event *);
> >  static struct screen *window_copy_init(struct window_pane *);
> >  static void        window_copy_free(struct window_pane *);
> > -static void        window_copy_pagedown(struct window_pane *, int);
> > +static int window_copy_pagedown(struct window_pane *, int);
> >  static void        window_copy_next_paragraph(struct window_pane *);
> >  static void        window_copy_previous_paragraph(struct window_pane *);
> >  static void        window_copy_resize(struct window_pane *, u_int, u_int);
> > @@ -380,7 +380,7 @@ window_copy_pageup(struct window_pane *w
> >     window_copy_redraw_screen(wp);
> >  }
> >
> > -static void
> > +static int
> >  window_copy_pagedown(struct window_pane *wp, int half_page)
> >  {
> >     struct window_copy_mode_data    *data = wp->modedata;
> > @@ -420,13 +420,11 @@ window_copy_pagedown(struct window_pane
> >                     window_copy_cursor_end_of_line(wp);
> >     }
> >
> > -   if (data->scroll_exit && data->oy == 0) {
> > -           window_pane_reset_mode(wp);
> > -           return;
> > -   }
> > -
> > +   if (data->scroll_exit && data->oy == 0)
> > +           return (1);
> >     window_copy_update_selection(wp, 1);
> >     window_copy_redraw_screen(wp);
> > +   return (0);
> >  }
> >
> >  static void
> > @@ -621,8 +619,12 @@ window_copy_command(struct window_pane *
> >             if (strcmp(command, "end-of-line") == 0)
> >                     window_copy_cursor_end_of_line(wp);
> >             if (strcmp(command, "halfpage-down") == 0) {
> > -                   for (; np != 0; np--)
> > -                           window_copy_pagedown(wp, 1);
> > +                   for (; np != 0; np--) {
> > +                           if (window_copy_pagedown(wp, 1)) {
> > +                                   cancel = 1;
> > +                                   break;
> > +                           }
> > +                   }
> >             }
> >             if (strcmp(command, "halfpage-up") == 0) {
> >                     for (; np != 0; np--)
> > @@ -715,8 +717,12 @@ window_copy_command(struct window_pane *
> >                             window_copy_other_end(wp);
> >             }
> >             if (strcmp(command, "page-down") == 0) {
> > -                   for (; np != 0; np--)
> > -                           window_copy_pagedown(wp, 0);
> > +                   for (; np != 0; np--) {
> > +                           if (window_copy_pagedown(wp, 0)) {
> > +                                   cancel = 1;
> > +                                   break;
> > +                           }
> > +                   }
> >             }
> >             if (strcmp(command, "page-up") == 0) {
> >                     for (; np != 0; np--)
> >
> >
> >
> >
> > On Wed, Feb 08, 2017 at 06:56:55AM +0100, Otto Moerbeek wrote:
> >> On Tue, Feb 07, 2017 at 10:59:00AM -0600, attila wrote:
> >>
> >> >
> >> > [email protected] writes:
> >> >
> >> > >>Synopsis:      tmux can be made to dump core when a certain bind-key 
> >> > >>option is present
> >> > >>Category:      system
> >> > >>Environment:
> >> > >        System      : OpenBSD 6.0
> >> > >        Details     : OpenBSD 6.0-current (GENERIC.MP) #158: Mon Jan 30 
> >> > > 19:30:12 MST 2017
> >> > >                         
> >> > > [email protected]:/usr/src/sys/arch/amd64/compile/GENERIC.MP
> >> > >
> >> > >        Architecture: OpenBSD.amd64
> >> > >        Machine     : amd64
> >> > >>Description:
> >> > >
> >> > > When in a tmux session hitting the command prefix key + PgUp and PgDn
> >> > > immediately afterwards causes a core dump if a certain bind-key option
> >> > > is present.  The backtrace is not useful (/etc/malloc.conf -> CFGJU).
> >> > >
> >> > > This bind-key is not necessary as far as I can tell, since the default
> >> > > behavior of recent tmux seems to be what that bind-key intends to do
> >> > > (enter copy mode when C-b PageUp is pressed).  I don't know how I had
> >> > > it in my ~/.tmux.conf, but commenting it out stops the core dump.
> >> > >
> >> > >>How-To-Repeat:
> >> > > (1) tmux with the default configuration (mv away your ~/.tmux.conf
> >> > >     or touch nonexistent_file && tmux -f nonexistent_file)
> >> > > (2) Hit C-b : bind-key PageUp copy-mode -eu
> >> > > (3) Hit C-b PageUp PageDown
> >> >
> >> > Here is a backtrace from this snap:
> >> >
> >> > OpenBSD 6.0-current (GENERIC.MP) #163: Sun Feb  5 13:55:12 MST 2017
> >> >     [email protected]:/usr/src/sys/arch/amd64/compile/GENERIC.MP
> >> >
> >> >
> >> > (gdb) bt
> >> > #0  0x0000075cf82507aa in thrkill () at <stdin>:2
> >> > #1  0x0000075cf828f749 in *_libc_abort () at 
> >> > /usr/src/lib/libc/stdlib/abort.c:52
> >> > #2  0x0000075cf8230012 in wrterror (d=Variable "d" is not available.
> >> > ) at /usr/src/lib/libc/stdlib/malloc.c:303
> >> > #3  0x0000075cf8231284 in ofree (argpool=0x75c37135ca0, 
> >> > p=0xdfdfdfdfdfdfdfdf)
> >> >     at /usr/src/lib/libc/stdlib/malloc.c:1374
> >> > #4  0x0000075cf82314eb in free (ptr=0xdfdfdfdfdfdfdfdf) at 
> >> > /usr/src/lib/libc/stdlib/malloc.c:1407
> >> > #5  0x0000075a03942208 in tty_cmd_clearcharacter () from /usr/bin/tmux
> >> > #6  0x0000075a039453c8 in tty_cmd_clearcharacter () from /usr/bin/tmux
> >> > #7  0x0000075a0390cb02 in ?? () from /usr/bin/tmux
> >> > #8  0x0000075a03914ab2 in ?? () from /usr/bin/tmux
> >> > #9  0x0000075a03932cf0 in control_callback () from /usr/bin/tmux
> >> > #10 0x0000075a03929908 in control_callback () from /usr/bin/tmux
> >> > #11 0x0000075a03932c8a in control_callback () from /usr/bin/tmux
> >> > #12 0x0000075a039038f4 in ?? () from /usr/bin/tmux
> >> > #13 0x0000075a03939bdf in control_callback () from /usr/bin/tmux
> >> > #14 0x0000075a03900f6e in ?? () from /usr/bin/tmux
> >> > #15 0x0000000000000000 in ?? ()
> >>
> >> Hi,
> >>
> >> I took a look because I wanted to know if this is falloout from recent
> >> malloc changes.
> >>
> >> Compiled with -O0 -g I get a slightly different stacktrace, see
> >> below. This does look like a genuine user-after-free. Probably nicm@
> >> can spot the bug easier than me so I included him in the To:.
> >>
> >>    -Otto
> >>
> >> #4  0x00001f49066e6c4b in free (ptr=0xdfdfdfdfdfdfdfdf)
> >>     at /usr/src/lib/libc/stdlib/malloc.c:1407
> >> #5  0x00001f46dad5c3f5 in window_copy_clear_marks (wp=0x1f49501b1800)
> >>     at /usr/src/usr.bin/tmux/window-copy.c:1212
> >> #6  0x00001f46dad5b7b9 in window_copy_command (wp=0x1f49501b1800,
> >>     c=0x1f49d6363800, s=0x1f4902252200, args=0x1f4904f00ca0, m=0x0)
> >>     at /usr/src/usr.bin/tmux/window-copy.c:920
> >> #7  0x00001f46dad0fe98 in cmd_send_keys_exec (self=0x1f49b7a42780,
> >>     item=0x1f4904f03a00) at /usr/src/usr.bin/tmux/cmd-send-keys.c:90
> >> #8  0x00001f46dad1a995 in cmdq_fire_command (item=0x1f4904f03a00)
> >>     at /usr/src/usr.bin/tmux/cmd-queue.c:203
> >> #9  0x00001f46dad1ae7d in cmdq_next (c=0x1f49d6363800)
> >>     at /usr/src/usr.bin/tmux/cmd-queue.c:325
> >> #10 0x00001f46dad454a8 in server_loop () at 
> >> /usr/src/usr.bin/tmux/server.c:198
> >> #11 0x00001f46dad392b1 in proc_loop (tp=0x1f48edc832c0,
> >>     loopcb=0x1f46dad45467 <server_loop>) at 
> >> /usr/src/usr.bin/tmux/proc.c:220
> >> #12 0x00001f46dad4543a in server_start (base=0x1f4924ac5c00, lockfd=8,
> >>     lockfile=0x1f49270bc120 "10.1.1.4 55392 10.1.1.3 22")
> >>     at /usr/src/usr.bin/tmux/server.c:182
> >> #13 0x00001f46dad0463b in client_connect (base=0x1f4924ac5c00,
> >>     path=0x1f49594a5460 "/tmp/tmux-1000/default", start_server=1)
> >>     at /usr/src/usr.bin/tmux/client.c:160
> >> #14 0x00001f46dad0498c in client_main (base=0x1f4924ac5c00, argc=0,
> >>     argv=0x7f7ffffc5ff0, flags=0, shellcmd=0x0)
> >>     at /usr/src/usr.bin/tmux/client.c:268
> >> #15 0x00001f46dad4ef8b in main (argc=0, argv=0x7f7ffffc5ff0)
> >>     at /usr/src/usr.bin/tmux/tmux.c:349
> --
> https://haqistan.net/~attila | attila@{stalphonsos.com,haqistan.net}
> pgp: 0x62A729CF | C2CE 2487 03AC 4C2F 101D  09C1 4068 D5D5 62A7 29CF

Reply via email to