This change tracks, for each wlr_seat_client, the most recent serial
numbers which were sent to the client. When the client makes a
selection request, wlroots now verifies that the serial number
associated with the selection request was actually provided to that
specific client. This ensures that the client that was most
recently interacted with always has priority for its copy selection
requests, and that no other clients can incorrectly use a larger serial
value and "steal" the role of having the copy selection.
Also, the code used to determine when a given selection is superseded
by a newer request uses < instead of <= to allow clients to make
multiple selection requests with the same serial number and have the
last one hold.
To limit memory use, a ring buffer is used to store runs of sequential
serial numbers, and all serial numbers earlier than the start of the
ring buffer are assumed to be valid. Faking very old serials is
unlikely to be disruptive.
Assuming all clients are correctly written, the only additional
constraint which this patch should impose is that serial numbers
are now bound to seats: clients may not receive a serial number
from an input event on one seat and then use that to request
copy-selection on another seat.
This makes compositors able to block and/or customize set_selection requests
coming from clients. For instance, it's possible for a compositor to disable
rich selection content (by removing all MIME types except text/plain). This
commit implements the design proposed in [1].
Two new events are added to wlr_seat: request_set_selection and
request_set_primary_selection. Compositors need to listen to these events and
either destroy the source or effectively set the selection.
Fixes https://github.com/swaywm/wlroots/issues/1138
[1]: https://github.com/swaywm/wlroots/issues/1367#issuecomment-442403454
This is a common interface that can be used for all primary selection
protocols, as discussed in [1]. A new function wlr_seat_set_primary_selection
is added to set the primary selection for all protocols.
The seat now owns again the source, and resets the selection to NULL when
destroyed.
[1]: https://github.com/swaywm/wlroots/issues/1367#issuecomment-442403454
When a client was creating multiple data devices for the same seat, we were
only creating one resource. This is a protocol error.
Instead, create one offer per data device.
This commit also makes offers inert when their source is destroyed.
Fixes part of https://github.com/swaywm/wlroots/issues/1041
Supersedes https://github.com/swaywm/wlroots/pull/1113
seat->primary_election_source_destroy points to the source that just got
freed by the cancel.
==7843==ERROR: AddressSanitizer: heap-use-after-free on address 0x60b0004269b0 at pc 0x7fb95bf4ccd0 bp 0x7ffd75013940 s
p 0x7ffd75013930
WRITE of size 8 at 0x60b0004269b0 thread T0
#0 0x7fb95bf4cccf in wl_list_remove ../util/signal.c:55
#1 0x7fb95bf3f4c6 in wlr_seat_set_primary_selection ../types/wlr_primary_selection.c:238
#2 0x7fb95becb1a7 in xwm_handle_selection_event ../xwayland/selection/selection.c:124
#3 0x7fb95bed2e5d in x11_event_handler ../xwayland/xwm.c:1139
#4 0x7fb95c1bdf01 in wl_event_loop_dispatch src/event-loop.c:641
#5 0x7fb95c1bc601 in wl_display_run src/wayland-server.c:1260
#6 0x40a2f4 in main ../sway/main.c:433
#7 0x7fb95b69718a in __libc_start_main (/lib64/libc.so.6+0x2318a)
#8 0x40b749 in _start (/opt/wayland/bin/sway+0x40b749)
0x60b0004269b0 is located 64 bytes inside of 112-byte region [0x60b000426970,0x60b0004269e0)
freed by thread T0 here:
#0 0x7fb95e0ad880 in __interceptor_free (/lib64/libasan.so.5+0xee880)
#1 0x7fb95bf3f49e in wlr_seat_set_primary_selection ../types/wlr_primary_selection.c:236
#2 0x7fb95becb1a7 in xwm_handle_selection_event ../xwayland/selection/selection.c:124
#3 0x7fb95bed2e5d in x11_event_handler ../xwayland/xwm.c:1139
#4 0x7fb95c1bdf01 in wl_event_loop_dispatch src/event-loop.c:641
previously allocated by thread T0 here:
#0 0x7fb95e0ade50 in calloc (/lib64/libasan.so.5+0xeee50)
#1 0x7fb95bec7ad6 in xwm_selection_get_targets ../xwayland/selection/incoming.c:355
#2 0x7fb95bec7ad6 in xwm_handle_selection_notify ../xwayland/selection/incoming.c:402
#3 0x7fb95becb1a7 in xwm_handle_selection_event ../xwayland/selection/selection.c:124
#4 0x7fb95bed2e5d in x11_event_handler ../xwayland/xwm.c:1139
#5 0x7fb95c1bdf01 in wl_event_loop_dispatch src/event-loop.c:641
SUMMARY: AddressSanitizer: heap-use-after-free ../util/signal.c:55 in wl_list_remove
Shadow bytes around the buggy address:
0x0c168007cce0: fd fd fd fa fa fa fa fa fa fa fa fa fd fd fd fd
0x0c168007ccf0: fd fd fd fd fd fd fd fd fd fa fa fa fa fa fa fa
0x0c168007cd00: fa fa fd fd fd fd fd fd fd fd fd fd fd fd fd fa
0x0c168007cd10: fa fa fa fa fa fa fa fa fd fd fd fd fd fd fd fd
0x0c168007cd20: fd fd fd fd fd fa fa fa fa fa fa fa fa fa fd fd
=>0x0c168007cd30: fd fd fd fd fd fd[fd]fd fd fd fd fd fa fa fa fa
0x0c168007cd40: fa fa fa fa fd fd fd fd fd fd fd fd fd fd fd fd
0x0c168007cd50: fd fa fa fa fa fa fa fa fa fa fd fd fd fd fd fd
0x0c168007cd60: fd fd fd fd fd fd fd fa fa fa fa fa fa fa fa fa
0x0c168007cd70: fd fd fd fd fd fd fd fd fd fd fd fd fd fa fa fa
0x0c168007cd80: fa fa fa fa fa fa fd fd fd fd fd fd fd fd fd fd
Manuel Stoeckl
emersion
Alexander Bakker
Dominique Martinet
Drew DeVault
Scott Anderson