gcc-8 complains:
tapdisk-vbd.c: In function 'tapdisk_vbd_resume_ring':
tapdisk-vbd.c:1671:53: error: 'snprintf' output may be truncated before the last format character [-Werror=format-truncation=]
snprintf(params.name, sizeof(params.name) - 1, "%s", message);
^
tapdisk-vbd.c:1671:3: note: 'snprintf' output between 1 and 256 bytes into a destination of size 255
snprintf(params.name, sizeof(params.name) - 1, "%s", message);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The "- 1" in buffer size should be actually applied to message, to leave
place for terminating '\0', not the other way around (truncate '\0' even
if it would fit).
In function 'tapdisk_control_open_image',
inlined from 'tapdisk_control_handle_request' at tapdisk-control.c:660:10:
tapdisk-control.c:465:2: error: 'strncpy' specified bound 256 equals destination size [-Werror=stringop-truncation]
strncpy(params.name, vbd->name, BLKTAP2_MAX_MESSAGE_LEN);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In function 'tapdisk_control_create_socket',
inlined from 'tapdisk_control_open' at tapdisk-control.c:836:9:
tapdisk-control.c:793:2: error: 'strncpy' specified bound 108 equals destination size [-Werror=stringop-truncation]
strncpy(saddr.sun_path, td_control.path, sizeof(saddr.sun_path));
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
block-qcow.c: In function 'qcow_create':
block-qcow.c:1216:5: error: 'strncpy' specified bound 4096 equals destination size [-Werror=stringop-truncation]
strncpy(backing_filename, backing_file,
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
sizeof(backing_filename));
~~~~~~~~~~~~~~~~~~~~~~~~~
I those cases, reduce size of copied string and make sure final '\0' is
added.
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Release-Acked-by: Juergen Gross <jgross@suse.com>
Tapdisk control in userspace, a replacement for the original blktap2
control stack, which had to pass a kernel space interface based on
sysfs nodes.
All tapdisk processes listen for commands on a unix stream socket. The
control library supports scanning the socket namespace for running
tapdisks, VBD minors allocated, associated images and state inquiry.
Control operations include allocating/releasing devices, spawning
tapdisks, opening/closing images, attaching disk images to
devices. disk pause/resume operations and runtime switching of disk
images.
Signed-off-by: Jake Wires <jake.wires@citrix.com>
Signed-off-by: Daniel Stodden <daniel.stodden@citrix.com>
Marek Marczykowski-Górecki
Wei Liu
Jan Beulich
Keir Fraser