GCC 8 introduced the -Wstringop-overflow, which detect buffer overflow
by string-modifying functions declared in <string.h>, such strncpy(),
used in global_state_store_running().
GCC indeed found an incorrect use of strlen(), because this array
is loaded by VMSTATE_BUFFER(runstate, GlobalState) then parsed
using qapi_enum_parse which does not get the buffer length.
Use strnlen() which returns sizeof(s->runstate) if the array is not
NUL-terminated, assert the size is within range, and enforce the array
to be NUL-terminated to avoid an overflow in qapi_enum_parse().
This fixes:
CC migration/global_state.o
qemu/migration/global_state.c: In function 'global_state_pre_save':
qemu/migration/global_state.c:109:15: error: 'strlen' argument 1 declared attribute 'nonstring' [-Werror=stringop-overflow=]
s->size = strlen((char *)s->runstate) + 1;
^~~~~~~~~~~~~~~~~~~~~~~~~~~
qemu/migration/global_state.c:24:13: note: argument 'runstate' declared here
uint8_t runstate[100] QEMU_NONSTRING;
^~~~~~~~
cc1: all warnings being treated as errors
make: *** [qemu/rules.mak:69: migration/global_state.o] Error 1
Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
GCC 8 added a -Wstringop-truncation warning:
The -Wstringop-truncation warning added in GCC 8.0 via r254630 for
bug 81117 is specifically intended to highlight likely unintended
uses of the strncpy function that truncate the terminating NUL
character from the source string.
This new warning leads to compilation failures:
CC migration/global_state.o
qemu/migration/global_state.c: In function 'global_state_store_running':
qemu/migration/global_state.c:45:5: error: 'strncpy' specified bound 100 equals destination size [-Werror=stringop-truncation]
strncpy((char *)global_state.runstate, state, sizeof(global_state.runstate));
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
make: *** [qemu/rules.mak:69: migration/global_state.o] Error 1
Adding an assert is enough to silence GCC.
(alternatively, we could hard-code "running")
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
[PMD: More verbose commit message]
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Modify the pre_save method on VMStateDescription to return an int
rather than void so that it potentially can fail.
Changed zillions of devices to make them return 0; the only
case I've made it return non-0 is hw/intc/s390_flic_kvm.c that already
had an error_report/return case.
Note: If you add an error exit in your pre_save you must emit
an error_report to say why.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20170925112917.21340-2-dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Currently, a FOO_lookup is an array of strings terminated by a NULL
sentinel.
A future patch will generate enums with "holes". NULL-termination
will cease to work then.
To prepare for that, store the length in the FOO_lookup by wrapping it
in a struct and adding a member for the length.
The sentinel will be dropped next.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20170822132255.23945-13-marcandre.lureau@redhat.com>
[Basically redone]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1503564371-26090-16-git-send-email-armbru@redhat.com>
[Rebased]
The next commit will put it to use. May look pointless now, but we're
going to change the FOO_lookup's type, and then it'll help.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1503564371-26090-13-git-send-email-armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
The lookup tables have a sentinel, no need to make callers pass their
size.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1503564371-26090-3-git-send-email-armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[Rebased, commit message corrected]
Put it into MigrationState then we can use the properties to specify
whether to enable storing global state.
Removing global_state_set_optional() since now we can use HW_COMPAT_2_3
for x86/power, and AccelClass.global_props for Xen.
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1498536619-14548-6-git-send-email-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
It don't belong anywhere else, just the global state where everybody
can stick other things.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Philippe Mathieu-Daudé
Marc-André Lureau
Dr. David Alan Gilbert
Markus Armbruster
Peter Xu
Juan Quintela