qemu/scripts/coverity-scan
Vladimir Sementsov-Ogievskiy adff55b520 coverity: physmem: use simple assertions instead of modelling
Unfortunately Coverity doesn't follow the logic aroung "len" and "l"
variables in stacks finishing with flatview_{read,write}_continue() and
generate a lot of OVERRUN false-positives. When small buffer (2 or 4
bytes) is passed to mem read/write path, Coverity assumes the worst
case of sz=8 in stn_he_p()/ldn_he_p() (defined in
include/qemu/bswap.h), and reports buffer overrun.

To silence these false-positives we have model functions, which hide
real logic from Coverity.

However, it turned out that these new two assertions are enough to
quiet Coverity.

Assertions are better than hiding the logic, so let's drop the
modelling and move to assertions for memory r/w call stacks.

After patch, the sequence

 cov-make-library --output-file /tmp/master.xmldb \
    scripts/coverity-scan/model.c
 cov-build --dir ~/covtmp/master make -j9
 cov-analyze --user-model-file /tmp/master.xmldb \
    --dir ~/covtmp/master --all --strip-path "$(pwd)
 cov-format-errors --dir ~/covtmp/master \
    --html-output ~/covtmp/master_html_report

Generate for me the same big set of CIDs excepept for 6 disappeared (so
it becomes even better).

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Acked-by: David Hildenbrand <david@redhat.com>
Message-ID: <20231005140326.332830-1-vsementsov@yandex-team.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-24 12:07:47 +01:00
..
COMPONENTS.md system: Rename softmmu/ directory as system/ 2023-10-08 21:08:08 +02:00
coverity-scan.docker coverity: unify Fedora dockerfiles 2023-04-20 11:17:36 +02:00
model.c coverity: physmem: use simple assertions instead of modelling 2023-11-24 12:07:47 +01:00
run-coverity-scan Replacing CONFIG_VNC_PNG with CONFIG_PNG 2022-04-27 07:50:28 +02:00