Six findings, all of them libakgl's, all closed. The memcheck run is clean.
Not one of the four json_load_file calls in src/ was ever matched by a
json_decref, so every asset load abandoned its parsed document: 1.5 KB per
sprite, 2.1 KB per character, 9 KB per load of the 2x2 fixture map, and on
the order of a megabyte for a real one. Each loader now releases it in the
CLEANUP block it already had, on the success path as well as the failure
one. akgl_registry_load_properties needed its loop moved inside the ATTEMPT
block first: props is a borrowed reference into the document and is read
after the block ends, so every exit from that loop leaked the whole tree.
akgl_get_property copied a fixed AKGL_MAX_STRING_LENGTH bytes out of what
SDL handed back, which is SDL's strdup of the value -- four bytes for
"0.0". That read up to 4 KiB past the end of somebody else's allocation on
every property read, returned whatever was there past the terminator, and
would have faulted on a value that landed at the end of a page. It copies
the value and its terminator now, and refuses a value too long for an
akgl_String rather than truncating it into an unterminated buffer. The
header note that described the overread as a quirk describes correct
behaviour instead.
The four savegame name tables wrote a fixed-width field starting at the
registry key, and SDL sizes that allocation to the name. They read past it
on every entry and put what they found into the save file: up to half a
kilobyte of this process's heap per registered object, in a file a player
might send to somebody. They stage through a zeroed buffer now, and a
negative-array-size typedef fails the build if a table's width ever outgrows
it.
akgl_controller_list_keyboards never freed the array SDL_GetKeyboards
allocated for it.
A font could be opened and published and never handed back -- there was no
way to close one, so a game that changed fonts between scenes leaked ten
kilobytes each time, and loading over a live name leaked the font it
displaced. akgl_text_unloadfont is that missing half, and akgl_text_loadfont
calls it when it replaces a name, after the new font has opened so a failed
reload leaves the caller with the font they had. A new public symbol takes
the version to 0.4.0 and the soname with it: an 0.3 consumer cannot be
handed this library and told it is the same ABI.
tests/registry.c fills a destination with a sentinel and asserts the bytes
past the terminator survive a read, which fails against the old copy.
tests/text.c covers unload, double unload, unloading a name that was never
registered, and replacement closing the displaced font. The JSON releases
have no test of their own and cannot sensibly have one -- nothing in the
public API can observe a jansson refcount -- so the memcheck run is their
test, which is an argument for gating it rather than against.
The two remaining findings are in deps/semver's own unit test, which is
vendored. They are suppressed by function name, so a rewrite of those cases
comes back as a finding.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
`cmake --build build --target memcheck` runs every registered CTest suite
under valgrind. There are no new test programs, and there should not be any:
tests/benchutil.h notices valgrind in LD_PRELOAD and drops the benchmark
scale to 0.0005, which turns the perf suites into the broadest path coverage
in the tree at a cost valgrind can survive. A benchmark walks one path a
hundred thousand times; a leak check wants every path walked once. Same
binaries, one flag apart, and the whole run is about thirty seconds.
scripts/memcheck.sh wraps `ctest -T memcheck` because that command records
defects and still exits 0, which cannot gate anything. It also forces the
headless drivers, so the vendor GPU stack is never loaded -- that removes
thousands of unfixable findings inside amdgpu_dri.so without suppressing
anything, and it is what the suites are written for anyway. Only definite
losses, invalid accesses and uninitialised reads count; "still reachable" is
what SDL and FreeType keep for the process lifetime and says nothing about
this library. The three suppressions in scripts/valgrind.supp are each a
decision that a finding belongs to somebody else.
Six defects, all filed in TODO.md under "Memory checking", the first of
which is the one that matters: not one of the four json_load_file calls in
src/ is ever matched by a json_decref, so every asset load abandons its
parsed document -- 1.5 KB per sprite, 2.1 KB per character, 9 KB per load of
the 2x2 fixture map, and on the order of a megabyte for a real one. A game
that reloads a level on death leaks a level's worth of JSON every time.
akgl_get_property also reads up to 4 KiB past the end of every property
value it copies, and the savegame name tables read past the end of every
registry key and write what they find into the file.
tests/util.c zeroes three fixtures it used to leave as stack garbage. The
library was never at fault there -- the tests handed it uninitialised floats
and then made one real call with them -- but sixteen findings of noise in a
new gate is how a gate gets ignored.
The unit suites' TIMEOUT goes from 30 to 300 because CTest applies the same
property to the checked run, where everything is twenty times slower.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
