Make sure that extra UNPOISON calls do not cause the poisoning counter
to underflow and wrap around.
Memory that is unpoisoned multiple times should remain unpoisoned.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
This allows unusually-nested memory poisoning to work correctly, since
it keeps track of whether any buffers are still poisoned, rather than
just disabling poisoning at the first call to the UNPOISON() macro.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
Allow memory poisoning to be enabled and disabled at runtime using a
thread-local flag. This allows poisoning to be disabled whenever a PSA
function is called but not through the test wrappers, removing false
positive use-after-poisons.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
Asan poisons memory with an 8-byte granularity. We want to make sure that
the whole specified region is poisoned (our typical use case is a
heap-allocated object, and we want to poison the whole object, and we don't
care about the bytes after the end of the object and up to the beginning of
the next object). So align the start and end of the region to (un)poison to
an 8-byte boundary.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
While an area of memory is poisoned, reading or writing from it triggers a
sanitizer violation.
Implemented for ASan.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
