In src/afl-fuzz.c `prev_queued_items` is used to decide whether the alias table should be recreated through the comparison with `afl->queued_items`.
43f462c91b/src/afl-fuzz.c (L3103-L3117)
However, this variable is also updated to `afl->queued_items` when INTROSPECTION is enabled and the `fuzz_one` appends seeds.
43f462c91b/src/afl-fuzz.c (L3135-L3140)
Due to the update of `prev_queued_items` when INTROSPECTION is on, alias table may not be recreated when it actually should be.
This can lead to potential heap buffer-overflow in `select_next_queue_entry` due to the lack of `afl_realloc` called in `create_alias_table`.
This patch fixes this bug by utilizing another variable for the INTROSPECTION part like other variables such as `prev_saved_tmouts`.
Using `__attribute__((fallthrough))` makes fallthroughs explicit in a way the compiler can understand. This allows the enablement of `-Wimplicit-fallthrough`.
Use the __builtin_popcount intrinsic to optimize the bit counting
function if the compiler supports it. This change replaces the manual
bit counting algorithm with the more efficient built-in function, which
leverages hardware support on compatible processors.
This modification ensures that the code remains backward-compatible by
falling back to the original implementation when __builtin_popcount is
not available.
With CODE_COVERAGE builds, we need to collect the coverage data of each
iteration in a persistant buffer that has the same size as the regular
trace buffer used for fuzzing. We dump this information at the end of
the run and when combined with pointer data and module info, this can be
used to calculate code coverage.
According to the C standard, left-shifting a value by an amount greater
than or equal to the width of its promoted type results in undefined
behavior. To prevent potential unexpected results, explicitly cast the
uint8_t variable type to uint64_t before performing the left shift
operation by 56 bits. This ensures the operation is well-defined and
adheres to the standard.
Fixes: 40df85d1 ("adjust cmplog header")
