lkdtm: Add READ_AFTER_FREE test
In a similar manner to WRITE_AFTER_FREE, add a READ_AFTER_FREE
test to test free poisoning features. Sample output when
no sanitization is present:
# echo READ_AFTER_FREE > /sys/kernel/debug/provoke-crash/DIRECT
[ 17.542473] lkdtm: Performing direct entry READ_AFTER_FREE
[ 17.543866] lkdtm: Value in memory before free: 12345678
[ 17.545212] lkdtm: Attempting bad read from freed memory
[ 17.546542] lkdtm: Memory was not poisoned
with slub_debug=P:
# echo READ_AFTER_FREE > /sys/kernel/debug/provoke-crash/DIRECT
[ 22.415531] lkdtm: Performing direct entry READ_AFTER_FREE
[ 22.416366] lkdtm: Value in memory before free: 12345678
[ 22.417137] lkdtm: Attempting bad read from freed memory
[ 22.417897] lkdtm: Memory correctly poisoned, calling BUG
Signed-off-by: Laura Abbott <labbott@fedoraproject.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
1 file changed