Pedro Falcato 09aec5f9b2 mm: kmsan: panic on failure to allocate early boot metadata ... Given large enough allocations and a machine with low enough memory (i.e a default QEMU VM), it's entirely possible that kmsan_init_alloc_meta_for_range's shadow+origin allocation fails. Instead of eating a NULL deref kernel oops, check explicitly for memblock_alloc() failure and panic with a nice error message. Alexander Potapenko said: For posterity, it is generally quite important for the allocated shadow and origin to be contiguous, otherwise an unaligned memory write may result in memory corruption (the corresponding unaligned shadow write will be assuming that shadow pages are adjacent). So instead of panicking we could have split the range into smaller ones until the allocation succeeds, but that would've led to hard-to-debug problems in the future. Link: https://lkml.kernel.org/r/20231016153446.132763-1-pedro.falcato@gmail.com Signed-off-by: Pedro Falcato <pedro.falcato@gmail.com> Reviewed-by: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Marco Elver <elver@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>		2023-10-25 16:47:10 -07:00
..
core.c	kmsan: simplify kmsan_internal_memmove_metadata()	2023-10-04 10:32:22 -07:00
hooks.c	mm: kmsan: use helper macro offset_in_page()	2023-08-21 13:37:29 -07:00
init.c
instrumentation.c
kmsan.h
kmsan_test.c	kmsan: introduce test_memcpy_initialized_gap()	2023-10-04 10:32:22 -07:00
Makefile
report.c
shadow.c	mm: kmsan: panic on failure to allocate early boot metadata	2023-10-25 16:47:10 -07:00