linux/mm/kmsan
Alexander Potapenko bd6f3421a5 mm: kmsan: handle alloc failures in kmsan_vmap_pages_range_noflush()
commit 47ebd0310e upstream.

As reported by Dipanjan Das, when KMSAN is used together with kernel fault
injection (or, generally, even without the latter), calls to kcalloc() or
__vmap_pages_range_noflush() may fail, leaving the metadata mappings for
the virtual mapping in an inconsistent state.  When these metadata
mappings are accessed later, the kernel crashes.

To address the problem, we return a non-zero error code from
kmsan_vmap_pages_range_noflush() in the case of any allocation/mapping
failure inside it, and make vmap_pages_range_noflush() return an error if
KMSAN fails to allocate the metadata.

This patch also removes KMSAN_WARN_ON() from vmap_pages_range_noflush(),
as these allocation failures are not fatal anymore.

Link: https://lkml.kernel.org/r/20230413131223.4135168-1-glider@google.com
Fixes: b073d7f8ae ("mm: kmsan: maintain KMSAN metadata for page operations")
Signed-off-by: Alexander Potapenko <glider@google.com>
Reported-by: Dipanjan Das <mail.dipanjan.das@gmail.com>
  Link: https://lore.kernel.org/linux-mm/CANX2M5ZRrRA64k0hOif02TjmY9kbbO2aCBPyq79es34RXZ=cAw@mail.gmail.com/
Reviewed-by: Marco Elver <elver@google.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-26 14:28:41 +02:00
..
core.c kmsan: handle task creation and exiting 2022-10-03 14:03:20 -07:00
hooks.c mm: kmsan: handle alloc failures in kmsan_ioremap_page_range() 2023-04-26 14:28:41 +02:00
init.c init: kmsan: call KMSAN initialization routines 2022-10-03 14:03:21 -07:00
instrumentation.c x86: fortify: kmsan: fix KMSAN fortify builds 2022-10-28 13:37:23 -07:00
kmsan_test.c kmsan: include linux/vmalloc.h 2023-01-04 11:28:59 +01:00
kmsan.h kmsan: core: kmsan_in_runtime() should return true in NMI context 2022-11-08 15:57:24 -08:00
Makefile kmsan: add tests for KMSAN 2022-10-03 14:03:22 -07:00
report.c
shadow.c mm: kmsan: handle alloc failures in kmsan_vmap_pages_range_noflush() 2023-04-26 14:28:41 +02:00