From: Alexander Lobakin <alexandr.lobakin@xxxxxxxxx> commit b0b0b77ea611e3088e9523e60860f4f41b62b235 upstream. KASAN reports: [ 4.668325][ T0] BUG: KASAN: wild-memory-access in dmar_parse_one_rhsa (arch/x86/include/asm/bitops.h:214 arch/x86/include/asm/bitops.h:226 include/asm-generic/bitops/instrumented-non-atomic.h:142 include/linux/nodemask.h:415 drivers/iommu/intel/dmar.c:497) [ 4.676149][ T0] Read of size 8 at addr 1fffffff85115558 by task swapper/0/0 [ 4.683454][ T0] [ 4.685638][ T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.19.0-rc3-00004-g0e862838f290 #1 [ 4.694331][ T0] Hardware name: Supermicro SYS-5018D-FN4T/X10SDV-8C-TLN4F, BIOS 1.1 03/02/2016 [ 4.703196][ T0] Call Trace: [ 4.706334][ T0] <TASK> [ 4.709133][ T0] ? dmar_parse_one_rhsa (arch/x86/include/asm/bitops.h:214 arch/x86/include/asm/bitops.h:226 include/asm-generic/bitops/instrumented-non-atomic.h:142 include/linux/nodemask.h:415 drivers/iommu/intel/dmar.c:497) after converting the type of the first argument (@nr, bit number) of arch_test_bit() from `long` to `unsigned long`[0]. Under certain conditions (for example, when ACPI NUMA is disabled via command line), pxm_to_node() can return %NUMA_NO_NODE (-1). It is valid 'magic' number of NUMA node, but not valid bit number to use in bitops. node_online() eventually descends to test_bit() without checking for the input, assuming it's on caller side (which might be good for perf-critical tasks). There, -1 becomes %ULONG_MAX which leads to an insane array index when calculating bit position in memory. For now, add an explicit check for @node being not %NUMA_NO_NODE before calling test_bit(). The actual logics didn't change here at all. [0] https://github.com/norov/linux/commit/0e862838f290147ea9c16db852d8d494b552d38d Fixes: ee34b32d8c29 ("dmar: support for parsing Remapping Hardware Static Affinity structure") Cc: stable@xxxxxxxxxxxxxxx # 2.6.33+ Reported-by: kernel test robot <oliver.sang@xxxxxxxxx> Signed-off-by: Alexander Lobakin <alexandr.lobakin@xxxxxxxxx> Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> Reviewed-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> Signed-off-by: Yury Norov <yury.norov@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/iommu/dmar.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/iommu/dmar.c +++ b/drivers/iommu/dmar.c @@ -475,7 +475,7 @@ static int dmar_parse_one_rhsa(struct ac if (drhd->reg_base_addr == rhsa->base_address) { int node = acpi_map_pxm_to_node(rhsa->proximity_domain); - if (!node_online(node)) + if (node != NUMA_NO_NODE && !node_online(node)) node = NUMA_NO_NODE; drhd->iommu->node = node; return 0;
