From: Dan Carpenter <dan.carpenter@xxxxxxxxxx> commit 01091c496f920e634ea84b689f480c39016752a8 upstream. The 'func' variable can come from the user in the __nd_ioctl(). If it's too high then the (1 << func) shift in acpi_nfit_clear_to_send() is undefined. In acpi_nfit_ctl() we pass 'func' to test_bit(func, &dsm_mask) which could result in an out of bounds access. To fix these issues, I introduced the NVDIMM_CMD_MAX (31) define and updated nfit_dsm_revid() to use that define as well instead of magic numbers. Fixes: 11189c1089da ("acpi/nfit: Fix command-supported detection") Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Reviewed-by: Dan Williams <dan.j.williams@xxxxxxxxx> Link: https://lore.kernel.org/r/20200225161927.hvftuq7kjn547fyj@kili.mountain Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/acpi/nfit/core.c | 10 ++++++---- drivers/acpi/nfit/nfit.h | 1 + 2 files changed, 7 insertions(+), 4 deletions(-) --- a/drivers/acpi/nfit/core.c +++ b/drivers/acpi/nfit/core.c @@ -360,7 +360,7 @@ static union acpi_object *acpi_label_inf static u8 nfit_dsm_revid(unsigned family, unsigned func) { - static const u8 revid_table[NVDIMM_FAMILY_MAX+1][32] = { + static const u8 revid_table[NVDIMM_FAMILY_MAX+1][NVDIMM_CMD_MAX+1] = { [NVDIMM_FAMILY_INTEL] = { [NVDIMM_INTEL_GET_MODES] = 2, [NVDIMM_INTEL_GET_FWINFO] = 2, @@ -386,7 +386,7 @@ static u8 nfit_dsm_revid(unsigned family if (family > NVDIMM_FAMILY_MAX) return 0; - if (func > 31) + if (func > NVDIMM_CMD_MAX) return 0; id = revid_table[family][func]; if (id == 0) @@ -492,7 +492,8 @@ int acpi_nfit_ctl(struct nvdimm_bus_desc * Check for a valid command. For ND_CMD_CALL, we also have to * make sure that the DSM function is supported. */ - if (cmd == ND_CMD_CALL && !test_bit(func, &dsm_mask)) + if (cmd == ND_CMD_CALL && + (func > NVDIMM_CMD_MAX || !test_bit(func, &dsm_mask))) return -ENOTTY; else if (!test_bit(cmd, &cmd_mask)) return -ENOTTY; @@ -3499,7 +3500,8 @@ static int acpi_nfit_clear_to_send(struc if (nvdimm && cmd == ND_CMD_CALL && call_pkg->nd_family == NVDIMM_FAMILY_INTEL) { func = call_pkg->nd_command; - if ((1 << func) & NVDIMM_INTEL_SECURITY_CMDMASK) + if (func > NVDIMM_CMD_MAX || + (1 << func) & NVDIMM_INTEL_SECURITY_CMDMASK) return -EOPNOTSUPP; } --- a/drivers/acpi/nfit/nfit.h +++ b/drivers/acpi/nfit/nfit.h @@ -34,6 +34,7 @@ | ACPI_NFIT_MEM_NOT_ARMED | ACPI_NFIT_MEM_MAP_FAILED) #define NVDIMM_FAMILY_MAX NVDIMM_FAMILY_HYPERV +#define NVDIMM_CMD_MAX 31 #define NVDIMM_STANDARD_CMDMASK \ (1 << ND_CMD_SMART | 1 << ND_CMD_SMART_THRESHOLD | 1 << ND_CMD_DIMM_FLAGS \