Dan Williams dan.j.williams@intel.com writes:
On Tue, Jan 15, 2019 at 6:16 AM Jeff Moyer jmoyer@redhat.com wrote:
Dan Williams dan.j.williams@intel.com writes:
Changes since v1 [1]:
- Include another patch make sure that function-number zero can be safely used as an invalid function number (Jeff)
- Add a comment clarifying why zero is an invalid function number (Jeff)
- Pass nfit_mem to cmd_to_func() (Jeff)
- Collect a Tested-by from Sujith
For the series:
Reviewed-by: Jeff Moyer jmoyer@redhat.com
Thanks, Dan!
Thanks, although I just realized one more change. The ND_CMD_CALL case should zero out command after the function translation, otherwise userspace can call functions that the kernel is blocking in the dsm_mask.
Holler if this invalidates your "Reviewed-by".
AAAAAAAHHHHHHHHHH!!!!
:)
diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c index 87e02f281e51..d7747aceb7ab 100644 --- a/drivers/acpi/nfit/core.c +++ b/drivers/acpi/nfit/core.c @@ -463,6 +463,12 @@ int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc, struct nvdimm *nvdimm, func = cmd_to_func(nfit_mem, cmd, buf); if (func < 0) return func;
/** In the ND_CMD_CALL case we're now dependent on 'func'* being validated by the dimm's dsm_mask*/if (cmd == ND_CMD_CALL)cmd = 0; dimm_name = nvdimm_name(nvdimm); cmd_name = nvdimm_cmd_name(cmd); cmd_mask = nvdimm_cmd_mask(nvdimm);
dsm_mask = nfit_mem->dsm_mask; desc = nd_cmd_dimm_desc(cmd);
That sure doesn't look right. Now cmd_name and desc will be wrong.
@@ -477,8 +483,10 @@ int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc, struct nvdimm *nvdimm, cmd_name = nvdimm_bus_cmd_name(cmd); cmd_mask = nd_desc->cmd_mask; dsm_mask = cmd_mask;
if (cmd == ND_CMD_CALL)
if (cmd == ND_CMD_CALL) { dsm_mask = nd_desc->bus_dsm_mask;cmd = 0;} desc = nd_cmd_bus_desc(cmd);
And again here.
We could reorder the zeroing, or you could modify the check for a valid comand/function. Something like this?
/* * 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)) return -ENOTTY; else if (!test_bit(cmd, &cmd_mask)) return -ENOTTY;
Which way do you think is cleaner?
Cheers, Jeff