[PATCH 1/2] acpi/nfit: improve bounds checking for 'func'

[PATCH 1/2] acpi/nfit: improve bounds checking for 'func'

[Dan Carpenter]

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@oracle.com>
---
 drivers/acpi/nfit/core.c | 10 ++++++----
 drivers/acpi/nfit/nfit.h |  1 +
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/acpi/nfit/nfit.h b/drivers/acpi/nfit/nfit.h
index 24241941181c..b317f4043705 100644
--- 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 \
diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
index a3320f93616d..d0090f71585c 100644
--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -360,7 +360,7 @@ static union acpi_object *acpi_label_info(acpi_handle handle)
 
 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, unsigned func)
 
 	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_descriptor *nd_desc, struct nvdimm *nvdimm,
 	 * 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;
@@ -3492,7 +3493,8 @@ static int acpi_nfit_clear_to_send(struct nvdimm_bus_descriptor *nd_desc,
 	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;
 	}
 
-- 
2.11.0
_______________________________________________
Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org
To unsubscribe send an email to linux-nvdimm-leave@lists.01.org

[PATCH 2/2] libnvdimm: Out of bounds read in __nd_ioctl()

[Dan Carpenter]

The "cmd" comes from the user and it can be up to 255.  It it's more
than the number of bits in long, it results out of bounds read when we
check test_bit(cmd, &cmd_mask).  The highest valid value for "cmd" is
ND_CMD_CALL (10) so I added a compare against that.

Fixes: 62232e45f4a2 ("libnvdimm: control (ioctl) messages for nvdimm_bus and nvdimm devices")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
 drivers/nvdimm/bus.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c
index a8b515968569..09087c38fabd 100644
--- a/drivers/nvdimm/bus.c
+++ b/drivers/nvdimm/bus.c
@@ -1042,8 +1042,10 @@ static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm,
 			return -EFAULT;
 	}
 
-	if (!desc || (desc->out_num + desc->in_num == 0) ||
-			!test_bit(cmd, &cmd_mask))
+	if (!desc ||
+	    (desc->out_num + desc->in_num == 0) ||
+	    cmd > ND_CMD_CALL ||
+	    !test_bit(cmd, &cmd_mask))
 		return -ENOTTY;
 
 	/* fail write commands (when read-only) */
-- 
2.11.0
_______________________________________________
Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org
To unsubscribe send an email to linux-nvdimm-leave@lists.01.org

Re: [PATCH 1/2] acpi/nfit: improve bounds checking for 'func'

[Dan Williams]

On Tue, Feb 25, 2020 at 8:20 AM Dan Carpenter <dan.carpenter@oracle.com> wrote:
>
> 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@oracle.com>

Reviewed-by: Dan Williams <dan.j.williams@intel.com>

I'll apply this to my fixes branch.
_______________________________________________
Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org
To unsubscribe send an email to linux-nvdimm-leave@lists.01.org

Re: [PATCH 2/2] libnvdimm: Out of bounds read in __nd_ioctl()

[Dan Williams]

On Tue, Feb 25, 2020 at 8:21 AM Dan Carpenter <dan.carpenter@oracle.com> wrote:
>
> The "cmd" comes from the user and it can be up to 255.  It it's more
> than the number of bits in long, it results out of bounds read when we
> check test_bit(cmd, &cmd_mask).  The highest valid value for "cmd" is
> ND_CMD_CALL (10) so I added a compare against that.
>
> Fixes: 62232e45f4a2 ("libnvdimm: control (ioctl) messages for nvdimm_bus and nvdimm devices")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

Looks good, applied.
_______________________________________________
Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org
To unsubscribe send an email to linux-nvdimm-leave@lists.01.org