libnvdimm, tools/testing/nvdimm: fix 'ars_status' output buffer sizing

Use the output length specified in the command to size the receive
buffer rather than the arbitrary 4K limit.

This bug was hiding the fact that the ndctl implementation of
ndctl_bus_cmd_new_ars_status() was not specifying an output buffer size.

Cc: <stable@vger.kernel.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/drivers/acpi/nfit.c b/drivers/acpi/nfit.c
index 424b362e8fdc447ca2e3fdae45457e3bb7f1dde0..1d4b9c6bdf45deae058f1749d6c245ad83ea5b48 100644 (file)
--- a/drivers/acpi/nfit.c
+++ b/drivers/acpi/nfit.c
@@ -1516,13 +1516,13 @@ static int ars_do_start(struct nvdimm_bus_descriptor *nd_desc,
 }
 
 static int ars_get_status(struct nvdimm_bus_descriptor *nd_desc,
-               struct nd_cmd_ars_status *cmd)
+               struct nd_cmd_ars_status *cmd, u32 size)
 {
        int rc;
 
        while (1) {
                rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_STATUS, cmd,
-                       sizeof(*cmd));
+                       size);
                if (rc || cmd->status & 0xffff)
                        return -ENXIO;
 
@@ -1580,6 +1580,7 @@ static int acpi_nfit_find_poison(struct acpi_nfit_desc *acpi_desc,
        struct nd_cmd_ars_start *ars_start = NULL;
        struct nd_cmd_ars_cap *ars_cap = NULL;
        u64 start, len, cur, remaining;
+       u32 ars_status_size;
        int rc;
 
        ars_cap = kzalloc(sizeof(*ars_cap), GFP_KERNEL);
@@ -1609,14 +1610,14 @@ static int acpi_nfit_find_poison(struct acpi_nfit_desc *acpi_desc,
         * Check if a full-range ARS has been run. If so, use those results
         * without having to start a new ARS.
         */
-       ars_status = kzalloc(ars_cap->max_ars_out + sizeof(*ars_status),
-                       GFP_KERNEL);
+       ars_status_size = ars_cap->max_ars_out;
+       ars_status = kzalloc(ars_status_size, GFP_KERNEL);
        if (!ars_status) {
                rc = -ENOMEM;
                goto out;
        }
 
-       rc = ars_get_status(nd_desc, ars_status);
+       rc = ars_get_status(nd_desc, ars_status, ars_status_size);
        if (rc)
                goto out;
 
@@ -1646,7 +1647,7 @@ static int acpi_nfit_find_poison(struct acpi_nfit_desc *acpi_desc,
                if (rc)
                        goto out;
 
-               rc = ars_get_status(nd_desc, ars_status);
+               rc = ars_get_status(nd_desc, ars_status, ars_status_size);
                if (rc)
                        goto out;
 

diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c
index 7e2c43f701bc451463c5273ed3a5a1e49f6be15f..99953b34fa1db6f6130fa0191d1328efd3311efa 100644 (file)
--- a/drivers/nvdimm/bus.c
+++ b/drivers/nvdimm/bus.c
@@ -392,8 +392,8 @@ static const struct nd_cmd_desc __nd_cmd_bus_descs[] = {
                .out_sizes = { 4, },
        },
        [ND_CMD_ARS_STATUS] = {
-               .out_num = 2,
-               .out_sizes = { 4, UINT_MAX, },
+               .out_num = 3,
+               .out_sizes = { 4, 4, UINT_MAX, },
        },
 };
 
@@ -442,8 +442,8 @@ u32 nd_cmd_out_size(struct nvdimm *nvdimm, int cmd,
                return in_field[1];
        else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2)
                return out_field[1];
-       else if (!nvdimm && cmd == ND_CMD_ARS_STATUS && idx == 1)
-               return ND_CMD_ARS_STATUS_MAX;
+       else if (!nvdimm && cmd == ND_CMD_ARS_STATUS && idx == 2)
+               return out_field[1] - 8;
 
        return UINT_MAX;
 }

diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h
index bed40dff0e86999b5c39c82ebadc29f25e0060ec..c736382fd2609baee8d792f03c25f65cdfa538d7 100644 (file)
--- a/include/linux/libnvdimm.h
+++ b/include/linux/libnvdimm.h
@@ -28,7 +28,6 @@ enum {
        ND_IOCTL_MAX_BUFLEN = SZ_4M,
        ND_CMD_MAX_ELEM = 4,
        ND_CMD_MAX_ENVELOPE = 16,
-       ND_CMD_ARS_STATUS_MAX = SZ_4K,
        ND_MAX_MAPPINGS = 32,
 
        /* region flag indicating to direct-map persistent memory by default */

diff --git a/tools/testing/nvdimm/test/nfit.c b/tools/testing/nvdimm/test/nfit.c
index 90bd2ea4103232b68e29e167873ff21a3f76b262..b3281dcd4a5d5502af9f66720dfcdccb1aca4d58 100644 (file)
--- a/tools/testing/nvdimm/test/nfit.c
+++ b/tools/testing/nvdimm/test/nfit.c
@@ -217,13 +217,16 @@ static int nfit_test_cmd_set_config_data(struct nd_cmd_set_config_hdr *nd_cmd,
        return rc;
 }
 
+#define NFIT_TEST_ARS_RECORDS 4
+
 static int nfit_test_cmd_ars_cap(struct nd_cmd_ars_cap *nd_cmd,
                unsigned int buf_len)
 {
        if (buf_len < sizeof(*nd_cmd))
                return -EINVAL;
 
-       nd_cmd->max_ars_out = 256;
+       nd_cmd->max_ars_out = sizeof(struct nd_cmd_ars_status)
+               + NFIT_TEST_ARS_RECORDS * sizeof(struct nd_ars_record);
        nd_cmd->status = (ND_ARS_PERSISTENT | ND_ARS_VOLATILE) << 16;
 
        return 0;
@@ -246,7 +249,8 @@ static int nfit_test_cmd_ars_status(struct nd_cmd_ars_status *nd_cmd,
        if (buf_len < sizeof(*nd_cmd))
                return -EINVAL;
 
-       nd_cmd->out_length = 256;
+       nd_cmd->out_length = sizeof(struct nd_cmd_ars_status);
+       /* TODO: emit error records */
        nd_cmd->num_records = 0;
        nd_cmd->address = 0;
        nd_cmd->length = -1ULL;