[PATCH v3 02/11] platform/x86/intel/pmt: crashlog binary file endpoint

[Michael J. Ruhl]

Usage of the intel_pmt_read() for binary sysfs, requires an allocated
endpoint struct. The crashlog driver does not allocate the endpoint.

Without the ep, the crashlog usage causes the following NULL pointer
exception:

BUG: kernel NULL pointer dereference, address: 0000000000000000
Oops: Oops: 0000 [#1] SMP NOPTI
RIP: 0010:intel_pmt_read+0x3b/0x70 [pmt_class]
Code:
Call Trace:
 <TASK>
 ? sysfs_kf_bin_read+0xc0/0xe0
 kernfs_fop_read_iter+0xac/0x1a0
 vfs_read+0x26d/0x350
 ksys_read+0x6b/0xe0
 __x64_sys_read+0x1d/0x30
 x64_sys_call+0x1bc8/0x1d70
 do_syscall_64+0x6d/0x110

Add the endpoint information to the crashlog driver to avoid the NULL
pointer exception.

Fixes: 416eeb2e1fc7 ("platform/x86/intel/pmt: telemetry: Export API to read telemetry")
Cc: <stable at vger.kernel.org>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl at intel.com>
---
 drivers/platform/x86/intel/pmt/crashlog.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/platform/x86/intel/pmt/crashlog.c b/drivers/platform/x86/intel/pmt/crashlog.c
index 6a9eb3c4b313..74ce199e59f0 100644
--- a/drivers/platform/x86/intel/pmt/crashlog.c
+++ b/drivers/platform/x86/intel/pmt/crashlog.c
@@ -252,6 +252,7 @@ static struct intel_pmt_namespace pmt_crashlog_ns = {
 	.xa = &crashlog_array,
 	.attr_grp = &pmt_crashlog_group,
 	.pmt_header_decode = pmt_crashlog_header_decode,
+	.pmt_add_endpoint = intel_pmt_add_endpoint,
 };
 
 /*
@@ -262,8 +263,12 @@ static void pmt_crashlog_remove(struct auxiliary_device *auxdev)
 	struct pmt_crashlog_priv *priv = auxiliary_get_drvdata(auxdev);
 	int i;
 
-	for (i = 0; i < priv->num_entries; i++)
-		intel_pmt_dev_destroy(&priv->entry[i].entry, &pmt_crashlog_ns);
+	for (i = 0; i < priv->num_entries; i++) {
+		struct intel_pmt_entry *entry = &priv->entry[i].entry;
+
+		intel_pmt_release_endpoint(entry->ep);
+		intel_pmt_dev_destroy(entry, &pmt_crashlog_ns);
+	}
 }
 
 static int pmt_crashlog_probe(struct auxiliary_device *auxdev,
-- 
2.49.0