diff --git a/Documentation/ABI/testing/sysfs-devices-spdm b/Documentation/ABI/testing/sysfs-devices-spdm
index 2d6e5d513231..ed61405770d6 100644
--- a/Documentation/ABI/testing/sysfs-devices-spdm
+++ b/Documentation/ABI/testing/sysfs-devices-spdm
@@ -29,3 +29,52 @@ Description:
 		The reason why authentication support could not be determined
 		is apparent from "dmesg".  To re-probe authentication support
 		of PCI devices, exercise the "remove" and "rescan" attributes.
+
+
+What:		/sys/devices/.../certificates/
+What:		/sys/devices/.../certificates/slot[0-7]
+Date:		June 2024
+Contact:	Lukas Wunner <lukas@wunner.de>
+Description:
+		The "certificates" directory provides access to the certificate
+		chains contained in the up to 8 slots of a device.
+
+		A certificate chain is the concatenation of one or more ASN.1
+		DER-encoded X.509 v3 certificates (SPDM 1.0.0 sec 4.9.2.1).
+		It can be examined as follows::
+
+		 # openssl storeutl -text certificates/slot0
+
+		A common use case is to add the first certificate in a chain
+		to the keyring of trusted root certificates (".cma" in this
+		example) after comparing its fingerprint to the one provided
+		by the device manufacturer::
+
+		 # openssl x509 -in certificates/slot0 -fingerprint -nocert
+		 # openssl x509 -in certificates/slot0 -outform DER | \
+		   keyctl padd asymmetric "" %:.cma
+		 # echo re > authenticated
+
+		The file size of each slot is always 65535 bytes (the maximum
+		size of a certificate chain per SPDM 1.0.0 table 18), even if
+		the certificate chain in the slot is actually smaller.
+
+		Unprovisioned slots are represented as empty files.
+
+		Unsupported slots (introduced by SPDM 1.3 margin no 366) are
+		not visible.  If the device only supports SPDM version 1.2 or
+		earlier, all 8 slots are assumed to be supported and therefore
+		visible.
+
+		The kernel learns which slots are supported when authenticating
+		the device for the first time.  Hence, no slots are visible
+		until at least one authentication attempt has been performed.
+
+		SPDM doesn't support on-demand retrieval of certificate chains,
+		so the kernel caches them when (re-)authenticating the device.
+		SPDM allows provisioning slots behind the kernel's back by
+		sending a SET_CERTIFICATE request through a different transport
+		(e.g. via MCTP from a Baseboard Management Controller).
+		SPDM does not specify how to notify the kernel of such events,
+		so unless reauthentication is manually initiated to update the
+		kernel's cache, the "slot[0-7]" files may contain stale data.
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index d9e467cbec6e..a85388211104 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -1664,6 +1664,7 @@ const struct attribute_group *pci_dev_attr_groups[] = {
 #endif
 #ifdef CONFIG_PCI_CMA
 	&spdm_attr_group,
+	&spdm_certificates_group,
 #endif
 	NULL,
 };
diff --git a/include/linux/spdm.h b/include/linux/spdm.h
index 9835a3202a0e..97c7d4feab76 100644
--- a/include/linux/spdm.h
+++ b/include/linux/spdm.h
@@ -35,5 +35,6 @@ int spdm_authenticate(struct spdm_state *spdm_state);
 void spdm_destroy(struct spdm_state *spdm_state);
 
 extern const struct attribute_group spdm_attr_group;
+extern const struct attribute_group spdm_certificates_group;
 
 #endif
diff --git a/lib/spdm/req-authenticate.c b/lib/spdm/req-authenticate.c
index 90f7a7f2629c..1f701d07ad46 100644
--- a/lib/spdm/req-authenticate.c
+++ b/lib/spdm/req-authenticate.c
@@ -14,6 +14,7 @@
 #include "spdm.h"
 
 #include <linux/dev_printk.h>
+#include <linux/device.h>
 #include <linux/key.h>
 #include <linux/random.h>
 
@@ -288,9 +289,9 @@ static int spdm_get_digests(struct spdm_state *spdm_state)
 	struct spdm_get_digests_req *req = spdm_state->transcript_end;
 	struct spdm_get_digests_rsp *rsp;
 	unsigned long deprovisioned_slots;
+	u8 slot, supported_slots;
 	int rc, length;
 	size_t rsp_sz;
-	u8 slot;
 
 	*req = (struct spdm_get_digests_req) {
 		.code = SPDM_GET_DIGESTS,
@@ -338,6 +339,33 @@ static int spdm_get_digests(struct spdm_state *spdm_state)
 		return -EPROTO;
 	}
 
+	/*
+	 * If a bit is set in ProvisionedSlotMask, the corresponding bit in
+	 * SupportedSlotMask shall also be set (SPDM 1.3.0 table 35).
+	 */
+	if (spdm_state->version >= 0x13 && rsp->param2 & ~rsp->param1) {
+		dev_err(spdm_state->dev, "Malformed digests response\n");
+		return -EPROTO;
+	}
+
+	if (spdm_state->version >= 0x13)
+		supported_slots = rsp->param1;
+	else
+		supported_slots = GENMASK(7, 0);
+
+	if (spdm_state->supported_slots != supported_slots) {
+		spdm_state->supported_slots = supported_slots;
+
+		if (device_is_registered(spdm_state->dev)) {
+			rc = sysfs_update_group(&spdm_state->dev->kobj,
+						&spdm_certificates_group);
+			if (rc)
+				dev_err(spdm_state->dev,
+					"Cannot update certificates in sysfs: "
+					"%d\n", rc);
+		}
+	}
+
 	return 0;
 }
 
diff --git a/lib/spdm/req-sysfs.c b/lib/spdm/req-sysfs.c
index 9bbed7abc153..afba3c5a2e8f 100644
--- a/lib/spdm/req-sysfs.c
+++ b/lib/spdm/req-sysfs.c
@@ -93,3 +93,83 @@ const struct attribute_group spdm_attr_group = {
 	.attrs = spdm_attrs,
 	.is_visible = spdm_attrs_are_visible,
 };
+
+/* certificates attributes */
+
+static umode_t spdm_certificates_are_visible(struct kobject *kobj,
+					     struct bin_attribute *a, int n)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	struct spdm_state *spdm_state = dev_to_spdm_state(dev);
+	u8 slot = a->attr.name[4] - '0';
+
+	if (IS_ERR_OR_NULL(spdm_state))
+		return SYSFS_GROUP_INVISIBLE;
+
+	if (!(spdm_state->supported_slots & BIT(slot)))
+		return 0;
+
+	return a->attr.mode;
+}
+
+static ssize_t spdm_cert_read(struct file *file, struct kobject *kobj,
+			      struct bin_attribute *a, char *buf, loff_t off,
+			      size_t count)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	struct spdm_state *spdm_state = dev_to_spdm_state(dev);
+	u8 slot = a->attr.name[4] - '0';
+	size_t header_size, cert_size;
+
+	/*
+	 * Serialize with spdm_authenticate() as it may change hash_len,
+	 * slot_sz[] and slot[] members in struct spdm_state.
+	 */
+	guard(mutex)(&spdm_state->lock);
+
+	/*
+	 * slot[] is prefixed by the 4 + H header per SPDM 1.0.0 table 15.
+	 * The header is not exposed to user space, only the certificates are.
+	 */
+	header_size = sizeof(struct spdm_cert_chain) + spdm_state->hash_len;
+	cert_size = spdm_state->slot_sz[slot] - header_size;
+
+	if (!spdm_state->slot[slot])
+		return 0;
+	if (!count)
+		return 0;
+	if (off > cert_size)
+		return 0;
+	if (off + count > cert_size)
+		count = cert_size - off;
+
+	memcpy(buf, (u8 *)spdm_state->slot[slot] + header_size + off, count);
+	return count;
+}
+
+static BIN_ATTR(slot0, 0444, spdm_cert_read, NULL, 0xffff);
+static BIN_ATTR(slot1, 0444, spdm_cert_read, NULL, 0xffff);
+static BIN_ATTR(slot2, 0444, spdm_cert_read, NULL, 0xffff);
+static BIN_ATTR(slot3, 0444, spdm_cert_read, NULL, 0xffff);
+static BIN_ATTR(slot4, 0444, spdm_cert_read, NULL, 0xffff);
+static BIN_ATTR(slot5, 0444, spdm_cert_read, NULL, 0xffff);
+static BIN_ATTR(slot6, 0444, spdm_cert_read, NULL, 0xffff);
+static BIN_ATTR(slot7, 0444, spdm_cert_read, NULL, 0xffff);
+
+static struct bin_attribute *spdm_certificates_bin_attrs[] = {
+	&bin_attr_slot0,
+	&bin_attr_slot1,
+	&bin_attr_slot2,
+	&bin_attr_slot3,
+	&bin_attr_slot4,
+	&bin_attr_slot5,
+	&bin_attr_slot6,
+	&bin_attr_slot7,
+	NULL
+};
+
+const struct attribute_group spdm_certificates_group = {
+	.name = "certificates",
+	.bin_attrs = spdm_certificates_bin_attrs,
+	.is_bin_visible = spdm_certificates_are_visible,
+};
diff --git a/lib/spdm/spdm.h b/lib/spdm/spdm.h
index 0992b2bc3942..6c426b2be372 100644
--- a/lib/spdm/spdm.h
+++ b/lib/spdm/spdm.h
@@ -436,6 +436,8 @@ struct spdm_error_rsp {
  * @base_hash_alg: Hash algorithm for signature verification of
  *	CHALLENGE_AUTH messages.
  *	Selected by responder during NEGOTIATE_ALGORITHMS exchange.
+ * @supported_slots: Bitmask of responder's supported certificate slots.
+ *	Received during GET_DIGESTS exchange (from SPDM 1.3).
  * @provisioned_slots: Bitmask of responder's provisioned certificate slots.
  *	Received during GET_DIGESTS exchange.
  * @base_asym_enc: Human-readable name of @base_asym_alg's signature encoding.
@@ -480,6 +482,7 @@ struct spdm_state {
 	u32 rsp_caps;
 	u32 base_asym_alg;
 	u32 base_hash_alg;
+	unsigned long supported_slots;
 	unsigned long provisioned_slots;
 
 	/* Signature algorithm */
