bpf: mark a NULL kfunc argument precisegrafted

check_kfunc_arg() allows bpf_register_is_null() for nullable arguments
w/o marking the underlying scalar register precise. Hence a checkpoint
created on such a path would prune against arbitrary scalar value.

Fixes: 3bda08b63670 ("bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)")
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20260904-register-is-null-precise-fixes-v1-5-0f5a360ff15d@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 53 insertions, 0 deletions

diff --git a/net/ceph/crypto.h b/net/ceph/crypto.h
new file mode 100644
index 000000000..3a2ade15a
--- /dev/null
+++ b/net/ceph/crypto.h
@@ -0,0 +1,53 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _FS_CEPH_CRYPTO_H
+#define _FS_CEPH_CRYPTO_H
+
+#include <crypto/sha2.h>
+#include <linux/ceph/types.h>
+#include <linux/ceph/buffer.h>
+
+#define CEPH_MAX_KEY_LEN		32
+#define CEPH_MAX_CON_SECRET_LEN		64
+
+/*
+ * cryptographic secret
+ */
+struct ceph_crypto_key {
+	int type;
+	struct ceph_timespec created;
+	int len;
+	void *key;
+
+	union {
+		struct crypto_sync_skcipher *aes_tfm;
+		struct {
+			struct hmac_sha256_key hmac_key;
+			const struct krb5_enctype *krb5_type;
+			struct crypto_aead *krb5_tfms[3];
+		};
+	};
+};
+
+int ceph_crypto_key_prepare(struct ceph_crypto_key *key,
+			    const u32 *key_usages, int key_usage_cnt);
+int ceph_crypto_key_clone(struct ceph_crypto_key *dst,
+			  const struct ceph_crypto_key *src);
+int ceph_crypto_key_decode(struct ceph_crypto_key *key, void **p, void *end);
+int ceph_crypto_key_unarmor(struct ceph_crypto_key *key, const char *in);
+void ceph_crypto_key_destroy(struct ceph_crypto_key *key);
+
+/* crypto.c */
+int ceph_crypt(const struct ceph_crypto_key *key, int usage_slot, bool encrypt,
+	       void *buf, int buf_len, int in_len, int *pout_len);
+int ceph_crypt_data_offset(const struct ceph_crypto_key *key);
+int ceph_crypt_buflen(const struct ceph_crypto_key *key, int data_len);
+void ceph_hmac_sha256(const struct ceph_crypto_key *key, const void *buf,
+		      int buf_len, u8 hmac[SHA256_DIGEST_SIZE]);
+int ceph_crypto_init(void);
+void ceph_crypto_shutdown(void);
+
+/* armor.c */
+int ceph_armor(char *dst, const char *src, const char *end);
+int ceph_unarmor(char *dst, const char *src, const char *end);
+
+#endif