Merge tag 'v6.18-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6

Pull crypto updates from Herbert Xu:
 "Drivers:
   - Add ciphertext hiding support to ccp
   - Add hashjoin, gather and UDMA data move features to hisilicon
   - Add lz4 and lz77_only to hisilicon
   - Add xilinx hwrng driver
   - Add ti driver with ecb/cbc aes support
   - Add ring buffer idle and command queue telemetry for GEN6 in qat

  Others:
   - Use rcu_dereference_all to stop false alarms in rhashtable
   - Fix CPU number wraparound in padata"

* tag 'v6.18-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (78 commits)
  dt-bindings: rng: hisi-rng: convert to DT schema
  crypto: doc - Add explicit title heading to API docs
  hwrng: ks-sa - fix division by zero in ks_sa_rng_init
  KEYS: X.509: Fix Basic Constraints CA flag parsing
  crypto: anubis - simplify return statement in anubis_mod_init
  crypto: hisilicon/qm - set NULL to qm->debug.qm_diff_regs
  crypto: hisilicon/qm - clear all VF configurations in the hardware
  crypto: hisilicon - enable error reporting again
  crypto: hisilicon/qm - mask axi error before memory init
  crypto: hisilicon/qm - invalidate queues in use
  crypto: qat - Return pointer directly in adf_ctl_alloc_resources
  crypto: aspeed - Fix dma_unmap_sg() direction
  rhashtable: Use rcu_dereference_all and rcu_dereference_all_check
  crypto: comp - Use same definition of context alloc and free ops
  crypto: omap - convert from tasklet to BH workqueue
  crypto: qat - Replace kzalloc() + copy_from_user() with memdup_user()
  crypto: caam - double the entropy delay interval for retry
  padata: WQ_PERCPU added to alloc_workqueue users
  padata: replace use of system_unbound_wq with system_dfl_wq
  crypto: cryptd - WQ_PERCPU added to alloc_workqueue users
  ...

1 files changed, 12 insertions, 4 deletions

diff --git a/crypto/asymmetric_keys/x509_cert_parser.c b/crypto/asymmetric_keys/x509_cert_parser.c
index 2ffe4ae90bea..8df3fa60a44f 100644
--- a/crypto/asymmetric_keys/x509_cert_parser.c
+++ b/crypto/asymmetric_keys/x509_cert_parser.c
@@ -610,11 +610,14 @@ int x509_process_extension(void *context, size_t hdrlen,
 		/*
 		 * Get hold of the basicConstraints
 		 * v[1] is the encoding size
-		 *	(Expect 0x2 or greater, making it 1 or more bytes)
+		 *	(Expect 0x00 for empty SEQUENCE with CA:FALSE, or
+		 *	0x03 or greater for non-empty SEQUENCE)
 		 * v[2] is the encoding type
 		 *	(Expect an ASN1_BOOL for the CA)
-		 * v[3] is the contents of the ASN1_BOOL
-		 *      (Expect 1 if the CA is TRUE)
+		 * v[3] is the length of the ASN1_BOOL
+		 *	(Expect 1 for a single byte boolean)
+		 * v[4] is the contents of the ASN1_BOOL
+		 *	(Expect 0xFF if the CA is TRUE)
 		 * vlen should match the entire extension size
 		 */
 		if (v[0] != (ASN1_CONS_BIT | ASN1_SEQ))
@@ -623,8 +626,13 @@ int x509_process_extension(void *context, size_t hdrlen,
 			return -EBADMSG;
 		if (v[1] != vlen - 2)
 			return -EBADMSG;
-		if (vlen >= 4 && v[1] != 0 && v[2] == ASN1_BOOL && v[3] == 1)
+		/* Empty SEQUENCE means CA:FALSE (default value omitted per DER) */
+		if (v[1] == 0)
+			return 0;
+		if (vlen >= 5 && v[2] == ASN1_BOOL && v[3] == 1 && v[4] == 0xFF)
 			ctx->cert->pub->key_eflags |= 1 << KEY_EFLAG_CA;
+		else
+			return -EBADMSG;
 		return 0;
 	}