From 366367a7253a2124ed14d9d667c46305a5c3dbbb Mon Sep 17 00:00:00 2001 From: Harald Freudenberger Date: Thu, 24 Apr 2025 15:36:01 +0200 Subject: [PATCH] s390/zcrypt: Introduce cprb mempool for ep11 misc functions Introduce a cprb mempool for the zcrypt ep11 misc functions (zcrypt_ep11misc.*) do some preparation rework to support a do-not-allocate path through some zcrypt ep11 misc functions. The mempool is controlled by the zcrypt module parameter "mempool_threshold" which shall control the minimal amount of memory items for CCA and EP11. The mempool shall support "mempool_threshold" requests/replies in parallel which means for EP11 to hold a send and receive buffer memory per request. Each of this cprb space items is limited to 8 KB. So by default the mempool consumes 5 * 2 * 8KB = 80KB If the mempool is depleted upon one ep11 misc functions is called with the ZCRYPT_XFLAG_NOMEMALLOC xflag set, the function will fail with -ENOMEM and the caller is responsible for taking further actions. This is only part of an rework to support a new xflag ZCRYPT_XFLAG_NOMEMALLOC but not yet complete. Signed-off-by: Harald Freudenberger Reviewed-by: Holger Dengler Link: https://lore.kernel.org/r/20250424133619.16495-8-freude@linux.ibm.com Signed-off-by: Heiko Carstens --- drivers/s390/crypto/zcrypt_api.c | 6 + drivers/s390/crypto/zcrypt_ep11misc.c | 151 +++++++++++++++----------- drivers/s390/crypto/zcrypt_ep11misc.h | 1 + 3 files changed, 96 insertions(+), 62 deletions(-) diff --git a/drivers/s390/crypto/zcrypt_api.c b/drivers/s390/crypto/zcrypt_api.c index 57d819966dad..88bf719b4c58 100644 --- a/drivers/s390/crypto/zcrypt_api.c +++ b/drivers/s390/crypto/zcrypt_api.c @@ -2166,6 +2166,10 @@ int __init zcrypt_api_init(void) if (rc) goto out_ccamisc_init_failed; + rc = zcrypt_ep11misc_init(); + if (rc) + goto out_ep11misc_init_failed; + /* Register the request sprayer. */ rc = misc_register(&zcrypt_misc_device); if (rc < 0) @@ -2177,6 +2181,8 @@ int __init zcrypt_api_init(void) return 0; out_misc_register_failed: + zcrypt_ep11misc_exit(); +out_ep11misc_init_failed: zcrypt_ccamisc_exit(); out_ccamisc_init_failed: zcdn_exit(); diff --git a/drivers/s390/crypto/zcrypt_ep11misc.c b/drivers/s390/crypto/zcrypt_ep11misc.c index b60e262bcaa3..048582851f25 100644 --- a/drivers/s390/crypto/zcrypt_ep11misc.c +++ b/drivers/s390/crypto/zcrypt_ep11misc.c @@ -10,9 +10,10 @@ #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt #include +#include #include -#include #include +#include #include #include #include @@ -30,6 +31,14 @@ static const u8 def_iv[16] = { 0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, 0x99, 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff }; +/* + * Cprb memory pool held for urgent cases where no memory + * can be allocated via kmalloc. This pool is only used when + * alloc_cprbmem() is called with the xflag ZCRYPT_XFLAG_NOMEMALLOC. + */ +#define CPRB_MEMPOOL_ITEM_SIZE (8 * 1024) +static mempool_t *cprb_mempool; + /* ep11 card info cache */ struct card_list_entry { struct list_head list; @@ -411,14 +420,20 @@ EXPORT_SYMBOL(ep11_check_aes_key); /* * Allocate and prepare ep11 cprb plus additional payload. */ -static inline struct ep11_cprb *alloc_cprb(size_t payload_len) +static void *alloc_cprbmem(size_t payload_len, u32 xflags) { size_t len = sizeof(struct ep11_cprb) + payload_len; - struct ep11_cprb *cprb; + struct ep11_cprb *cprb = NULL; - cprb = kzalloc(len, GFP_KERNEL); + if (xflags & ZCRYPT_XFLAG_NOMEMALLOC) { + if (len <= CPRB_MEMPOOL_ITEM_SIZE) + cprb = mempool_alloc_preallocated(cprb_mempool); + } else { + cprb = kmalloc(len, GFP_KERNEL); + } if (!cprb) return NULL; + memset(cprb, 0, len); cprb->cprb_len = sizeof(struct ep11_cprb); cprb->cprb_ver_id = 0x04; @@ -429,6 +444,20 @@ static inline struct ep11_cprb *alloc_cprb(size_t payload_len) return cprb; } +/* + * Free ep11 cprb buffer space. + */ +static void free_cprbmem(void *mem, size_t payload_len, bool scrub, u32 xflags) +{ + if (mem && scrub) + memzero_explicit(mem, sizeof(struct ep11_cprb) + payload_len); + + if (xflags & ZCRYPT_XFLAG_NOMEMALLOC) + mempool_free(mem, cprb_mempool); + else + kfree(mem); +} + /* * Some helper functions related to ASN1 encoding. * Limited to length info <= 2 byte. @@ -489,6 +518,7 @@ static inline void prep_urb(struct ep11_urb *u, struct ep11_cprb *req, size_t req_len, struct ep11_cprb *rep, size_t rep_len) { + memset(u, 0, sizeof(*u)); u->targets = (u8 __user *)t; u->targets_num = nt; u->req = (u8 __user *)req; @@ -605,11 +635,12 @@ static int ep11_query_info(u16 cardnr, u16 domain, u32 query_type, } __packed * rep_pl; struct ep11_cprb *req = NULL, *rep = NULL; struct ep11_target_dev target; - struct ep11_urb *urb = NULL; + struct ep11_urb urb; int api = EP11_API_V1, rc = -ENOMEM; + const u32 xflags = 0; /* request cprb and payload */ - req = alloc_cprb(sizeof(struct ep11_info_req_pl)); + req = alloc_cprbmem(sizeof(struct ep11_info_req_pl), xflags); if (!req) goto out; req_pl = (struct ep11_info_req_pl *)(((u8 *)req) + sizeof(*req)); @@ -621,22 +652,19 @@ static int ep11_query_info(u16 cardnr, u16 domain, u32 query_type, req_pl->query_subtype_len = sizeof(u32); /* reply cprb and payload */ - rep = alloc_cprb(sizeof(struct ep11_info_rep_pl) + buflen); + rep = alloc_cprbmem(sizeof(struct ep11_info_rep_pl) + buflen, xflags); if (!rep) goto out; rep_pl = (struct ep11_info_rep_pl *)(((u8 *)rep) + sizeof(*rep)); /* urb and target */ - urb = kmalloc(sizeof(*urb), GFP_KERNEL); - if (!urb) - goto out; target.ap_id = cardnr; target.dom_id = domain; - prep_urb(urb, &target, 1, + prep_urb(&urb, &target, 1, req, sizeof(*req) + sizeof(*req_pl), rep, sizeof(*rep) + sizeof(*rep_pl) + buflen); - rc = zcrypt_send_ep11_cprb(urb, 0); + rc = zcrypt_send_ep11_cprb(&urb, xflags); if (rc) { ZCRYPT_DBF_ERR("%s zcrypt_send_ep11_cprb(card=%d dom=%d) failed, rc=%d\n", __func__, (int)cardnr, (int)domain, rc); @@ -667,9 +695,8 @@ static int ep11_query_info(u16 cardnr, u16 domain, u32 query_type, memcpy(buf, ((u8 *)rep_pl) + sizeof(*rep_pl), rep_pl->data_len); out: - kfree(req); - kfree(rep); - kfree(urb); + free_cprbmem(req, 0, false, xflags); + free_cprbmem(rep, 0, false, xflags); return rc; } @@ -823,9 +850,10 @@ static int _ep11_genaeskey(u16 card, u16 domain, struct ep11_cprb *req = NULL, *rep = NULL; size_t req_pl_size, pinblob_size = 0; struct ep11_target_dev target; - struct ep11_urb *urb = NULL; + struct ep11_urb urb; int api, rc = -ENOMEM; u8 *p; + const u32 xflags = 0; switch (keybitsize) { case 128: @@ -851,7 +879,7 @@ static int _ep11_genaeskey(u16 card, u16 domain, pinblob_size = EP11_PINBLOB_V1_BYTES; } req_pl_size = sizeof(struct keygen_req_pl) + ASN1TAGLEN(pinblob_size); - req = alloc_cprb(req_pl_size); + req = alloc_cprbmem(req_pl_size, xflags); if (!req) goto out; req_pl = (struct keygen_req_pl *)(((u8 *)req) + sizeof(*req)); @@ -877,22 +905,19 @@ static int _ep11_genaeskey(u16 card, u16 domain, *p++ = pinblob_size; /* reply cprb and payload */ - rep = alloc_cprb(sizeof(struct keygen_rep_pl)); + rep = alloc_cprbmem(sizeof(struct keygen_rep_pl), xflags); if (!rep) goto out; rep_pl = (struct keygen_rep_pl *)(((u8 *)rep) + sizeof(*rep)); /* urb and target */ - urb = kmalloc(sizeof(*urb), GFP_KERNEL); - if (!urb) - goto out; target.ap_id = card; target.dom_id = domain; - prep_urb(urb, &target, 1, + prep_urb(&urb, &target, 1, req, sizeof(*req) + req_pl_size, rep, sizeof(*rep) + sizeof(*rep_pl)); - rc = zcrypt_send_ep11_cprb(urb, 0); + rc = zcrypt_send_ep11_cprb(&urb, xflags); if (rc) { ZCRYPT_DBF_ERR("%s zcrypt_send_ep11_cprb(card=%d dom=%d) failed, rc=%d\n", __func__, (int)card, (int)domain, rc); @@ -925,9 +950,8 @@ static int _ep11_genaeskey(u16 card, u16 domain, *keybufsize = rep_pl->data_len; out: - kfree(req); - kfree(rep); - kfree(urb); + free_cprbmem(req, 0, false, xflags); + free_cprbmem(rep, sizeof(struct keygen_rep_pl), true, xflags); return rc; } @@ -1000,10 +1024,11 @@ static int ep11_cryptsingle(u16 card, u16 domain, } __packed * rep_pl; struct ep11_cprb *req = NULL, *rep = NULL; struct ep11_target_dev target; - struct ep11_urb *urb = NULL; - size_t req_pl_size, rep_pl_size; + struct ep11_urb urb; + size_t req_pl_size, rep_pl_size = 0; int n, api = EP11_API_V1, rc = -ENOMEM; u8 *p; + const u32 xflags = 0; /* the simple asn1 coding used has length limits */ if (keysize > 0xFFFF || inbufsize > 0xFFFF) @@ -1012,7 +1037,7 @@ static int ep11_cryptsingle(u16 card, u16 domain, /* request cprb and payload */ req_pl_size = sizeof(struct crypt_req_pl) + (iv ? 16 : 0) + ASN1TAGLEN(keysize) + ASN1TAGLEN(inbufsize); - req = alloc_cprb(req_pl_size); + req = alloc_cprbmem(req_pl_size, xflags); if (!req) goto out; req_pl = (struct crypt_req_pl *)(((u8 *)req) + sizeof(*req)); @@ -1034,22 +1059,19 @@ static int ep11_cryptsingle(u16 card, u16 domain, /* reply cprb and payload, assume out data size <= in data size + 32 */ rep_pl_size = sizeof(struct crypt_rep_pl) + ASN1TAGLEN(inbufsize + 32); - rep = alloc_cprb(rep_pl_size); + rep = alloc_cprbmem(rep_pl_size, xflags); if (!rep) goto out; rep_pl = (struct crypt_rep_pl *)(((u8 *)rep) + sizeof(*rep)); /* urb and target */ - urb = kmalloc(sizeof(*urb), GFP_KERNEL); - if (!urb) - goto out; target.ap_id = card; target.dom_id = domain; - prep_urb(urb, &target, 1, + prep_urb(&urb, &target, 1, req, sizeof(*req) + req_pl_size, rep, sizeof(*rep) + rep_pl_size); - rc = zcrypt_send_ep11_cprb(urb, 0); + rc = zcrypt_send_ep11_cprb(&urb, xflags); if (rc) { ZCRYPT_DBF_ERR("%s zcrypt_send_ep11_cprb(card=%d dom=%d) failed, rc=%d\n", __func__, (int)card, (int)domain, rc); @@ -1095,9 +1117,8 @@ static int ep11_cryptsingle(u16 card, u16 domain, *outbufsize = n; out: - kfree(req); - kfree(rep); - kfree(urb); + free_cprbmem(req, req_pl_size, true, xflags); + free_cprbmem(rep, rep_pl_size, true, xflags); return rc; } @@ -1143,9 +1164,10 @@ static int _ep11_unwrapkey(u16 card, u16 domain, struct ep11_cprb *req = NULL, *rep = NULL; size_t req_pl_size, pinblob_size = 0; struct ep11_target_dev target; - struct ep11_urb *urb = NULL; + struct ep11_urb urb; int api, rc = -ENOMEM; u8 *p; + const u32 xflags = 0; /* request cprb and payload */ api = (!keygenflags || keygenflags & 0x00200000) ? @@ -1161,7 +1183,7 @@ static int _ep11_unwrapkey(u16 card, u16 domain, req_pl_size = sizeof(struct uw_req_pl) + (iv ? 16 : 0) + ASN1TAGLEN(keksize) + ASN1TAGLEN(0) + ASN1TAGLEN(pinblob_size) + ASN1TAGLEN(enckeysize); - req = alloc_cprb(req_pl_size); + req = alloc_cprbmem(req_pl_size, xflags); if (!req) goto out; req_pl = (struct uw_req_pl *)(((u8 *)req) + sizeof(*req)); @@ -1197,22 +1219,19 @@ static int _ep11_unwrapkey(u16 card, u16 domain, p += asn1tag_write(p, 0x04, enckey, enckeysize); /* reply cprb and payload */ - rep = alloc_cprb(sizeof(struct uw_rep_pl)); + rep = alloc_cprbmem(sizeof(struct uw_rep_pl), xflags); if (!rep) goto out; rep_pl = (struct uw_rep_pl *)(((u8 *)rep) + sizeof(*rep)); /* urb and target */ - urb = kmalloc(sizeof(*urb), GFP_KERNEL); - if (!urb) - goto out; target.ap_id = card; target.dom_id = domain; - prep_urb(urb, &target, 1, + prep_urb(&urb, &target, 1, req, sizeof(*req) + req_pl_size, rep, sizeof(*rep) + sizeof(*rep_pl)); - rc = zcrypt_send_ep11_cprb(urb, 0); + rc = zcrypt_send_ep11_cprb(&urb, xflags); if (rc) { ZCRYPT_DBF_ERR("%s zcrypt_send_ep11_cprb(card=%d dom=%d) failed, rc=%d\n", __func__, (int)card, (int)domain, rc); @@ -1245,9 +1264,8 @@ static int _ep11_unwrapkey(u16 card, u16 domain, *keybufsize = rep_pl->data_len; out: - kfree(req); - kfree(rep); - kfree(urb); + free_cprbmem(req, req_pl_size, true, xflags); + free_cprbmem(rep, sizeof(struct uw_rep_pl), true, xflags); return rc; } @@ -1319,15 +1337,16 @@ static int _ep11_wrapkey(u16 card, u16 domain, } __packed * rep_pl; struct ep11_cprb *req = NULL, *rep = NULL; struct ep11_target_dev target; - struct ep11_urb *urb = NULL; + struct ep11_urb urb; size_t req_pl_size; int api, rc = -ENOMEM; u8 *p; + const u32 xflags = 0; /* request cprb and payload */ req_pl_size = sizeof(struct wk_req_pl) + (iv ? 16 : 0) + ASN1TAGLEN(keysize) + 4; - req = alloc_cprb(req_pl_size); + req = alloc_cprbmem(req_pl_size, xflags); if (!req) goto out; if (!mech || mech == 0x80060001) @@ -1357,22 +1376,19 @@ static int _ep11_wrapkey(u16 card, u16 domain, *p++ = 0; /* reply cprb and payload */ - rep = alloc_cprb(sizeof(struct wk_rep_pl)); + rep = alloc_cprbmem(sizeof(struct wk_rep_pl), xflags); if (!rep) goto out; rep_pl = (struct wk_rep_pl *)(((u8 *)rep) + sizeof(*rep)); /* urb and target */ - urb = kmalloc(sizeof(*urb), GFP_KERNEL); - if (!urb) - goto out; target.ap_id = card; target.dom_id = domain; - prep_urb(urb, &target, 1, + prep_urb(&urb, &target, 1, req, sizeof(*req) + req_pl_size, rep, sizeof(*rep) + sizeof(*rep_pl)); - rc = zcrypt_send_ep11_cprb(urb, 0); + rc = zcrypt_send_ep11_cprb(&urb, xflags); if (rc) { ZCRYPT_DBF_ERR("%s zcrypt_send_ep11_cprb(card=%d dom=%d) failed, rc=%d\n", __func__, (int)card, (int)domain, rc); @@ -1405,9 +1421,8 @@ static int _ep11_wrapkey(u16 card, u16 domain, *datasize = rep_pl->data_len; out: - kfree(req); - kfree(rep); - kfree(urb); + free_cprbmem(req, req_pl_size, true, xflags); + free_cprbmem(rep, sizeof(struct wk_rep_pl), true, xflags); return rc; } @@ -1459,7 +1474,7 @@ int ep11_clr2keyblob(u16 card, u16 domain, u32 keybitsize, u32 keygenflags, encbuf, encbuflen, 0, def_iv, keybitsize, 0, keybuf, keybufsize, keytype); if (rc) { - ZCRYPT_DBF_ERR("%s importing key value as new key failed,, rc=%d\n", + ZCRYPT_DBF_ERR("%s importing key value as new key failed, rc=%d\n", __func__, rc); goto out; } @@ -1658,7 +1673,19 @@ int ep11_findcard2(u32 **apqns, u32 *nr_apqns, u16 cardnr, u16 domain, } EXPORT_SYMBOL(ep11_findcard2); -void __exit zcrypt_ep11misc_exit(void) +int __init zcrypt_ep11misc_init(void) +{ + /* Pre-allocate a small memory pool for ep11 cprbs. */ + cprb_mempool = mempool_create_kmalloc_pool(2 * zcrypt_mempool_threshold, + CPRB_MEMPOOL_ITEM_SIZE); + if (!cprb_mempool) + return -ENOMEM; + + return 0; +} + +void zcrypt_ep11misc_exit(void) { card_cache_free(); + mempool_destroy(cprb_mempool); } diff --git a/drivers/s390/crypto/zcrypt_ep11misc.h b/drivers/s390/crypto/zcrypt_ep11misc.h index 9f1bdffdec68..a4b98eca8431 100644 --- a/drivers/s390/crypto/zcrypt_ep11misc.h +++ b/drivers/s390/crypto/zcrypt_ep11misc.h @@ -152,6 +152,7 @@ int ep11_findcard2(u32 **apqns, u32 *nr_apqns, u16 cardnr, u16 domain, int ep11_kblob2protkey(u16 card, u16 dom, const u8 *key, u32 keylen, u8 *protkey, u32 *protkeylen, u32 *protkeytype); +int zcrypt_ep11misc_init(void); void zcrypt_ep11misc_exit(void); #endif /* _ZCRYPT_EP11MISC_H_ */ -- 2.25.1