From patchwork Mon May 4 11:59:22 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ondrej Mosnacek X-Patchwork-Id: 11525581 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9CCF515AB for ; Mon, 4 May 2020 11:59:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7FFD12073E for ; Mon, 4 May 2020 11:59:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="frsvzteF" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728029AbgEDL7h (ORCPT ); Mon, 4 May 2020 07:59:37 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:52678 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726445AbgEDL7h (ORCPT ); Mon, 4 May 2020 07:59:37 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1588593574; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=OF9aTBqWDlehvSRLyGmnYoSSjhzuzWhtsFPYgubddZs=; b=frsvzteFACbwJZEKJD6yyqKAnPfCwejeHhcsecXqwnaJ7GAHSt5f2eof9mBVreX5IU5nZG 2kbnAzYbGFmqCpD0VyJTIYt4iEYmuL+PY7oVnHnWgt5T9GMdzjfphS32ibaKd1ubyyNK5z FDYDWw4ofquZ7ItybAPIxNoU7C/x4ec= Received: from mail-wr1-f71.google.com (mail-wr1-f71.google.com [209.85.221.71]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-222-Up29GEeqNgmHRhw7oYZo8Q-1; Mon, 04 May 2020 07:59:31 -0400 X-MC-Unique: Up29GEeqNgmHRhw7oYZo8Q-1 Received: by mail-wr1-f71.google.com with SMTP id f15so10681130wrj.2 for ; Mon, 04 May 2020 04:59:31 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=OF9aTBqWDlehvSRLyGmnYoSSjhzuzWhtsFPYgubddZs=; b=nRPT1yLs61SVT8kgr5qgUBNaxOyZWQPcG4JbBy7KivpbecPgj03wR9qq9zNl4hHx8h wpBhHanW8FZRauPGOApHWL/Vz68q8GgITZf0pukdzH8IVgFkyTZSYtnNOCm4BU84WpWP h68lmvIHrXnhd+4gLK1qD+mfk4VNO008OT9hDJPnTlec6d5akYY7WBziHKk4374XDBrz kokB6ZKrRYIjyfTPXDCe1vQveu2wNidvEzT04BBjemGcfwQE3Ae2/Jb6Kg1G5oLi6AYf fP3w9tD6yUkjTssZGRYJ8WakesBy04tpqAKbKJW7Ppi9xn6Zk4pL4Bu5wI/iP8/sv61f w0lw== X-Gm-Message-State: AGi0PuZFdNodI89f2tcWQROy/W/7jFmhohJ6MlomEpI60Fvy1PV6h6jr tB4aubNn9o6vQFwJa4NUzF9Dpm+A2r25BuA/xIQKfcnhGCS/m9hS1iPe74OoCoB1FlFEKwMhY4e OGC9gyYLVyHZP3j3aYA== X-Received: by 2002:a5d:6305:: with SMTP id i5mr21157692wru.60.1588593569279; Mon, 04 May 2020 04:59:29 -0700 (PDT) X-Google-Smtp-Source: APiQypI+R9PBuTKHY2z540zRfQArpB6RwruVG+kwCCEr264NPjWHwamgMM7o4RXtETuERnnsr/7/wg== X-Received: by 2002:a5d:6305:: with SMTP id i5mr21157659wru.60.1588593568826; Mon, 04 May 2020 04:59:28 -0700 (PDT) Received: from omos.redhat.com ([2a02:8308:b13f:2100:f695:3ae5:c8bf:2f57]) by smtp.gmail.com with ESMTPSA id y9sm12524724wmm.26.2020.05.04.04.59.27 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 04 May 2020 04:59:28 -0700 (PDT) From: Ondrej Mosnacek To: selinux@vger.kernel.org, Paul Moore Cc: Stephen Smalley , Stephen Smalley Subject: [PATCH v2 2/3] selinux: prepare for inlining of hashtab functions Date: Mon, 4 May 2020 13:59:22 +0200 Message-Id: <20200504115923.88828-3-omosnace@redhat.com> X-Mailer: git-send-email 2.25.4 In-Reply-To: <20200504115923.88828-1-omosnace@redhat.com> References: <20200504115923.88828-1-omosnace@redhat.com> MIME-Version: 1.0 Sender: selinux-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: selinux@vger.kernel.org Refactor searching and inserting into hashtabs to pave way for converting hashtab_search() and hashtab_insert() to inline functions in the next patch. This will avoid indirect calls and allow the compiler to better optimize individual callers, leading to a drastic performance improvement. In order to avoid the indirect calls, the key hashing and comparison callbacks need to be extracted from the hashtab struct and passed directly to hashtab_search()/_insert() by the callers so that it is always known which callbacks we want to call at compile time. Note that the kernel's rhashtable library () also does the same. This of course makes the hashtab functions more easy to misuse by passing a wrong calback set, but unfortunately there is no better way to implement a hash table that is both generic and efficient in C. This patch tries to somewhat mitigate this by only calling the hashtab functions in the same file where the corresponding callbacks are defined (wrapping them into more specialized functions as needed). Note that this patch doesn't bring any benefit without also defining hashtab_search() and -_insert() inline, which is done in a follow-up patch to make it easier to review the hashtab.c changes here. Signed-off-by: Ondrej Mosnacek --- security/selinux/ss/hashtab.c | 44 ++++++++++---------- security/selinux/ss/hashtab.h | 22 +++++----- security/selinux/ss/mls.c | 2 +- security/selinux/ss/policydb.c | 76 ++++++++++++++++++++++++---------- security/selinux/ss/policydb.h | 9 ++++ security/selinux/ss/services.c | 4 +- security/selinux/ss/symtab.c | 16 ++++--- 7 files changed, 110 insertions(+), 63 deletions(-) diff --git a/security/selinux/ss/hashtab.c b/security/selinux/ss/hashtab.c index 5ee868116d70..8126b909a757 100644 --- a/security/selinux/ss/hashtab.c +++ b/security/selinux/ss/hashtab.c @@ -29,16 +29,10 @@ static u32 hashtab_compute_size(u32 nel) return nel == 0 ? 0 : roundup_pow_of_two(nel); } -int hashtab_init(struct hashtab *h, - u32 (*hash_value)(struct hashtab *h, const void *key), - int (*keycmp)(struct hashtab *h, const void *key1, - const void *key2), - u32 nel_hint) +int hashtab_init(struct hashtab *h, u32 nel_hint) { h->size = hashtab_compute_size(nel_hint); h->nel = 0; - h->hash_value = hash_value; - h->keycmp = keycmp; if (!h->size) return 0; @@ -46,7 +40,8 @@ int hashtab_init(struct hashtab *h, return h->htable ? 0 : -ENOMEM; } -int hashtab_insert(struct hashtab *h, void *key, void *datum) +int hashtab_insert(struct hashtab *h, void *key, void *datum, + struct hashtab_key_params key_params) { u32 hvalue; struct hashtab_node *prev, *cur, *newnode; @@ -56,17 +51,20 @@ int hashtab_insert(struct hashtab *h, void *key, void *datum) if (!h->size || h->nel == HASHTAB_MAX_NODES) return -EINVAL; - hvalue = h->hash_value(h, key); + hvalue = key_params.hash(key) & (h->size - 1); prev = NULL; cur = h->htable[hvalue]; - while (cur && h->keycmp(h, key, cur->key) > 0) { + while (cur) { + int cmp = key_params.cmp(key, cur->key); + + if (cmp == 0) + return -EEXIST; + if (cmp < 0) + break; prev = cur; cur = cur->next; } - if (cur && (h->keycmp(h, key, cur->key) == 0)) - return -EEXIST; - newnode = kmem_cache_zalloc(hashtab_node_cachep, GFP_KERNEL); if (!newnode) return -ENOMEM; @@ -84,7 +82,8 @@ int hashtab_insert(struct hashtab *h, void *key, void *datum) return 0; } -void *hashtab_search(struct hashtab *h, const void *key) +void *hashtab_search(struct hashtab *h, const void *key, + struct hashtab_key_params key_params) { u32 hvalue; struct hashtab_node *cur; @@ -92,15 +91,18 @@ void *hashtab_search(struct hashtab *h, const void *key) if (!h->size) return NULL; - hvalue = h->hash_value(h, key); + hvalue = key_params.hash(key) & (h->size - 1); cur = h->htable[hvalue]; - while (cur && h->keycmp(h, key, cur->key) > 0) - cur = cur->next; + while (cur) { + int cmp = key_params.cmp(key, cur->key); - if (!cur || (h->keycmp(h, key, cur->key) != 0)) - return NULL; - - return cur->datum; + if (cmp == 0) + return cur->datum; + if (cmp < 0) + break; + cur = cur->next; + } + return NULL; } void hashtab_destroy(struct hashtab *h) diff --git a/security/selinux/ss/hashtab.h b/security/selinux/ss/hashtab.h index 31c11511fe10..4885234257d4 100644 --- a/security/selinux/ss/hashtab.h +++ b/security/selinux/ss/hashtab.h @@ -13,6 +13,12 @@ #define HASHTAB_MAX_NODES 0xffffffff +struct hashtab_key_params { + u32 (*hash)(const void *key); /* hash function */ + int (*cmp)(const void *key1, const void *key2); + /* key comparison function */ +}; + struct hashtab_node { void *key; void *datum; @@ -23,10 +29,6 @@ struct hashtab { struct hashtab_node **htable; /* hash table */ u32 size; /* number of slots in hash table */ u32 nel; /* number of elements in hash table */ - u32 (*hash_value)(struct hashtab *h, const void *key); - /* hash function */ - int (*keycmp)(struct hashtab *h, const void *key1, const void *key2); - /* key comparison function */ }; struct hashtab_info { @@ -39,11 +41,7 @@ struct hashtab_info { * * Returns -ENOMEM if insufficient space is available or 0 otherwise. */ -int hashtab_init(struct hashtab *h, - u32 (*hash_value)(struct hashtab *h, const void *key), - int (*keycmp)(struct hashtab *h, const void *key1, - const void *key2), - u32 nel_hint); +int hashtab_init(struct hashtab *h, u32 nel_hint); /* * Inserts the specified (key, datum) pair into the specified hash table. @@ -53,7 +51,8 @@ int hashtab_init(struct hashtab *h, * -EINVAL for general errors or 0 otherwise. */ -int hashtab_insert(struct hashtab *h, void *k, void *d); +int hashtab_insert(struct hashtab *h, void *k, void *d, + struct hashtab_key_params key_params); /* * Searches for the entry with the specified key in the hash table. @@ -61,7 +60,8 @@ int hashtab_insert(struct hashtab *h, void *k, void *d); * Returns NULL if no entry has the specified key or * the datum of the entry otherwise. */ -void *hashtab_search(struct hashtab *h, const void *k); +void *hashtab_search(struct hashtab *h, const void *k, + struct hashtab_key_params key_params); /* * Destroys the specified hash table. diff --git a/security/selinux/ss/mls.c b/security/selinux/ss/mls.c index 5be241b6b190..408d306895f8 100644 --- a/security/selinux/ss/mls.c +++ b/security/selinux/ss/mls.c @@ -507,7 +507,7 @@ int mls_compute_sid(struct policydb *p, rtr.source_type = scontext->type; rtr.target_type = tcontext->type; rtr.target_class = tclass; - r = hashtab_search(&p->range_tr, &rtr); + r = policydb_rangetr_search(p, &rtr); if (r) return mls_range_set(newcontext, r); diff --git a/security/selinux/ss/policydb.c b/security/selinux/ss/policydb.c index 043c7b111399..ee870f1b1010 100644 --- a/security/selinux/ss/policydb.c +++ b/security/selinux/ss/policydb.c @@ -411,7 +411,7 @@ out: return rc; } -static u32 filenametr_hash(struct hashtab *h, const void *k) +static u32 filenametr_hash(const void *k) { const struct filename_trans_key *ft = k; unsigned long hash; @@ -423,10 +423,10 @@ static u32 filenametr_hash(struct hashtab *h, const void *k) byte_num = 0; while ((focus = ft->name[byte_num++])) hash = partial_name_hash(focus, hash); - return hash & (h->size - 1); + return hash; } -static int filenametr_cmp(struct hashtab *h, const void *k1, const void *k2) +static int filenametr_cmp(const void *k1, const void *k2) { const struct filename_trans_key *ft1 = k1; const struct filename_trans_key *ft2 = k2; @@ -444,15 +444,26 @@ static int filenametr_cmp(struct hashtab *h, const void *k1, const void *k2) } -static u32 rangetr_hash(struct hashtab *h, const void *k) +static const struct hashtab_key_params filenametr_key_params = { + .hash = filenametr_hash, + .cmp = filenametr_cmp, +}; + +struct filename_trans_datum *policydb_filenametr_search( + struct policydb *p, struct filename_trans_key *key) +{ + return hashtab_search(&p->filename_trans, key, filenametr_key_params); +} + +static u32 rangetr_hash(const void *k) { const struct range_trans *key = k; - return (key->source_type + (key->target_type << 3) + - (key->target_class << 5)) & (h->size - 1); + return key->source_type + (key->target_type << 3) + + (key->target_class << 5); } -static int rangetr_cmp(struct hashtab *h, const void *k1, const void *k2) +static int rangetr_cmp(const void *k1, const void *k2) { const struct range_trans *key1 = k1, *key2 = k2; int v; @@ -470,15 +481,25 @@ static int rangetr_cmp(struct hashtab *h, const void *k1, const void *k2) return v; } -static u32 role_trans_hash(struct hashtab *h, const void *k) +static const struct hashtab_key_params rangetr_key_params = { + .hash = rangetr_hash, + .cmp = rangetr_cmp, +}; + +struct mls_range *policydb_rangetr_search(struct policydb *p, + struct range_trans *key) +{ + return hashtab_search(&p->range_tr, key, rangetr_key_params); +} + +static u32 role_trans_hash(const void *k) { const struct role_trans_key *key = k; - return (key->role + (key->type << 3) + (key->tclass << 5)) & - (h->size - 1); + return key->role + (key->type << 3) + (key->tclass << 5); } -static int role_trans_cmp(struct hashtab *h, const void *k1, const void *k2) +static int role_trans_cmp(const void *k1, const void *k2) { const struct role_trans_key *key1 = k1, *key2 = k2; int v; @@ -494,6 +515,17 @@ static int role_trans_cmp(struct hashtab *h, const void *k1, const void *k2) return key1->tclass - key2->tclass; } +static const struct hashtab_key_params roletr_key_params = { + .hash = role_trans_hash, + .cmp = role_trans_cmp, +}; + +struct role_trans_datum *policydb_roletr_search(struct policydb *p, + struct role_trans_key *key) +{ + return hashtab_search(&p->role_tr, key, roletr_key_params); +} + /* * Initialize a policy database structure. */ @@ -1796,7 +1828,7 @@ static int range_read(struct policydb *p, void *fp) nel = le32_to_cpu(buf[0]); - rc = hashtab_init(&p->range_tr, rangetr_hash, rangetr_cmp, nel); + rc = hashtab_init(&p->range_tr, nel); if (rc) return rc; @@ -1841,7 +1873,7 @@ static int range_read(struct policydb *p, void *fp) goto out; } - rc = hashtab_insert(&p->range_tr, rt, r); + rc = hashtab_insert(&p->range_tr, rt, r, rangetr_key_params); if (rc) goto out; @@ -1888,7 +1920,7 @@ static int filename_trans_read_helper_compat(struct policydb *p, void *fp) otype = le32_to_cpu(buf[3]); last = NULL; - datum = hashtab_search(&p->filename_trans, &key); + datum = hashtab_search(&p->filename_trans, &key, filenametr_key_params); while (datum) { if (unlikely(ebitmap_get_bit(&datum->stypes, stype - 1))) { /* conflicting/duplicate rules are ignored */ @@ -1918,7 +1950,8 @@ static int filename_trans_read_helper_compat(struct policydb *p, void *fp) if (!ft) goto out; - rc = hashtab_insert(&p->filename_trans, ft, datum); + rc = hashtab_insert(&p->filename_trans, ft, datum, + filenametr_key_params); if (rc) goto out; name = NULL; @@ -2006,7 +2039,8 @@ static int filename_trans_read_helper(struct policydb *p, void *fp) ft->tclass = tclass; ft->name = name; - rc = hashtab_insert(&p->filename_trans, ft, first); + rc = hashtab_insert(&p->filename_trans, ft, first, + filenametr_key_params); if (rc == -EEXIST) pr_err("SELinux: Duplicate filename transition key\n"); if (rc) @@ -2044,8 +2078,7 @@ static int filename_trans_read(struct policydb *p, void *fp) if (p->policyvers < POLICYDB_VERSION_COMP_FTRANS) { p->compat_filename_trans_count = nel; - rc = hashtab_init(&p->filename_trans, filenametr_hash, - filenametr_cmp, (1 << 11)); + rc = hashtab_init(&p->filename_trans, (1 << 11)); if (rc) return rc; @@ -2055,8 +2088,7 @@ static int filename_trans_read(struct policydb *p, void *fp) return rc; } } else { - rc = hashtab_init(&p->filename_trans, filenametr_hash, - filenametr_cmp, nel); + rc = hashtab_init(&p->filename_trans, nel); if (rc) return rc; @@ -2537,7 +2569,7 @@ int policydb_read(struct policydb *p, void *fp) goto bad; nel = le32_to_cpu(buf[0]); - rc = hashtab_init(&p->role_tr, role_trans_hash, role_trans_cmp, nel); + rc = hashtab_init(&p->role_tr, nel); if (rc) goto bad; for (i = 0; i < nel; i++) { @@ -2574,7 +2606,7 @@ int policydb_read(struct policydb *p, void *fp) !policydb_role_isvalid(p, rtd->new_role)) goto bad; - rc = hashtab_insert(&p->role_tr, rtk, rtd); + rc = hashtab_insert(&p->role_tr, rtk, rtd, roletr_key_params); if (rc) goto bad; diff --git a/security/selinux/ss/policydb.h b/security/selinux/ss/policydb.h index 9591c9587cb6..c24d4e1063ea 100644 --- a/security/selinux/ss/policydb.h +++ b/security/selinux/ss/policydb.h @@ -324,6 +324,15 @@ extern int policydb_role_isvalid(struct policydb *p, unsigned int role); extern int policydb_read(struct policydb *p, void *fp); extern int policydb_write(struct policydb *p, void *fp); +extern struct filename_trans_datum *policydb_filenametr_search( + struct policydb *p, struct filename_trans_key *key); + +extern struct mls_range *policydb_rangetr_search( + struct policydb *p, struct range_trans *key); + +extern struct role_trans_datum *policydb_roletr_search( + struct policydb *p, struct role_trans_key *key); + #define POLICYDB_CONFIG_MLS 1 /* the config flags related to unknown classes/perms are bits 2 and 3 */ diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index 1d12bb9ff3dd..9e76a80db6e1 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -1671,7 +1671,7 @@ static void filename_compute_type(struct policydb *policydb, ft.tclass = tclass; ft.name = objname; - datum = hashtab_search(&policydb->filename_trans, &ft); + datum = policydb_filenametr_search(policydb, &ft); while (datum) { if (ebitmap_get_bit(&datum->stypes, stype - 1)) { newcontext->type = datum->otype; @@ -1834,7 +1834,7 @@ static int security_compute_sid(struct selinux_state *state, .tclass = tclass, }; - rtd = hashtab_search(&policydb->role_tr, &rtk); + rtd = policydb_roletr_search(policydb, &rtk); if (rtd) newcontext.role = rtd->new_role; } diff --git a/security/selinux/ss/symtab.c b/security/selinux/ss/symtab.c index 48f523ef93aa..c42a6648a07d 100644 --- a/security/selinux/ss/symtab.c +++ b/security/selinux/ss/symtab.c @@ -9,7 +9,7 @@ #include #include "symtab.h" -static unsigned int symhash(struct hashtab *h, const void *key) +static unsigned int symhash(const void *key) { const char *p, *keyp; unsigned int size; @@ -20,10 +20,10 @@ static unsigned int symhash(struct hashtab *h, const void *key) size = strlen(keyp); for (p = keyp; (p - keyp) < size; p++) val = (val << 4 | (val >> (8*sizeof(unsigned int)-4))) ^ (*p); - return val & (h->size - 1); + return val; } -static int symcmp(struct hashtab *h, const void *key1, const void *key2) +static int symcmp(const void *key1, const void *key2) { const char *keyp1, *keyp2; @@ -32,19 +32,23 @@ static int symcmp(struct hashtab *h, const void *key1, const void *key2) return strcmp(keyp1, keyp2); } +static const struct hashtab_key_params symtab_key_params = { + .hash = symhash, + .cmp = symcmp, +}; int symtab_init(struct symtab *s, unsigned int size) { s->nprim = 0; - return hashtab_init(&s->table, symhash, symcmp, size); + return hashtab_init(&s->table, size); } int symtab_insert(struct symtab *s, char *name, void *datum) { - return hashtab_insert(&s->table, name, datum); + return hashtab_insert(&s->table, name, datum, symtab_key_params); } void *symtab_search(struct symtab *s, const char *name) { - return hashtab_search(&s->table, name); + return hashtab_search(&s->table, name, symtab_key_params); }