From patchwork Wed Oct 18 17:57:34 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jacob Satterfield X-Patchwork-Id: 13427648 X-Patchwork-Delegate: paul@paul-moore.com Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 76F82CDB483 for ; Wed, 18 Oct 2023 17:59:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232369AbjJRR7b (ORCPT ); Wed, 18 Oct 2023 13:59:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42738 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232042AbjJRR7L (ORCPT ); Wed, 18 Oct 2023 13:59:11 -0400 Received: from mail-qk1-x72d.google.com (mail-qk1-x72d.google.com [IPv6:2607:f8b0:4864:20::72d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7C6E219AC for ; Wed, 18 Oct 2023 10:58:43 -0700 (PDT) Received: by mail-qk1-x72d.google.com with SMTP id af79cd13be357-7788ebea620so102865485a.3 for ; Wed, 18 Oct 2023 10:58:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1697651922; x=1698256722; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=QteVyWxaDl25wYgiD43SEQkNLNzkK7UcKwoMmAAEl5w=; b=WRNCWzmQ06x90Q/TpqJsfex2tEjwaBbhwYTkRC7OrW4ZoMklylsmxMrpDJTJqp4ens Dq7qtlttWUQCP0RHHXCEVTfu+ws7RbF57TMU3TwyZgZTDaB7wuT/9Bu7sToQw5x0xrwt vKjXO0MtJTg3tzZLPgr1E2rItWPrVhsRZzTrw/ezqx48NSCQHM55ZNBTbP9ob6MoUSUv N9LBSPEdSMjD+YsGogBNVixFcZfTDB1PfBugTUqqEf4+o6mk8EdcqC3GR6hKMRf3xAkc Sp+nd5NTKaNLUMGZfkIF7DjkVgymy8Wyw+NcRyRpZAyCQdaN9/aHBpKJ9mjhVyIjklcs 4MmA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697651922; x=1698256722; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=QteVyWxaDl25wYgiD43SEQkNLNzkK7UcKwoMmAAEl5w=; b=Ok2/p17/pxtWZ3JS6jOnfxBXhTKN7v9VBqFuQYLEhx+2lkhYyOyXao33bqynpiGrAu wUUVdsd2Bkb9ha5Q3Re949x4ZN5Mxvyewr8FCSzcSa9sA4pQM7i4LmEChcE8g3b6AV2f u31O4/kJCtc5MuD/fczLmqb2pHH0svGUjHw7dl6AESVDtDGoD1SmQPdms8zrE2UuLLwU yqd2/6p+Ij73piYXayqmWzlwfnZGZaan3Ug7BPj9vmqhG1c7zHhaJsYst7FzNPWl+2O2 FWfwx+FQnuiy+P+WVmYF85+GPM0kCL2XSnLR5Fz913CkpEq7fRF59qz1hSQHK7DeexkZ /iiw== X-Gm-Message-State: AOJu0YzxQLbc+bXCeHtQXONmMKSTY1voNtmn23y0C7s9nrYx/PaLep1v YnmlkGMJ08q9ozJXbokL+9SyWv+c59s= X-Google-Smtp-Source: AGHT+IFtsfVaj1VFwgIW0mqdMxbTqr3rlVd1WhWqX2fN6No3P8bdjH9O+Rev388Nd92+Ph9S6braKQ== X-Received: by 2002:a05:6214:2582:b0:658:71e1:5490 with SMTP id fq2-20020a056214258200b0065871e15490mr6846105qvb.21.1697651921960; Wed, 18 Oct 2023 10:58:41 -0700 (PDT) Received: from 5bc235456ce7.evoforge.org (ec2-52-70-167-183.compute-1.amazonaws.com. [52.70.167.183]) by smtp.gmail.com with ESMTPSA id k15-20020a0cfa4f000000b00655d711180dsm133289qvo.17.2023.10.18.10.58.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 18 Oct 2023 10:58:41 -0700 (PDT) From: Jacob Satterfield To: selinux@vger.kernel.org Cc: Jacob Satterfield , stephen.smalley.work@gmail.com, paul@paul-moore.com, omosnace@redhat.com Subject: [PATCH v3 1/3] selinux: refactor avtab_node comparisons Date: Wed, 18 Oct 2023 17:57:34 +0000 Message-ID: <20231018175744.39667-2-jsatterfield.linux@gmail.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20231018175744.39667-1-jsatterfield.linux@gmail.com> References: <20231018175744.39667-1-jsatterfield.linux@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: selinux@vger.kernel.org In four separate functions within avtab, the same comparison logic is used. The only difference is how the result is handled or whether there is a unique specifier value to be checked for or used. Extracting this functionality into the avtab_node_cmp() function unifies the comparison logic between searching and insertion and gets rid of duplicative code so that the implementation is easier to maintain. Signed-off-by: Jacob Satterfield Reviewed-by: Stephen Smalley --- security/selinux/ss/avtab.c | 101 +++++++++++++++--------------------- 1 file changed, 41 insertions(+), 60 deletions(-) diff --git a/security/selinux/ss/avtab.c b/security/selinux/ss/avtab.c index 8751a602ead2..697eb4352439 100644 --- a/security/selinux/ss/avtab.c +++ b/security/selinux/ss/avtab.c @@ -96,12 +96,34 @@ avtab_insert_node(struct avtab *h, struct avtab_node **dst, return newnode; } +static int avtab_node_cmp(const struct avtab_key *key1, + const struct avtab_key *key2) +{ + u16 specified = key1->specified & ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD); + + if (key1->source_type == key2->source_type && + key1->target_type == key2->target_type && + key1->target_class == key2->target_class && + (specified & key2->specified)) + return 0; + if (key1->source_type < key2->source_type) + return -1; + if (key1->source_type == key2->source_type && + key1->target_type < key2->target_type) + return -1; + if (key1->source_type == key2->source_type && + key1->target_type == key2->target_type && + key1->target_class < key2->target_class) + return -1; + return 1; +} + static int avtab_insert(struct avtab *h, const struct avtab_key *key, const struct avtab_datum *datum) { u32 hvalue; struct avtab_node *prev, *cur, *newnode; - u16 specified = key->specified & ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD); + int cmp; if (!h || !h->nslot || h->nel == U32_MAX) return -EINVAL; @@ -110,23 +132,11 @@ static int avtab_insert(struct avtab *h, const struct avtab_key *key, for (prev = NULL, cur = h->htable[hvalue]; cur; prev = cur, cur = cur->next) { - if (key->source_type == cur->key.source_type && - key->target_type == cur->key.target_type && - key->target_class == cur->key.target_class && - (specified & cur->key.specified)) { - /* extended perms may not be unique */ - if (specified & AVTAB_XPERMS) - break; + cmp = avtab_node_cmp(key, &cur->key); + /* extended perms may not be unique */ + if (cmp == 0 && !(key->specified & AVTAB_XPERMS)) return -EEXIST; - } - if (key->source_type < cur->key.source_type) - break; - if (key->source_type == cur->key.source_type && - key->target_type < cur->key.target_type) - break; - if (key->source_type == cur->key.source_type && - key->target_type == cur->key.target_type && - key->target_class < cur->key.target_class) + if (cmp <= 0) break; } @@ -148,7 +158,7 @@ struct avtab_node *avtab_insert_nonunique(struct avtab *h, { u32 hvalue; struct avtab_node *prev, *cur; - u16 specified = key->specified & ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD); + int cmp; if (!h || !h->nslot || h->nel == U32_MAX) return NULL; @@ -156,19 +166,8 @@ struct avtab_node *avtab_insert_nonunique(struct avtab *h, for (prev = NULL, cur = h->htable[hvalue]; cur; prev = cur, cur = cur->next) { - if (key->source_type == cur->key.source_type && - key->target_type == cur->key.target_type && - key->target_class == cur->key.target_class && - (specified & cur->key.specified)) - break; - if (key->source_type < cur->key.source_type) - break; - if (key->source_type == cur->key.source_type && - key->target_type < cur->key.target_type) - break; - if (key->source_type == cur->key.source_type && - key->target_type == cur->key.target_type && - key->target_class < cur->key.target_class) + cmp = avtab_node_cmp(key, &cur->key); + if (cmp <= 0) break; } return avtab_insert_node(h, prev ? &prev->next : &h->htable[hvalue], @@ -183,7 +182,7 @@ struct avtab_node *avtab_search_node(struct avtab *h, { u32 hvalue; struct avtab_node *cur; - u16 specified = key->specified & ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD); + int cmp; if (!h || !h->nslot) return NULL; @@ -191,20 +190,10 @@ struct avtab_node *avtab_search_node(struct avtab *h, hvalue = avtab_hash(key, h->mask); for (cur = h->htable[hvalue]; cur; cur = cur->next) { - if (key->source_type == cur->key.source_type && - key->target_type == cur->key.target_type && - key->target_class == cur->key.target_class && - (specified & cur->key.specified)) + cmp = avtab_node_cmp(key, &cur->key); + if (cmp == 0) return cur; - - if (key->source_type < cur->key.source_type) - break; - if (key->source_type == cur->key.source_type && - key->target_type < cur->key.target_type) - break; - if (key->source_type == cur->key.source_type && - key->target_type == cur->key.target_type && - key->target_class < cur->key.target_class) + if (cmp < 0) break; } return NULL; @@ -213,27 +202,19 @@ struct avtab_node *avtab_search_node(struct avtab *h, struct avtab_node* avtab_search_node_next(struct avtab_node *node, u16 specified) { + struct avtab_key tmp_key; struct avtab_node *cur; + int cmp; if (!node) return NULL; - - specified &= ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD); + tmp_key = node->key; + tmp_key.specified = specified; for (cur = node->next; cur; cur = cur->next) { - if (node->key.source_type == cur->key.source_type && - node->key.target_type == cur->key.target_type && - node->key.target_class == cur->key.target_class && - (specified & cur->key.specified)) + cmp = avtab_node_cmp(&tmp_key, &cur->key); + if (cmp == 0) return cur; - - if (node->key.source_type < cur->key.source_type) - break; - if (node->key.source_type == cur->key.source_type && - node->key.target_type < cur->key.target_type) - break; - if (node->key.source_type == cur->key.source_type && - node->key.target_type == cur->key.target_type && - node->key.target_class < cur->key.target_class) + if (cmp < 0) break; } return NULL; From patchwork Wed Oct 18 17:57:35 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jacob Satterfield X-Patchwork-Id: 13427649 X-Patchwork-Delegate: paul@paul-moore.com Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4FDFFCDB482 for ; Wed, 18 Oct 2023 17:59:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232761AbjJRR7c (ORCPT ); Wed, 18 Oct 2023 13:59:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60828 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232729AbjJRR7N (ORCPT ); Wed, 18 Oct 2023 13:59:13 -0400 Received: from mail-qv1-xf34.google.com (mail-qv1-xf34.google.com [IPv6:2607:f8b0:4864:20::f34]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7546312C for ; 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[52.70.167.183]) by smtp.gmail.com with ESMTPSA id k15-20020a0cfa4f000000b00655d711180dsm133289qvo.17.2023.10.18.10.58.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 18 Oct 2023 10:58:44 -0700 (PDT) From: Jacob Satterfield To: selinux@vger.kernel.org Cc: Jacob Satterfield , stephen.smalley.work@gmail.com, paul@paul-moore.com, omosnace@redhat.com Subject: [PATCH v3 2/3] selinux: avtab iteration macros Date: Wed, 18 Oct 2023 17:57:35 +0000 Message-ID: <20231018175744.39667-3-jsatterfield.linux@gmail.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20231018175744.39667-1-jsatterfield.linux@gmail.com> References: <20231018175744.39667-1-jsatterfield.linux@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: selinux@vger.kernel.org Similar to the list_for_each macros in list.h, this patch adds two macros that iterates an avtab_node linked list (avtab_chain_for_each and avtab_chain_for_each_prev). This has two benefits: it reduces the amount of duplicative code for iteration and it makes changes to the underlying hashtable data structure easier as there are fewer places to update. Signed-off-by: Jacob Satterfield --- security/selinux/ss/avtab.c | 28 ++++++++++++---------------- 1 file changed, 12 insertions(+), 16 deletions(-) diff --git a/security/selinux/ss/avtab.c b/security/selinux/ss/avtab.c index 697eb4352439..f0d448e7807a 100644 --- a/security/selinux/ss/avtab.c +++ b/security/selinux/ss/avtab.c @@ -27,6 +27,13 @@ static struct kmem_cache *avtab_node_cachep __ro_after_init; static struct kmem_cache *avtab_xperms_cachep __ro_after_init; +#define avtab_chain_for_each(pos, tab, slot) \ + for (pos = (tab)->htable[slot]; pos; pos = pos->next) + +#define avtab_chain_for_each_prev(pos, prev, tab, slot) \ + for (prev = NULL, pos = (tab)->htable[slot]; pos; \ + prev = pos, pos = pos->next) + /* Based on MurmurHash3, written by Austin Appleby and placed in the * public domain. */ @@ -129,9 +136,7 @@ static int avtab_insert(struct avtab *h, const struct avtab_key *key, return -EINVAL; hvalue = avtab_hash(key, h->mask); - for (prev = NULL, cur = h->htable[hvalue]; - cur; - prev = cur, cur = cur->next) { + avtab_chain_for_each_prev(cur, prev, h, hvalue) { cmp = avtab_node_cmp(key, &cur->key); /* extended perms may not be unique */ if (cmp == 0 && !(key->specified & AVTAB_XPERMS)) @@ -163,9 +168,7 @@ struct avtab_node *avtab_insert_nonunique(struct avtab *h, if (!h || !h->nslot || h->nel == U32_MAX) return NULL; hvalue = avtab_hash(key, h->mask); - for (prev = NULL, cur = h->htable[hvalue]; - cur; - prev = cur, cur = cur->next) { + avtab_chain_for_each_prev(cur, prev, h, hvalue) { cmp = avtab_node_cmp(key, &cur->key); if (cmp <= 0) break; @@ -180,16 +183,13 @@ struct avtab_node *avtab_insert_nonunique(struct avtab *h, struct avtab_node *avtab_search_node(struct avtab *h, const struct avtab_key *key) { - u32 hvalue; struct avtab_node *cur; int cmp; if (!h || !h->nslot) return NULL; - hvalue = avtab_hash(key, h->mask); - for (cur = h->htable[hvalue]; cur; - cur = cur->next) { + avtab_chain_for_each(cur, h, avtab_hash(key, h->mask)) { cmp = avtab_node_cmp(key, &cur->key); if (cmp == 0) return cur; @@ -229,7 +229,6 @@ void avtab_destroy(struct avtab *h) return; for (i = 0; i < h->nslot; i++) { - cur = h->htable[i]; while (cur) { temp = cur; cur = cur->next; @@ -307,10 +306,8 @@ void avtab_hash_eval(struct avtab *h, const char *tag) if (cur) { slots_used++; chain_len = 0; - while (cur) { + avtab_chain_for_each(cur, h, i) chain_len++; - cur = cur->next; - } if (chain_len > max_chain_len) max_chain_len = chain_len; @@ -593,8 +590,7 @@ int avtab_write(struct policydb *p, struct avtab *a, void *fp) return rc; for (i = 0; i < a->nslot; i++) { - for (cur = a->htable[i]; cur; - cur = cur->next) { + avtab_chain_for_each(cur, a, i) { rc = avtab_write_item(p, cur, fp); if (rc) return rc; From patchwork Wed Oct 18 17:57:36 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jacob Satterfield X-Patchwork-Id: 13427650 X-Patchwork-Delegate: paul@paul-moore.com Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4DF4ACDB47E for ; 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[52.70.167.183]) by smtp.gmail.com with ESMTPSA id k15-20020a0cfa4f000000b00655d711180dsm133289qvo.17.2023.10.18.10.58.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 18 Oct 2023 10:58:46 -0700 (PDT) From: Jacob Satterfield To: selinux@vger.kernel.org Cc: Jacob Satterfield , stephen.smalley.work@gmail.com, paul@paul-moore.com, omosnace@redhat.com Subject: [PATCH v3 3/3] selinux: use arrays for avtab hashtable nodes Date: Wed, 18 Oct 2023 17:57:36 +0000 Message-ID: <20231018175744.39667-4-jsatterfield.linux@gmail.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20231018175744.39667-1-jsatterfield.linux@gmail.com> References: <20231018175744.39667-1-jsatterfield.linux@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: selinux@vger.kernel.org The current avtab hashtable employs a separate chaining collision resolution strategy where each bucket/chain holds an ordered linked list of pointers to kmem_cache allocated avtab_node elements. On Fedora 38 (x86_64) using the default policy, avtab_node_cachep uses 573 slabs each containing 170 objects totaling 2,337,840 bytes. A call to kmem_cache_zalloc() is required for every single rule, which in the default policy is currently 96,730 and continually rising. When both sets of avtab_node (regular and cond.) are turned into arrays with the hash table slot indexing into it rather than a pointer, then this results in only 2 additional kvcalloc() calls and the complete removal of the kmem_cache itself. Due to how conditional rules are written in the binary policy, the code responsible for loading does not know how many conditional rules there are before creating the avtab structure. Instead, it was using the number of elements in the non-conditional avtab as a hint and allocates the hash table based on it. Therefore, a two-pass algorithm is now used to calculate the rule count before allocating the avtab nodes array. With the current refpolicy and default Fedora policy, this causes the number of hash slots for the conditional array to become 4096 instead of 32768. This results in a savings of 224KB of heap memory. The caching characteristics of iterating a single array are better due to locality of reference. Running "perf stat -r 100 -d load_policy" has shown a runtime reduction of around 10% on a Fedora 38 x86_64 VM with this single patch. Future patches focused on improving the hash table's collision resolution strategy and array layout (struct-of-arrays vs. array-of-structs) may elicit even more caching and therefore runtime performance improvements. Signed-off-by: Jacob Satterfield Reviewed-by: Stephen Smalley --- security/selinux/ss/avtab.c | 47 ++++++++++++++++++++----------- security/selinux/ss/avtab.h | 4 ++- security/selinux/ss/conditional.c | 37 ++++++++++++++++-------- security/selinux/ss/conditional.h | 2 +- 4 files changed, 59 insertions(+), 31 deletions(-) diff --git a/security/selinux/ss/avtab.c b/security/selinux/ss/avtab.c index f0d448e7807a..aabe04fc4d04 100644 --- a/security/selinux/ss/avtab.c +++ b/security/selinux/ss/avtab.c @@ -24,7 +24,6 @@ #include "avtab.h" #include "policydb.h" -static struct kmem_cache *avtab_node_cachep __ro_after_init; static struct kmem_cache *avtab_xperms_cachep __ro_after_init; #define avtab_chain_for_each(pos, tab, slot) \ @@ -79,17 +78,15 @@ avtab_insert_node(struct avtab *h, struct avtab_node **dst, { struct avtab_node *newnode; struct avtab_extended_perms *xperms; - newnode = kmem_cache_zalloc(avtab_node_cachep, GFP_KERNEL); - if (newnode == NULL) + if (h->nel == h->nnodes) return NULL; + newnode = &h->nodes[h->nel]; newnode->key = *key; if (key->specified & AVTAB_XPERMS) { xperms = kmem_cache_zalloc(avtab_xperms_cachep, GFP_KERNEL); - if (xperms == NULL) { - kmem_cache_free(avtab_node_cachep, newnode); + if (xperms == NULL) return NULL; - } *xperms = *(datum->u.xperms); newnode->datum.u.xperms = xperms; } else { @@ -235,11 +232,13 @@ void avtab_destroy(struct avtab *h) if (temp->key.specified & AVTAB_XPERMS) kmem_cache_free(avtab_xperms_cachep, temp->datum.u.xperms); - kmem_cache_free(avtab_node_cachep, temp); } } kvfree(h->htable); + kvfree(h->nodes); h->htable = NULL; + h->nodes = NULL; + h->nnodes = 0; h->nel = 0; h->nslot = 0; h->mask = 0; @@ -248,20 +247,28 @@ void avtab_destroy(struct avtab *h) void avtab_init(struct avtab *h) { h->htable = NULL; + h->nodes = NULL; + h->nnodes = 0; h->nel = 0; h->nslot = 0; h->mask = 0; } -static int avtab_alloc_common(struct avtab *h, u32 nslot) +static int avtab_alloc_common(struct avtab *h, u32 nslot, u32 nrules) { if (!nslot) return 0; - h->htable = kvcalloc(nslot, sizeof(void *), GFP_KERNEL); + h->htable = kvcalloc(nslot, sizeof(*h->htable), GFP_KERNEL); if (!h->htable) return -ENOMEM; - + h->nodes = kvcalloc(nrules, sizeof(*h->nodes), GFP_KERNEL); + if (!h->nodes) { + kvfree(h->htable); + h->htable = NULL; + return -ENOMEM; + } + h->nnodes = nrules; h->nslot = nslot; h->mask = nslot - 1; return 0; @@ -277,7 +284,7 @@ int avtab_alloc(struct avtab *h, u32 nrules) if (nslot > MAX_AVTAB_HASH_BUCKETS) nslot = MAX_AVTAB_HASH_BUCKETS; - rc = avtab_alloc_common(h, nslot); + rc = avtab_alloc_common(h, nslot, nrules); if (rc) return rc; } @@ -288,7 +295,7 @@ int avtab_alloc(struct avtab *h, u32 nrules) int avtab_alloc_dup(struct avtab *new, const struct avtab *orig) { - return avtab_alloc_common(new, orig->nslot); + return avtab_alloc_common(new, orig->nslot, orig->nel); } #ifdef CONFIG_SECURITY_SELINUX_DEBUG @@ -337,7 +344,7 @@ static const uint16_t spec_order[] = { int avtab_read_item(struct avtab *a, void *fp, struct policydb *pol, int (*insertf)(struct avtab *a, const struct avtab_key *k, const struct avtab_datum *d, void *p), - void *p) + void *p, u32 *nrules) { __le16 buf16[4]; u16 enabled; @@ -411,6 +418,10 @@ int avtab_read_item(struct avtab *a, void *fp, struct policydb *pol, if (val & spec_order[i]) { key.specified = spec_order[i] | enabled; datum.u.data = le32_to_cpu(buf32[items++]); + if (nrules) { + (*nrules)++; + continue; + } rc = insertf(a, &key, &datum, p); if (rc) return rc; @@ -489,6 +500,11 @@ int avtab_read_item(struct avtab *a, void *fp, struct policydb *pol, pr_err("SELinux: avtab: invalid type\n"); return -EINVAL; } + + if (nrules) { + (*nrules)++; + return 0; + } return insertf(a, &key, &datum, p); } @@ -522,7 +538,7 @@ int avtab_read(struct avtab *a, void *fp, struct policydb *pol) goto bad; for (i = 0; i < nel; i++) { - rc = avtab_read_item(a, fp, pol, avtab_insertf, NULL); + rc = avtab_read_item(a, fp, pol, avtab_insertf, NULL, NULL); if (rc) { if (rc == -ENOMEM) pr_err("SELinux: avtab: out of memory\n"); @@ -602,9 +618,6 @@ int avtab_write(struct policydb *p, struct avtab *a, void *fp) void __init avtab_cache_init(void) { - avtab_node_cachep = kmem_cache_create("avtab_node", - sizeof(struct avtab_node), - 0, SLAB_PANIC, NULL); avtab_xperms_cachep = kmem_cache_create("avtab_extended_perms", sizeof(struct avtab_extended_perms), 0, SLAB_PANIC, NULL); diff --git a/security/selinux/ss/avtab.h b/security/selinux/ss/avtab.h index 3c3904bf02b0..5e465be6f057 100644 --- a/security/selinux/ss/avtab.h +++ b/security/selinux/ss/avtab.h @@ -82,6 +82,8 @@ struct avtab_node { struct avtab { struct avtab_node **htable; + struct avtab_node *nodes; + u32 nnodes; /* number of nodes */ u32 nel; /* number of elements */ u32 nslot; /* number of hash slots */ u32 mask; /* mask to compute hash func */ @@ -104,7 +106,7 @@ struct policydb; int avtab_read_item(struct avtab *a, void *fp, struct policydb *pol, int (*insert)(struct avtab *a, const struct avtab_key *k, const struct avtab_datum *d, void *p), - void *p); + void *p, u32 *nrules); int avtab_read(struct avtab *a, void *fp, struct policydb *pol); int avtab_write_item(struct policydb *p, const struct avtab_node *cur, void *fp); diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c index 81ff676f209a..bbd35b35b79d 100644 --- a/security/selinux/ss/conditional.c +++ b/security/selinux/ss/conditional.c @@ -140,7 +140,7 @@ void cond_policydb_init(struct policydb *p) static void cond_node_destroy(struct cond_node *node) { kfree(node->expr.nodes); - /* the avtab_ptr_t nodes are destroyed by the avtab */ + /* the actual nodes were destroyed by avtab_destroy() */ kfree(node->true_list.nodes); kfree(node->false_list.nodes); } @@ -323,7 +323,8 @@ static int cond_insertf(struct avtab *a, const struct avtab_key *k, static int cond_read_av_list(struct policydb *p, void *fp, struct cond_av_list *list, - struct cond_av_list *other) + struct cond_av_list *other, + u32 *nrules) { int rc; __le32 buf[1]; @@ -347,7 +348,7 @@ static int cond_read_av_list(struct policydb *p, void *fp, for (i = 0; i < len; i++) { data.dst = &list->nodes[i]; rc = avtab_read_item(&p->te_cond_avtab, fp, p, cond_insertf, - &data); + &data, nrules); if (rc) { kfree(list->nodes); list->nodes = NULL; @@ -373,7 +374,8 @@ static int expr_node_isvalid(struct policydb *p, struct cond_expr_node *expr) return 1; } -static int cond_read_node(struct policydb *p, struct cond_node *node, void *fp) +static int cond_read_node(struct policydb *p, struct cond_node *node, + void *fp, u32 *nrules) { __le32 buf[2]; u32 i, len; @@ -407,16 +409,17 @@ static int cond_read_node(struct policydb *p, struct cond_node *node, void *fp) return -EINVAL; } - rc = cond_read_av_list(p, fp, &node->true_list, NULL); + rc = cond_read_av_list(p, fp, &node->true_list, NULL, nrules); if (rc) return rc; - return cond_read_av_list(p, fp, &node->false_list, &node->true_list); + return cond_read_av_list(p, fp, &node->false_list, &node->true_list, nrules); } -int cond_read_list(struct policydb *p, void *fp) +int cond_read_list(struct policydb *p, struct policy_file *fp) { __le32 buf[1]; - u32 i, len; + struct policy_file tmp_fp; + u32 i, len, nrules; int rc; rc = next_entry(buf, fp, sizeof(buf)); @@ -428,15 +431,25 @@ int cond_read_list(struct policydb *p, void *fp) p->cond_list = kcalloc(len, sizeof(*p->cond_list), GFP_KERNEL); if (!p->cond_list) return -ENOMEM; + p->cond_list_len = len; + + /* first pass to only calculate the avrule count */ + tmp_fp = *fp; + nrules = 0; + for (i = 0; i < len; i++) { + rc = cond_read_node(p, &p->cond_list[i], &tmp_fp, &nrules); + if (rc) + goto err; + cond_node_destroy(&p->cond_list[i]); + } - rc = avtab_alloc(&(p->te_cond_avtab), p->te_avtab.nel); + rc = avtab_alloc(&(p->te_cond_avtab), nrules); if (rc) goto err; - p->cond_list_len = len; - + /* second pass to read in the conditional nodes */ for (i = 0; i < len; i++) { - rc = cond_read_node(p, &p->cond_list[i], fp); + rc = cond_read_node(p, &p->cond_list[i], fp, NULL); if (rc) goto err; } diff --git a/security/selinux/ss/conditional.h b/security/selinux/ss/conditional.h index 5a7b51278dc6..62a12d00cac9 100644 --- a/security/selinux/ss/conditional.h +++ b/security/selinux/ss/conditional.h @@ -70,7 +70,7 @@ int cond_destroy_bool(void *key, void *datum, void *p); int cond_index_bool(void *key, void *datum, void *datap); int cond_read_bool(struct policydb *p, struct symtab *s, void *fp); -int cond_read_list(struct policydb *p, void *fp); +int cond_read_list(struct policydb *p, struct policy_file *fp); int cond_write_bool(void *key, void *datum, void *ptr); int cond_write_list(struct policydb *p, void *fp);