From mboxrd@z Thu Jan 1 00:00:00 1970 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 43AA8C433EF for ; Wed, 4 May 2022 03:36:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344344AbiEDDkQ (ORCPT ); Tue, 3 May 2022 23:40:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43926 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230263AbiEDDkN (ORCPT ); Tue, 3 May 2022 23:40:13 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7194F27FE1 for ; Tue, 3 May 2022 20:36:38 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 20D2AB822B5 for ; Wed, 4 May 2022 03:36:37 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B98D1C385A4; Wed, 4 May 2022 03:36:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1651635395; bh=bjQ56T29VFG1YiPrSmzz+EbcJnsSn4sEHFX27PEqq1g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LkQHU7zu/69j8PnF4dkfXMHs33CzSIHamDndo2w1WA8MfMg+m2U7XK/bZmFmh5sIk wS1KW5uKuGMnx7F1Dl55VH4NW/HPqCpK3zFw4kXzGwpMpoLSMIFdYZfuVox1SsoFNG +wpD7L8taRbBvlahrMt2tFi+mDCs1BQLs0RQM7AjIQ94M5nh97gi2Uu1/k5hfCGVeN SDuY8ytu8pjwYldmGfD7VDAg/u6BRuEtQJCakZdo29DDusgK/80ugozwZtvO6dU/8g VhUQeht2jUzbLtxBde+kCKGxkUXkaY+I7S4Nh9a7TCCqIWC1YfkDVX+IJ/EbLiacPT js+dYjC0npF/w== From: Masami Hiramatsu To: Steven Rostedt Cc: "Naveen N . Rao" , Anil S Keshavamurthy , "David S . Miller" , Masami Hiramatsu , Peter Zijlstra , Max Filippov , linux-kernel@vger.kernel.org Subject: [PATCH] kprobes: Fix build errors with CONFIG_KRETPROBES=n Date: Wed, 4 May 2022 12:36:31 +0900 Message-Id: <165163539094.74407.3838114721073251225.stgit@devnote2> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220502184050.1792743-1-jcmvbkbc@gmail.com> References: <20220502184050.1792743-1-jcmvbkbc@gmail.com> User-Agent: StGit/0.19 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Max Filippov reported: When building kernel with CONFIG_KRETPROBES=n kernel/kprobes.c compilation fails with the following messages: kernel/kprobes.c: In function ‘recycle_rp_inst’: kernel/kprobes.c:1273:32: error: implicit declaration of function ‘get_kretprobe’ kernel/kprobes.c: In function ‘kprobe_flush_task’: kernel/kprobes.c:1299:35: error: ‘struct task_struct’ has no member named ‘kretprobe_instances’ This came from the commit d741bf41d7c7 ("kprobes: Remove kretprobe hash") which introduced get_kretprobe() and kretprobe_instances member in task_struct when CONFIG_KRETPROBES=y, but did not make recycle_rp_inst() and kprobe_flush_task() depending on CONFIG_KRETPORBES. Since those functions are only used for kretprobe, move those functions into #ifdef CONFIG_KRETPROBE area. Reported-by: Max Filippov Fixes: d741bf41d7c7 ("kprobes: Remove kretprobe hash") Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu --- include/linux/kprobes.h | 2 - kernel/kprobes.c | 144 +++++++++++++++++++++++------------------------ 2 files changed, 72 insertions(+), 74 deletions(-) diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h index 157168769fc2..55041d2f884d 100644 --- a/include/linux/kprobes.h +++ b/include/linux/kprobes.h @@ -424,7 +424,7 @@ void unregister_kretprobe(struct kretprobe *rp); int register_kretprobes(struct kretprobe **rps, int num); void unregister_kretprobes(struct kretprobe **rps, int num); -#ifdef CONFIG_KRETPROBE_ON_RETHOOK +#if defined(CONFIG_KRETPROBE_ON_RETHOOK) || !defined(CONFIG_KRETPROBES) #define kprobe_flush_task(tk) do {} while (0) #else void kprobe_flush_task(struct task_struct *tk); diff --git a/kernel/kprobes.c b/kernel/kprobes.c index dd58c0be9ce2..f214f8c088ed 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1257,79 +1257,6 @@ void kprobe_busy_end(void) preempt_enable(); } -#if !defined(CONFIG_KRETPROBE_ON_RETHOOK) -static void free_rp_inst_rcu(struct rcu_head *head) -{ - struct kretprobe_instance *ri = container_of(head, struct kretprobe_instance, rcu); - - if (refcount_dec_and_test(&ri->rph->ref)) - kfree(ri->rph); - kfree(ri); -} -NOKPROBE_SYMBOL(free_rp_inst_rcu); - -static void recycle_rp_inst(struct kretprobe_instance *ri) -{ - struct kretprobe *rp = get_kretprobe(ri); - - if (likely(rp)) - freelist_add(&ri->freelist, &rp->freelist); - else - call_rcu(&ri->rcu, free_rp_inst_rcu); -} -NOKPROBE_SYMBOL(recycle_rp_inst); - -/* - * This function is called from delayed_put_task_struct() when a task is - * dead and cleaned up to recycle any kretprobe instances associated with - * this task. These left over instances represent probed functions that - * have been called but will never return. - */ -void kprobe_flush_task(struct task_struct *tk) -{ - struct kretprobe_instance *ri; - struct llist_node *node; - - /* Early boot, not yet initialized. */ - if (unlikely(!kprobes_initialized)) - return; - - kprobe_busy_begin(); - - node = __llist_del_all(&tk->kretprobe_instances); - while (node) { - ri = container_of(node, struct kretprobe_instance, llist); - node = node->next; - - recycle_rp_inst(ri); - } - - kprobe_busy_end(); -} -NOKPROBE_SYMBOL(kprobe_flush_task); - -static inline void free_rp_inst(struct kretprobe *rp) -{ - struct kretprobe_instance *ri; - struct freelist_node *node; - int count = 0; - - node = rp->freelist.head; - while (node) { - ri = container_of(node, struct kretprobe_instance, freelist); - node = node->next; - - kfree(ri); - count++; - } - - if (refcount_sub_and_test(count, &rp->rph->ref)) { - kfree(rp->rph); - rp->rph = NULL; - } -} -#endif /* !CONFIG_KRETPROBE_ON_RETHOOK */ - /* Add the new probe to 'ap->list'. */ static int add_new_kprobe(struct kprobe *ap, struct kprobe *p) { @@ -1928,6 +1855,77 @@ static struct notifier_block kprobe_exceptions_nb = { #ifdef CONFIG_KRETPROBES #if !defined(CONFIG_KRETPROBE_ON_RETHOOK) +static void free_rp_inst_rcu(struct rcu_head *head) +{ + struct kretprobe_instance *ri = container_of(head, struct kretprobe_instance, rcu); + + if (refcount_dec_and_test(&ri->rph->ref)) + kfree(ri->rph); + kfree(ri); +} +NOKPROBE_SYMBOL(free_rp_inst_rcu); + +static void recycle_rp_inst(struct kretprobe_instance *ri) +{ + struct kretprobe *rp = get_kretprobe(ri); + + if (likely(rp)) + freelist_add(&ri->freelist, &rp->freelist); + else + call_rcu(&ri->rcu, free_rp_inst_rcu); +} +NOKPROBE_SYMBOL(recycle_rp_inst); + +/* + * This function is called from delayed_put_task_struct() when a task is + * dead and cleaned up to recycle any kretprobe instances associated with + * this task. These left over instances represent probed functions that + * have been called but will never return. + */ +void kprobe_flush_task(struct task_struct *tk) +{ + struct kretprobe_instance *ri; + struct llist_node *node; + + /* Early boot, not yet initialized. */ + if (unlikely(!kprobes_initialized)) + return; + + kprobe_busy_begin(); + + node = __llist_del_all(&tk->kretprobe_instances); + while (node) { + ri = container_of(node, struct kretprobe_instance, llist); + node = node->next; + + recycle_rp_inst(ri); + } + + kprobe_busy_end(); +} +NOKPROBE_SYMBOL(kprobe_flush_task); + +static inline void free_rp_inst(struct kretprobe *rp) +{ + struct kretprobe_instance *ri; + struct freelist_node *node; + int count = 0; + + node = rp->freelist.head; + while (node) { + ri = container_of(node, struct kretprobe_instance, freelist); + node = node->next; + + kfree(ri); + count++; + } + + if (refcount_sub_and_test(count, &rp->rph->ref)) { + kfree(rp->rph); + rp->rph = NULL; + } +} + /* This assumes the 'tsk' is the current task or the is not running. */ static kprobe_opcode_t *__kretprobe_find_ret_addr(struct task_struct *tsk, struct llist_node **cur)