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 X-Spam-Level: X-Spam-Status: No, score=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B355CC8300B for ; Tue, 27 Oct 2020 00:46:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7C18A218AC for ; Tue, 27 Oct 2020 00:46:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603759570; bh=OceeY6QE41vNN3LO6sLR3LfqQEOrKWi7nX8CZOQFmuk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Hv2jnxPHA6SMeor/u89GzgnJHnAQP3hjACAeBS+hukY4/dNlJ55WvR3g1gr7yyurb irqN7N3+pkTf3y/e57+HVQeTgTBeYsmwTLFywEpeq9q9UzMQTxee2jCPh5duCa0bgk P1YFvRV31uX8JBAbnrF/g9k/7p7zVMcD3AVoaBzI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2502335AbgJ0AnM (ORCPT ); Mon, 26 Oct 2020 20:43:12 -0400 Received: from mail.kernel.org ([198.145.29.99]:49558 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2409073AbgJZXuR (ORCPT ); Mon, 26 Oct 2020 19:50:17 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6693A20878; Mon, 26 Oct 2020 23:50:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603756217; bh=OceeY6QE41vNN3LO6sLR3LfqQEOrKWi7nX8CZOQFmuk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PTDR2zEaXDTaIt4iufvltZ5Z12q1w4HL6FgSPzfRmJJsTAQg20xQ8mjXkDEHMi73A xwwV9MBTBjtZXrH4EgZVnp6Cxy0Yrr8/ftfghZTnuB/7xe5xkchdO35eNeCFgpCgB3 sbJ3bZzWkt1+5RJ2iEOfIL/Tevm4+sZPcnmrprig= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Masami Hiramatsu , Ingo Molnar , Sasha Levin , linux-ia64@vger.kernel.org Subject: [PATCH AUTOSEL 5.9 057/147] ia64: kprobes: Use generic kretprobe trampoline handler Date: Mon, 26 Oct 2020 19:47:35 -0400 Message-Id: <20201026234905.1022767-57-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20201026234905.1022767-1-sashal@kernel.org> References: <20201026234905.1022767-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Masami Hiramatsu [ Upstream commit e792ff804f49720ce003b3e4c618b5d996256a18 ] Use the generic kretprobe trampoline handler. Don't use framepointer verification. Signed-off-by: Masami Hiramatsu Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/159870606883.1229682.12331813108378725668.stgit@devnote2 Signed-off-by: Sasha Levin --- arch/ia64/kernel/kprobes.c | 77 +------------------------------------- 1 file changed, 2 insertions(+), 75 deletions(-) diff --git a/arch/ia64/kernel/kprobes.c b/arch/ia64/kernel/kprobes.c index 7a7df944d7986..fc1ff8a4d7de6 100644 --- a/arch/ia64/kernel/kprobes.c +++ b/arch/ia64/kernel/kprobes.c @@ -396,83 +396,9 @@ static void kretprobe_trampoline(void) { } -/* - * At this point the target function has been tricked into - * returning into our trampoline. Lookup the associated instance - * and then: - * - call the handler function - * - cleanup by marking the instance as unused - * - long jump back to the original return address - */ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) { - struct kretprobe_instance *ri = NULL; - struct hlist_head *head, empty_rp; - struct hlist_node *tmp; - unsigned long flags, orig_ret_address = 0; - unsigned long trampoline_address = - ((struct fnptr *)kretprobe_trampoline)->ip; - - INIT_HLIST_HEAD(&empty_rp); - kretprobe_hash_lock(current, &head, &flags); - - /* - * It is possible to have multiple instances associated with a given - * task either because an multiple functions in the call path - * have a return probe installed on them, and/or more than one return - * return probe was registered for a target function. - * - * We can handle this because: - * - instances are always inserted at the head of the list - * - when multiple return probes are registered for the same - * function, the first instance's ret_addr will point to the - * real return address, and all the rest will point to - * kretprobe_trampoline - */ - hlist_for_each_entry_safe(ri, tmp, head, hlist) { - if (ri->task != current) - /* another task is sharing our hash bucket */ - continue; - - orig_ret_address = (unsigned long)ri->ret_addr; - if (orig_ret_address != trampoline_address) - /* - * This is the real return address. Any other - * instances associated with this task are for - * other calls deeper on the call stack - */ - break; - } - - regs->cr_iip = orig_ret_address; - - hlist_for_each_entry_safe(ri, tmp, head, hlist) { - if (ri->task != current) - /* another task is sharing our hash bucket */ - continue; - - if (ri->rp && ri->rp->handler) - ri->rp->handler(ri, regs); - - orig_ret_address = (unsigned long)ri->ret_addr; - recycle_rp_inst(ri, &empty_rp); - - if (orig_ret_address != trampoline_address) - /* - * This is the real return address. Any other - * instances associated with this task are for - * other calls deeper on the call stack - */ - break; - } - kretprobe_assert(ri, orig_ret_address, trampoline_address); - - kretprobe_hash_unlock(current, &flags); - - hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) { - hlist_del(&ri->hlist); - kfree(ri); - } + regs->cr_iip = __kretprobe_trampoline_handler(regs, kretprobe_trampoline, NULL); /* * By returning a non-zero value, we are telling * kprobe_handler() that we don't want the post_handler @@ -485,6 +411,7 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, struct pt_regs *regs) { ri->ret_addr = (kprobe_opcode_t *)regs->b0; + ri->fp = NULL; /* Replace the return addr with trampoline addr */ regs->b0 = ((struct fnptr *)kretprobe_trampoline)->ip; -- 2.25.1