From patchwork Fri Apr 8 00:50:47 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 12805979 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 14C25C433F5 for ; Fri, 8 Apr 2022 00:52:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=kmsW4Bc2MeYlsa8ablcRTPeoIE0EFmw7Q2AEOiPSocA=; b=f3AqfCDgjdkjDq F9ifoYKALEWTq9vMtWwXGwgmVcBoevjufLOwkOHtrPwKvaU3B51/6nTOkSu6fSG+4EudjUjO3v+H+ JkPAXJSNyJNtFR1YG5HcIGk+TUFGax7wke6boCkM3M7blWqmQOQovjHutu3AUa1TYZrVZcS1QDI2G tTB+qO/1jlV+sGyHZXy4oNWqtS6QMg1GNMmpiqAQY1fY4g3O3spUinXMeAFrc4UP1eTrorw79ZLcr bK7oCTk8gmqtU7qUv4xMDRod70BP9qusLTzuJDZRtxesiEWHYqS4JlWneUS5qArbZEF9pzOYZUyx5 StliYfZxW6x9wtj0abAw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nccq6-00ESxp-3G; Fri, 08 Apr 2022 00:51:02 +0000 Received: from ams.source.kernel.org ([145.40.68.75]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nccq2-00ESvw-JX for linux-arm-kernel@lists.infradead.org; Fri, 08 Apr 2022 00:51:00 +0000 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 E8841B826CF; Fri, 8 Apr 2022 00:50:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 41A4BC385A4; Fri, 8 Apr 2022 00:50:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1649379054; bh=Fnq1dNA08/LWYoTGEL2vJKKrr5mYlJKc9c+6cJld2N0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cnLqp19VtblguBhMSGIxaseONA8r+Rcy9/cwcGcdd80faI2m/zBLxathG3BLtF31m 5jWu7pGSjxdbrBizkNsGJoQjC1d84csnLXM/Z1JiMN2sx2fFUA6jl2i8CKvtAqWo8E c0yL3edWumVdK0k/ExKbh97aW1aLS65EETQgVVIRk81Ig4NXLi9Ce8VxSiIQ4Kf7al ZL/iLEr59ZpuPyO0U4L2/hKptkS3VRPV1I+gA8QtisHxH44S5Fvd8D0Bxw27yAJk48 ylMdDcuEO4NEigfp2aStHDz3DrYIxZQ+7E02TUG6S9FTYC/waGjTvAR6z67tczPpjH 3YFy0tvYvDjuw== From: Masami Hiramatsu To: Alexei Starovoitov , Alexei Starovoitov Cc: Daniel Borkmann , Shubham Bansal , Andrii Nakryiko , Masami Hiramatsu , bpf@vger.kernel.org, kernel-team@fb.com, Jiri Olsa , Steven Rostedt , "Naveen N . Rao" , Anil S Keshavamurthy , "David S . Miller" , linux-kernel@vger.kernel.org, Mark Rutland , Will Deacon , Ard Biesheuvel , Russell King , Catalin Marinas , linux-arm-kernel@lists.infradead.org Subject: [PATCH bpf v2 1/4] ARM: unwind: Initialize the lr_addr field of unwind_ctrl_block Date: Fri, 8 Apr 2022 09:50:47 +0900 Message-Id: <164937904755.1272679.25073555823596728.stgit@devnote2> X-Mailer: git-send-email 2.25.1 In-Reply-To: <164937903547.1272679.7244379141135199176.stgit@devnote2> References: <164937903547.1272679.7244379141135199176.stgit@devnote2> User-Agent: StGit/0.19 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220407_175058_839914_27FC11F9 X-CRM114-Status: GOOD ( 12.33 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Since the unwind_ctrl_block::lr_addr is finally passed to stackframe::lr_addr, that value will be exposed unconditionally. Thus it should be initialized. Without this fix, when unwind_frame() doesn't update the unwind_ctrl_block::lr_addr (e.g. 'lr' register is not saved in the target function), stackframe::lr_addr will contain a wrong value. Signed-off-by: Masami Hiramatsu --- Changes in v2: - Initialize pointer by NULL instead of 0. --- arch/arm/kernel/unwind.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm/kernel/unwind.c b/arch/arm/kernel/unwind.c index a37ea6c772cd..c9f719e1b350 100644 --- a/arch/arm/kernel/unwind.c +++ b/arch/arm/kernel/unwind.c @@ -404,6 +404,7 @@ int unwind_frame(struct stackframe *frame) ctrl.vrs[SP] = frame->sp; ctrl.vrs[LR] = frame->lr; ctrl.vrs[PC] = 0; + ctrl.lr_addr = NULL; if (idx->insn == 1) /* can't unwind */ From patchwork Fri Apr 8 00:51:00 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 12805980 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id BA9D4C433EF for ; Fri, 8 Apr 2022 00:52:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=l+oDOBY+QEJYmBd6aEPsK/vW8+Tl0eusHg58+dFQ0J0=; b=mHqHsBsBhNCjXp eq+N5des41XKsDURvm9vKkrm27t9KqPD8AdfZ/WOA/v8O/ge7oWycIAB8B2zcbNoEMU9H7dce8uyN 8QvVyWssiNV0hdeU1/r6ATCsHVKL6gnbMQWI8DHieC8JsRF1np2ypXrheKWpEBEU+dswPJ5+41gvj rvI9gtOkhbQhbmTMVM+EDzNGt0ctU3oGI/eTc1OK/A8R01sTW7TtQ+YBAJQEfItbiI5X6tSuc1bts amU/HNlAyOHmiBwCgYA7vMR7KGMQHF+WmPrfJNNKOqLjHAOAsIl3Qt25HdXYugyBZ1Itp0zSJzd5R k91ZxRPR11uE9umpC67g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nccqG-00ET19-3J; Fri, 08 Apr 2022 00:51:12 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nccqB-00ESzf-T8 for linux-arm-kernel@lists.infradead.org; Fri, 08 Apr 2022 00:51:09 +0000 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 dfw.source.kernel.org (Postfix) with ESMTPS id 73010617F1; Fri, 8 Apr 2022 00:51:07 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 92372C385A9; Fri, 8 Apr 2022 00:51:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1649379066; bh=qU7NQO8a/GNTqpF3kK+hxQlG2bDuw47+HzlGrFENsk0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GOQSPJ8bHkuyeDVLE6PnkAGeUamFLQFl8cos02fJ8bIyktW4ZeXboUeddgG/NMIa2 CaNnuHS++W12Ut17ouCCXqwYJ+xzcmWBztMK5sTWcpSG2jxXAhAPiqn3n3qyVGs5RI DEX5EtMR9GxZz4fdnpitv3nanTaZj3/2+A6vWsYXPUWdbqzEHpBZmqz6Zntz34tHA7 C5LMwWG4dgQH311WFakZVAhou+Sh0SvqdPRsCt6Y3c6wmsRt18XcHRxwCox1tw8pDO criUsaXqR8aM7fK2H+qWAIoPJsfFGnFNwrCMX4p5DabHPNtmE4VZMAFZZAQqElfIOi 92WbAySEbNahQ== From: Masami Hiramatsu To: Alexei Starovoitov , Alexei Starovoitov Cc: Daniel Borkmann , Shubham Bansal , Andrii Nakryiko , Masami Hiramatsu , bpf@vger.kernel.org, kernel-team@fb.com, Jiri Olsa , Steven Rostedt , "Naveen N . Rao" , Anil S Keshavamurthy , "David S . Miller" , linux-kernel@vger.kernel.org, Mark Rutland , Will Deacon , Ard Biesheuvel , Russell King , Catalin Marinas , linux-arm-kernel@lists.infradead.org Subject: [PATCH bpf v2 2/4] rethook, fprobe, kprobes: Check a failure in the rethook_hook() Date: Fri, 8 Apr 2022 09:51:00 +0900 Message-Id: <164937905999.1272679.6572597960911139308.stgit@devnote2> X-Mailer: git-send-email 2.25.1 In-Reply-To: <164937903547.1272679.7244379141135199176.stgit@devnote2> References: <164937903547.1272679.7244379141135199176.stgit@devnote2> User-Agent: StGit/0.19 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220407_175108_078170_F458FF0A X-CRM114-Status: GOOD ( 19.23 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Since there are possible to fail to hook the function return (depends on archtecutre implememtation), rethook_hook() should return the error in that case and caller must check it. Signed-off-by: Masami Hiramatsu --- arch/x86/kernel/rethook.c | 4 +++- include/linux/rethook.h | 4 ++-- kernel/kprobes.c | 8 +++++--- kernel/trace/fprobe.c | 5 ++++- kernel/trace/rethook.c | 12 ++++++++++-- 5 files changed, 24 insertions(+), 9 deletions(-) diff --git a/arch/x86/kernel/rethook.c b/arch/x86/kernel/rethook.c index 8a1c0111ae79..c92b4875e3b9 100644 --- a/arch/x86/kernel/rethook.c +++ b/arch/x86/kernel/rethook.c @@ -114,7 +114,7 @@ void arch_rethook_fixup_return(struct pt_regs *regs, } NOKPROBE_SYMBOL(arch_rethook_fixup_return); -void arch_rethook_prepare(struct rethook_node *rh, struct pt_regs *regs, bool mcount) +int arch_rethook_prepare(struct rethook_node *rh, struct pt_regs *regs, bool mcount) { unsigned long *stack = (unsigned long *)regs->sp; @@ -123,5 +123,7 @@ void arch_rethook_prepare(struct rethook_node *rh, struct pt_regs *regs, bool mc /* Replace the return addr with trampoline addr */ stack[0] = (unsigned long) arch_rethook_trampoline; + + return 0; } NOKPROBE_SYMBOL(arch_rethook_prepare); diff --git a/include/linux/rethook.h b/include/linux/rethook.h index c8ac1e5afcd1..07b9c6663b8e 100644 --- a/include/linux/rethook.h +++ b/include/linux/rethook.h @@ -63,12 +63,12 @@ void rethook_free(struct rethook *rh); void rethook_add_node(struct rethook *rh, struct rethook_node *node); struct rethook_node *rethook_try_get(struct rethook *rh); void rethook_recycle(struct rethook_node *node); -void rethook_hook(struct rethook_node *node, struct pt_regs *regs, bool mcount); +int rethook_hook(struct rethook_node *node, struct pt_regs *regs, bool mcount); unsigned long rethook_find_ret_addr(struct task_struct *tsk, unsigned long frame, struct llist_node **cur); /* Arch dependent code must implement arch_* and trampoline code */ -void arch_rethook_prepare(struct rethook_node *node, struct pt_regs *regs, bool mcount); +int arch_rethook_prepare(struct rethook_node *node, struct pt_regs *regs, bool mcount); void arch_rethook_trampoline(void); /** diff --git a/kernel/kprobes.c b/kernel/kprobes.c index dbe57df2e199..7fd7f1195bde 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -2109,10 +2109,12 @@ static int pre_handler_kretprobe(struct kprobe *p, struct pt_regs *regs) ri = container_of(rhn, struct kretprobe_instance, node); - if (rp->entry_handler && rp->entry_handler(ri, regs)) + if (rp->entry_handler && rp->entry_handler(ri, regs)) { rethook_recycle(rhn); - else - rethook_hook(rhn, regs, kprobe_ftrace(p)); + } else if (rethook_hook(rhn, regs, kprobe_ftrace(p)) < 0) { + rethook_recycle(rhn); + rp->nmissed++; + } return 0; } diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c index 89d9f994ebb0..d3b13294d545 100644 --- a/kernel/trace/fprobe.c +++ b/kernel/trace/fprobe.c @@ -48,7 +48,10 @@ static void fprobe_handler(unsigned long ip, unsigned long parent_ip, } fpr = container_of(rh, struct fprobe_rethook_node, node); fpr->entry_ip = ip; - rethook_hook(rh, ftrace_get_regs(fregs), true); + if (rethook_hook(rh, ftrace_get_regs(fregs), true) < 0) { + rethook_recycle(rh); + fp->nmissed++; + } } out: diff --git a/kernel/trace/rethook.c b/kernel/trace/rethook.c index b56833700d23..e7db83438e45 100644 --- a/kernel/trace/rethook.c +++ b/kernel/trace/rethook.c @@ -174,11 +174,19 @@ NOKPROBE_SYMBOL(rethook_try_get); * from ftrace (mcount) callback, @mcount must be set true. If this is called * from the real function entry (e.g. kprobes) @mcount must be set false. * This is because the way to hook the function return depends on the context. + * This returns 0 if succeeded to hook the function return, or -errno if + * failed. */ -void rethook_hook(struct rethook_node *node, struct pt_regs *regs, bool mcount) +int rethook_hook(struct rethook_node *node, struct pt_regs *regs, bool mcount) { - arch_rethook_prepare(node, regs, mcount); + int ret; + + ret = arch_rethook_prepare(node, regs, mcount); + if (ret < 0) + return ret; + __llist_add(&node->llist, ¤t->rethooks); + return 0; } NOKPROBE_SYMBOL(rethook_hook); From patchwork Fri Apr 8 00:51:12 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 12805981 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E3A69C433F5 for ; Fri, 8 Apr 2022 00:53:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=X1Br9xQtbCBdXuVR4TdAneZbDfGGBmaJ498UUTAAIKE=; b=Buy+axssFE7wu7 i/jrcyqfx7tHVF+k0GbKSgvHS/PXGq+OVYYMQ65ujqby+fm+jbrMRMhyKhbJwbcPRrfyggjEiHOZR YE/tnh1oIl5F8iEyKSnaMiljHJKPauedLq7RSu7tnv/9cGDvp6FdToZ2GcNONKlgTx2TVEMiUoFOs hXYWZ76Y5DPQRo5sbu4Yh4XZQt8yNZOA8Q11XVRI7SoAUqepIQzpHSTUdRO+24bTJSEOr7RjmRvR5 hsfYF8+YvKQQLN43NXxEEzCS0szFnQpAkElpT9snIPc2j0lgBSoX3ErXUuV7uKw001MFx1kUyOdp4 abJAN2ooiK09cAb8iaxw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nccqW-00ET96-Hy; Fri, 08 Apr 2022 00:51:28 +0000 Received: from ams.source.kernel.org ([145.40.68.75]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nccqP-00ET4z-Rb for linux-arm-kernel@lists.infradead.org; Fri, 08 Apr 2022 00:51:25 +0000 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 45404B829B0; Fri, 8 Apr 2022 00:51:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3021FC385A0; Fri, 8 Apr 2022 00:51:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1649379078; bh=DJ+njldE9mf6+hXxlLJj7g6JAs+wj5yBeocMdaJxtKI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=g6RV7Da+RlQjRNA3sg6s9M9sOFjDbYtt7VDOJ7IZ15DOEW0BA3Q+YiYWuR+k0IkUB M3qiVaVKfDILr9EeTRqpXPhTBu0+2BRK/79LHR0QJawXwJhq2/zH7vvD1EpHAstG3A mcHFCP+BT70CpjqzhcFKq+4XytTA0tyEoe7jMEJe8WHBSTkPzFvcJHCOSrGPrz1Cua jgTQMrt8O1x3s5W8LW4rp8ztbEv9Ir3+Tq2zJ9jR+i0BTWvN+WWB81lA6D9UYL8VPf QfMmIIUmidBsQp/SICsYeuY1SLTtXkDKMzx2yk+6/4+w0d8Xv8ZzdSHW3hi6QW2iA5 dBZ3leDpD5uGA== From: Masami Hiramatsu To: Alexei Starovoitov , Alexei Starovoitov Cc: Daniel Borkmann , Shubham Bansal , Andrii Nakryiko , Masami Hiramatsu , bpf@vger.kernel.org, kernel-team@fb.com, Jiri Olsa , Steven Rostedt , "Naveen N . Rao" , Anil S Keshavamurthy , "David S . Miller" , linux-kernel@vger.kernel.org, Mark Rutland , Will Deacon , Ard Biesheuvel , Russell King , Catalin Marinas , linux-arm-kernel@lists.infradead.org Subject: [PATCH bpf v2 3/4] ARM: rethook: Replace kretprobe trampoline with rethook Date: Fri, 8 Apr 2022 09:51:12 +0900 Message-Id: <164937907228.1272679.14692871670063551372.stgit@devnote2> X-Mailer: git-send-email 2.25.1 In-Reply-To: <164937903547.1272679.7244379141135199176.stgit@devnote2> References: <164937903547.1272679.7244379141135199176.stgit@devnote2> User-Agent: StGit/0.19 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220407_175122_235908_669AA959 X-CRM114-Status: GOOD ( 34.86 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Replace the kretprob's trampoline code with the rethook on arm. This also enables rethook support on arm. Most of the code has been copied from kretprobe on arm. The significant difference is that the rethook on mcount (ftrace) support is added. If the rethook is called from the kprobes for kretprobe, there is no problem to replace the LR register with trampoline address because the LR register will be saved after kprobe probed. However, the mcount call will be placed right after making a stack frame for the function. This means we have to decode the stackframe to find where the LR register is saved. With the CONFIG_FRAME_POINTER, the frame pointer (FP register) is used. Without that, rethook has to unwind one stack frame to find it. Signed-off-by: Masami Hiramatsu --- arch/arm/Kconfig | 1 arch/arm/include/asm/stacktrace.h | 5 + arch/arm/kernel/stacktrace.c | 13 ++-- arch/arm/probes/Makefile | 1 arch/arm/probes/kprobes/core.c | 62 ------------------ arch/arm/probes/rethook.c | 127 +++++++++++++++++++++++++++++++++++++ 6 files changed, 139 insertions(+), 70 deletions(-) create mode 100644 arch/arm/probes/rethook.c diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 2e8091e2d8a8..f7054ba596ba 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -110,6 +110,7 @@ config ARM select HAVE_MOD_ARCH_SPECIFIC select HAVE_NMI select HAVE_OPTPROBES if !THUMB2_KERNEL + select HAVE_RETHOOK select HAVE_PERF_EVENTS select HAVE_PERF_REGS select HAVE_PERF_USER_STACK_DUMP diff --git a/arch/arm/include/asm/stacktrace.h b/arch/arm/include/asm/stacktrace.h index 3e78f921b8b2..76a70b25863e 100644 --- a/arch/arm/include/asm/stacktrace.h +++ b/arch/arm/include/asm/stacktrace.h @@ -17,7 +17,8 @@ struct stackframe { /* address of the LR value on the stack */ unsigned long *lr_addr; -#ifdef CONFIG_KRETPROBES + +#if defined(CONFIG_RETHOOK) struct llist_node *kr_cur; struct task_struct *tsk; #endif @@ -30,7 +31,7 @@ void arm_get_current_stackframe(struct pt_regs *regs, struct stackframe *frame) frame->sp = regs->ARM_sp; frame->lr = regs->ARM_lr; frame->pc = regs->ARM_pc; -#ifdef CONFIG_KRETPROBES +#if defined(CONFIG_RETHOOK) frame->kr_cur = NULL; frame->tsk = current; #endif diff --git a/arch/arm/kernel/stacktrace.c b/arch/arm/kernel/stacktrace.c index b5efecb3d730..6df085ecdf41 100644 --- a/arch/arm/kernel/stacktrace.c +++ b/arch/arm/kernel/stacktrace.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: GPL-2.0-only #include #include +#include #include #include #include @@ -66,10 +67,10 @@ int notrace unwind_frame(struct stackframe *frame) frame->sp = *(unsigned long *)(fp - 8); frame->pc = *(unsigned long *)(fp - 4); #endif -#ifdef CONFIG_KRETPROBES - if (is_kretprobe_trampoline(frame->pc)) - frame->pc = kretprobe_find_ret_addr(frame->tsk, - (void *)frame->fp, &frame->kr_cur); +#ifdef CONFIG_RETHOOK + if (is_rethook_trampoline(frame->pc)) + frame->pc = rethook_find_ret_addr(frame->tsk, frame->fp, + &frame->kr_cur); #endif return 0; @@ -163,7 +164,7 @@ static noinline void __save_stack_trace(struct task_struct *tsk, here: frame.pc = (unsigned long)&&here; } -#ifdef CONFIG_KRETPROBES +#ifdef CONFIG_RETHOOK frame.kr_cur = NULL; frame.tsk = tsk; #endif @@ -184,7 +185,7 @@ void save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace) frame.sp = regs->ARM_sp; frame.lr = regs->ARM_lr; frame.pc = regs->ARM_pc; -#ifdef CONFIG_KRETPROBES +#ifdef CONFIG_RETHOOK frame.kr_cur = NULL; frame.tsk = current; #endif diff --git a/arch/arm/probes/Makefile b/arch/arm/probes/Makefile index 8b0ea5ace100..10c083a22223 100644 --- a/arch/arm/probes/Makefile +++ b/arch/arm/probes/Makefile @@ -6,3 +6,4 @@ obj-$(CONFIG_KPROBES) += decode-thumb.o else obj-$(CONFIG_KPROBES) += decode-arm.o endif +obj-$(CONFIG_RETHOOK) += rethook.o diff --git a/arch/arm/probes/kprobes/core.c b/arch/arm/probes/kprobes/core.c index 9090c3a74dcc..2f01f8267cc3 100644 --- a/arch/arm/probes/kprobes/core.c +++ b/arch/arm/probes/kprobes/core.c @@ -365,68 +365,6 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self, return NOTIFY_DONE; } -/* - * When a retprobed function returns, trampoline_handler() is called, - * calling the kretprobe's handler. We construct a struct pt_regs to - * give a view of registers r0-r11, sp, lr, and pc to the user - * return-handler. This is not a complete pt_regs structure, but that - * should be enough for stacktrace from the return handler with or - * without pt_regs. - */ -void __naked __kprobes __kretprobe_trampoline(void) -{ - __asm__ __volatile__ ( -#ifdef CONFIG_FRAME_POINTER - "ldr lr, =__kretprobe_trampoline \n\t" - /* __kretprobe_trampoline makes a framepointer on pt_regs. */ -#ifdef CONFIG_CC_IS_CLANG - "stmdb sp, {sp, lr, pc} \n\t" - "sub sp, sp, #12 \n\t" - /* In clang case, pt_regs->ip = lr. */ - "stmdb sp!, {r0 - r11, lr} \n\t" - /* fp points regs->r11 (fp) */ - "add fp, sp, #44 \n\t" -#else /* !CONFIG_CC_IS_CLANG */ - /* In gcc case, pt_regs->ip = fp. */ - "stmdb sp, {fp, sp, lr, pc} \n\t" - "sub sp, sp, #16 \n\t" - "stmdb sp!, {r0 - r11} \n\t" - /* fp points regs->r15 (pc) */ - "add fp, sp, #60 \n\t" -#endif /* CONFIG_CC_IS_CLANG */ -#else /* !CONFIG_FRAME_POINTER */ - "sub sp, sp, #16 \n\t" - "stmdb sp!, {r0 - r11} \n\t" -#endif /* CONFIG_FRAME_POINTER */ - "mov r0, sp \n\t" - "bl trampoline_handler \n\t" - "mov lr, r0 \n\t" - "ldmia sp!, {r0 - r11} \n\t" - "add sp, sp, #16 \n\t" -#ifdef CONFIG_THUMB2_KERNEL - "bx lr \n\t" -#else - "mov pc, lr \n\t" -#endif - : : : "memory"); -} - -/* Called from __kretprobe_trampoline */ -static __used __kprobes void *trampoline_handler(struct pt_regs *regs) -{ - return (void *)kretprobe_trampoline_handler(regs, (void *)regs->ARM_fp); -} - -void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, - struct pt_regs *regs) -{ - ri->ret_addr = (kprobe_opcode_t *)regs->ARM_lr; - ri->fp = (void *)regs->ARM_fp; - - /* Replace the return addr with trampoline addr. */ - regs->ARM_lr = (unsigned long)&__kretprobe_trampoline; -} - int __kprobes arch_trampoline_kprobe(struct kprobe *p) { return 0; diff --git a/arch/arm/probes/rethook.c b/arch/arm/probes/rethook.c new file mode 100644 index 000000000000..598a2b579b91 --- /dev/null +++ b/arch/arm/probes/rethook.c @@ -0,0 +1,127 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * arm implementation of rethook. Mostly copied from arch/arm/probes/kprobes/core.c + */ + +#include +#include + +#include + +/* Called from arch_rethook_trampoline */ +static __used notrace unsigned long arch_rethook_trampoline_callback(struct pt_regs *regs) +{ + return rethook_trampoline_handler(regs, regs->ARM_fp); +} +NOKPROBE_SYMBOL(arch_rethook_trampoline_callback); + +/* + * When a rethook'ed function returns, it returns to arch_rethook_trampoline + * which calls rethook callback. We construct a struct pt_regs to + * give a view of registers r0-r11, sp, lr, and pc to the user + * return-handler. This is not a complete pt_regs structure, but that + * should be enough for stacktrace from the return handler with or + * without pt_regs. + */ +asm( + ".text\n" + ".global arch_rethook_trampoline\n" + ".type arch_rethook_trampoline, %function\n" + "arch_rethook_trampoline:\n" +#ifdef CONFIG_FRAME_POINTER + "adr lr, . \n\t" + /* this makes a framepointer on pt_regs. */ +#ifdef CONFIG_CC_IS_CLANG + "stmdb sp, {sp, lr, pc} \n\t" + "sub sp, sp, #12 \n\t" + /* In clang case, pt_regs->ip = lr. */ + "stmdb sp!, {r0 - r11, lr} \n\t" + /* fp points regs->r11 (fp) */ + "add fp, sp, #44 \n\t" +#else /* !CONFIG_CC_IS_CLANG */ + /* In gcc case, pt_regs->ip = fp. */ + "stmdb sp, {fp, sp, lr, pc} \n\t" + "sub sp, sp, #16 \n\t" + "stmdb sp!, {r0 - r11} \n\t" + /* fp points regs->r15 (pc) */ + "add fp, sp, #60 \n\t" +#endif /* CONFIG_CC_IS_CLANG */ +#else /* !CONFIG_FRAME_POINTER */ + "sub sp, sp, #16 \n\t" + "stmdb sp!, {r0 - r11} \n\t" +#endif /* CONFIG_FRAME_POINTER */ + "mov r0, sp \n\t" + "bl arch_rethook_trampoline_callback \n\t" + "mov lr, r0 \n\t" + "ldmia sp!, {r0 - r11} \n\t" + "add sp, sp, #16 \n\t" +#ifdef CONFIG_THUMB2_KERNEL + "bx lr \n\t" +#else + "mov pc, lr \n\t" +#endif + ".size arch_rethook_trampoline, .-arch_rethook_trampoline\n" +); +NOKPROBE_SYMBOL(arch_rethook_trampoline); + +/* + * At the entry of function with mcount, if the FRAME_POINTER is enabled, + * the stack and registers are prepared for the mcount function as below. + * + * mov ip, sp + * push {fp, ip, lr, pc} + * sub fp, ip, #4 ; FP[0] = PC, FP[-4] = LR, and FP[-12] = call-site FP. + * push {lr} + * bl <__gnu_mcount_nc> ; call ftrace + * + * And when returning from the function, call-site FP, SP and PC are restored + * from stack as below; + * + * ldm sp, {fp, sp, pc} + * + * Thus, if the arch_rethook_prepare() is called from real function entry, + * it must change the LR and save FP in pt_regs. But if it is called via + * mcount context (ftrace), it must change the LR on stack, which is next + * to the PC (= FP[-4]), and save the FP value at FP[-12]. + * + * If the FRAME_POINTER is disabled, we have to use arm unwinder to find where + * the LR is stored. + */ +int notrace arch_rethook_prepare(struct rethook_node *rh, struct pt_regs *regs, bool mcount) +{ + unsigned long *lr_addr; + int ret; + + if (mcount) { + /* Clang + mcount case is not supported yet. */ + if (IS_ENABLED(CONFIG_CC_IS_CLANG)) + return -EOPNOTSUPP; + if (IS_ENABLED(CONFIG_FRAME_POINTER)) { + lr_addr = (unsigned long *)(regs->ARM_fp - 4); + rh->frame = *(unsigned long *)(regs->ARM_fp - 12); + } else { + struct stackframe frame; + + arm_get_current_stackframe(regs, &frame); + ret = unwind_frame(&frame); + if (ret < 0) + return -EINVAL; + + if (frame.lr_addr) + lr_addr = frame.lr_addr; + else + lr_addr = ®s->ARM_lr; + rh->frame = regs->ARM_fp; + } + } else { + lr_addr = ®s->ARM_lr; + rh->frame = regs->ARM_fp; + } + + /* Replace the return addr with trampoline addr. */ + rh->ret_addr = *lr_addr; + *lr_addr = (unsigned long)arch_rethook_trampoline; + + return 0; +} +NOKPROBE_SYMBOL(arch_rethook_prepare); From patchwork Fri Apr 8 00:51:24 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 12805982 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9AFF0C433F5 for ; Fri, 8 Apr 2022 00:53:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=QU4PLlokCfAgddukB9kKsSwSQx0oxHcRTh2FENoh37M=; b=aXQhE3aFVlASN9 lm2qsu4Wbbdq+YZpwR50A+ULqo+eOfKLxOhbV0zSmNsUlU03ZlacnzIxLuANscZM6kPHicOfMweV8 Kg8zxGAw4hVOdpVUnwc6jCmTX6EU7NIErsgJ5lznVQt4RK5zDobLJ9UhOQzKDFmIVUOYLEbymBvuc ND6ZmgAeKKs5xTshRXWWX86CxCH1qAeMWB9MO7R0yJtyPQcCTiIJJdNxiqpIQAVzZ0RjoSgzgzCt8 UFKSUO66dEWRkuAKeUqubYDR2s5LkYfyJ1pW4Q5YYbcB7WVUV40Fmk4B131Tu9Ih5Siq8TGtMVsk7 tKl5Etv5RmJ43Q3ckFRA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nccqm-00ETGf-Hq; Fri, 08 Apr 2022 00:51:44 +0000 Received: from sin.source.kernel.org ([145.40.73.55]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nccqf-00ETDS-AD for linux-arm-kernel@lists.infradead.org; Fri, 08 Apr 2022 00:51:39 +0000 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 sin.source.kernel.org (Postfix) with ESMTPS id 62795CE29E4; Fri, 8 Apr 2022 00:51:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 944B8C385A0; Fri, 8 Apr 2022 00:51:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1649379090; bh=KTViDMcxBzExioMg7uvqJuqnGhuIn8+lCJ3XO40ZGTg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=o7MycGJCN5GKZNZM2h+DdH5PpGL2HnPeiUJnResL3fv3UX+RLsPhlfqDXT159QvcB RthDzy/AlK8V7I6v3cbQ1tiwpfsMpO2sd4t+Gvhi/ZUlI1z5JORBI1WrxiDDs1G0UG Uan5fQBCxcRjl3/x7Kq9xBoHjhISWCdh+t+uM3bsvJR/rm4GvfATg0GKDccF0f09K9 AvrD86sfO74OoeDbsKwOODgmsI9lOPMSYghxorc1eNpJwXTi4fopusOfLiNj03zNoy WUcgw1u8IyQlZvLDELH04zemFKP2L4X1twmIJezYYuDkJoItOvb98SGinIXTKk4J2o krZflv5xcMr0w== From: Masami Hiramatsu To: Alexei Starovoitov , Alexei Starovoitov Cc: Daniel Borkmann , Shubham Bansal , Andrii Nakryiko , Masami Hiramatsu , bpf@vger.kernel.org, kernel-team@fb.com, Jiri Olsa , Steven Rostedt , "Naveen N . Rao" , Anil S Keshavamurthy , "David S . Miller" , linux-kernel@vger.kernel.org, Mark Rutland , Will Deacon , Ard Biesheuvel , Russell King , Catalin Marinas , linux-arm-kernel@lists.infradead.org Subject: [PATCH bpf v2 4/4] arm64: rethook: Replace kretprobe trampoline with rethook Date: Fri, 8 Apr 2022 09:51:24 +0900 Message-Id: <164937908437.1272679.6436265245953600367.stgit@devnote2> X-Mailer: git-send-email 2.25.1 In-Reply-To: <164937903547.1272679.7244379141135199176.stgit@devnote2> References: <164937903547.1272679.7244379141135199176.stgit@devnote2> User-Agent: StGit/0.19 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220407_175137_753662_8BF4BA26 X-CRM114-Status: GOOD ( 25.26 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Replace the kretprobe's trampoline code with the rethook on arm64. The rethook on arm64 is almost renamed from kretprobe trampoline code. The mechanism is completely same. Signed-off-by: Masami Hiramatsu --- Changes in v2: - Fix a compile warning about no prototype. --- arch/arm64/Kconfig | 1 arch/arm64/include/asm/kprobes.h | 2 - arch/arm64/include/asm/stacktrace.h | 2 - arch/arm64/kernel/Makefile | 1 arch/arm64/kernel/probes/Makefile | 1 arch/arm64/kernel/probes/kprobes.c | 15 ---- arch/arm64/kernel/probes/kprobes_trampoline.S | 86 ------------------------- arch/arm64/kernel/rethook.c | 28 ++++++++ arch/arm64/kernel/rethook_trampoline.S | 87 +++++++++++++++++++++++++ arch/arm64/kernel/stacktrace.c | 9 +-- 10 files changed, 123 insertions(+), 109 deletions(-) delete mode 100644 arch/arm64/kernel/probes/kprobes_trampoline.S create mode 100644 arch/arm64/kernel/rethook.c create mode 100644 arch/arm64/kernel/rethook_trampoline.S diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 57c4c995965f..7d2945930283 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -204,6 +204,7 @@ config ARM64 select HAVE_SYSCALL_TRACEPOINTS select HAVE_KPROBES select HAVE_KRETPROBES + select HAVE_RETHOOK select HAVE_GENERIC_VDSO select IOMMU_DMA if IOMMU_SUPPORT select IRQ_DOMAIN diff --git a/arch/arm64/include/asm/kprobes.h b/arch/arm64/include/asm/kprobes.h index 05cd82eeca13..4ac558058377 100644 --- a/arch/arm64/include/asm/kprobes.h +++ b/arch/arm64/include/asm/kprobes.h @@ -39,8 +39,6 @@ void arch_remove_kprobe(struct kprobe *); int kprobe_fault_handler(struct pt_regs *regs, unsigned int fsr); int kprobe_exceptions_notify(struct notifier_block *self, unsigned long val, void *data); -void __kretprobe_trampoline(void); -void __kprobes *trampoline_probe_handler(struct pt_regs *regs); #endif /* CONFIG_KPROBES */ #endif /* _ARM_KPROBES_H */ diff --git a/arch/arm64/include/asm/stacktrace.h b/arch/arm64/include/asm/stacktrace.h index e77cdef9ca29..f781874f1609 100644 --- a/arch/arm64/include/asm/stacktrace.h +++ b/arch/arm64/include/asm/stacktrace.h @@ -58,7 +58,7 @@ struct stackframe { DECLARE_BITMAP(stacks_done, __NR_STACK_TYPES); unsigned long prev_fp; enum stack_type prev_type; -#ifdef CONFIG_KRETPROBES +#if defined(CONFIG_RETHOOK) struct llist_node *kr_cur; #endif }; diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index 986837d7ec82..62e033b1b095 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -60,6 +60,7 @@ obj-$(CONFIG_ACPI_NUMA) += acpi_numa.o obj-$(CONFIG_ARM64_ACPI_PARKING_PROTOCOL) += acpi_parking_protocol.o obj-$(CONFIG_PARAVIRT) += paravirt.o obj-$(CONFIG_RANDOMIZE_BASE) += kaslr.o +obj-$(CONFIG_RETHOOK) += rethook.o rethook_trampoline.o obj-$(CONFIG_HIBERNATION) += hibernate.o hibernate-asm.o obj-$(CONFIG_ELF_CORE) += elfcore.o obj-$(CONFIG_KEXEC_CORE) += machine_kexec.o relocate_kernel.o \ diff --git a/arch/arm64/kernel/probes/Makefile b/arch/arm64/kernel/probes/Makefile index 8e4be92e25b1..1fa58cda64ff 100644 --- a/arch/arm64/kernel/probes/Makefile +++ b/arch/arm64/kernel/probes/Makefile @@ -1,6 +1,5 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_KPROBES) += kprobes.o decode-insn.o \ - kprobes_trampoline.o \ simulate-insn.o obj-$(CONFIG_UPROBES) += uprobes.o decode-insn.o \ simulate-insn.o diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c index d9dfa82c1f18..4a3cc266e77e 100644 --- a/arch/arm64/kernel/probes/kprobes.c +++ b/arch/arm64/kernel/probes/kprobes.c @@ -399,21 +399,6 @@ int __init arch_populate_kprobe_blacklist(void) return ret; } -void __kprobes __used *trampoline_probe_handler(struct pt_regs *regs) -{ - return (void *)kretprobe_trampoline_handler(regs, (void *)regs->regs[29]); -} - -void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, - struct pt_regs *regs) -{ - ri->ret_addr = (kprobe_opcode_t *)regs->regs[30]; - ri->fp = (void *)regs->regs[29]; - - /* replace return addr (x30) with trampoline */ - regs->regs[30] = (long)&__kretprobe_trampoline; -} - int __kprobes arch_trampoline_kprobe(struct kprobe *p) { return 0; diff --git a/arch/arm64/kernel/probes/kprobes_trampoline.S b/arch/arm64/kernel/probes/kprobes_trampoline.S deleted file mode 100644 index 9a6499bed58b..000000000000 --- a/arch/arm64/kernel/probes/kprobes_trampoline.S +++ /dev/null @@ -1,86 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -/* - * trampoline entry and return code for kretprobes. - */ - -#include -#include -#include - - .text - - .macro save_all_base_regs - stp x0, x1, [sp, #S_X0] - stp x2, x3, [sp, #S_X2] - stp x4, x5, [sp, #S_X4] - stp x6, x7, [sp, #S_X6] - stp x8, x9, [sp, #S_X8] - stp x10, x11, [sp, #S_X10] - stp x12, x13, [sp, #S_X12] - stp x14, x15, [sp, #S_X14] - stp x16, x17, [sp, #S_X16] - stp x18, x19, [sp, #S_X18] - stp x20, x21, [sp, #S_X20] - stp x22, x23, [sp, #S_X22] - stp x24, x25, [sp, #S_X24] - stp x26, x27, [sp, #S_X26] - stp x28, x29, [sp, #S_X28] - add x0, sp, #PT_REGS_SIZE - stp lr, x0, [sp, #S_LR] - /* - * Construct a useful saved PSTATE - */ - mrs x0, nzcv - mrs x1, daif - orr x0, x0, x1 - mrs x1, CurrentEL - orr x0, x0, x1 - mrs x1, SPSel - orr x0, x0, x1 - stp xzr, x0, [sp, #S_PC] - .endm - - .macro restore_all_base_regs - ldr x0, [sp, #S_PSTATE] - and x0, x0, #(PSR_N_BIT | PSR_Z_BIT | PSR_C_BIT | PSR_V_BIT) - msr nzcv, x0 - ldp x0, x1, [sp, #S_X0] - ldp x2, x3, [sp, #S_X2] - ldp x4, x5, [sp, #S_X4] - ldp x6, x7, [sp, #S_X6] - ldp x8, x9, [sp, #S_X8] - ldp x10, x11, [sp, #S_X10] - ldp x12, x13, [sp, #S_X12] - ldp x14, x15, [sp, #S_X14] - ldp x16, x17, [sp, #S_X16] - ldp x18, x19, [sp, #S_X18] - ldp x20, x21, [sp, #S_X20] - ldp x22, x23, [sp, #S_X22] - ldp x24, x25, [sp, #S_X24] - ldp x26, x27, [sp, #S_X26] - ldp x28, x29, [sp, #S_X28] - .endm - -SYM_CODE_START(__kretprobe_trampoline) - sub sp, sp, #PT_REGS_SIZE - - save_all_base_regs - - /* Setup a frame pointer. */ - add x29, sp, #S_FP - - mov x0, sp - bl trampoline_probe_handler - /* - * Replace trampoline address in lr with actual orig_ret_addr return - * address. - */ - mov lr, x0 - - /* The frame pointer (x29) is restored with other registers. */ - restore_all_base_regs - - add sp, sp, #PT_REGS_SIZE - ret - -SYM_CODE_END(__kretprobe_trampoline) diff --git a/arch/arm64/kernel/rethook.c b/arch/arm64/kernel/rethook.c new file mode 100644 index 000000000000..07d8f6ea34a0 --- /dev/null +++ b/arch/arm64/kernel/rethook.c @@ -0,0 +1,28 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Generic return hook for arm64. + * Most of the code is copied from arch/arm64/kernel/probes/kprobes.c + */ + +#include +#include + +/* This is called from arch_rethook_trampoline() */ +unsigned long __used arch_rethook_trampoline_callback(struct pt_regs *regs); + +unsigned long __used arch_rethook_trampoline_callback(struct pt_regs *regs) +{ + return rethook_trampoline_handler(regs, regs->regs[29]); +} +NOKPROBE_SYMBOL(arch_rethook_trampoline_callback); + +int arch_rethook_prepare(struct rethook_node *rhn, struct pt_regs *regs, bool mcount) +{ + rhn->ret_addr = regs->regs[30]; + rhn->frame = regs->regs[29]; + + /* replace return addr (x30) with trampoline */ + regs->regs[30] = (u64)arch_rethook_trampoline; + return 0; +} +NOKPROBE_SYMBOL(arch_rethook_prepare); diff --git a/arch/arm64/kernel/rethook_trampoline.S b/arch/arm64/kernel/rethook_trampoline.S new file mode 100644 index 000000000000..146d4553674c --- /dev/null +++ b/arch/arm64/kernel/rethook_trampoline.S @@ -0,0 +1,87 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * trampoline entry and return code for rethook. + * Renamed from arch/arm64/kernel/probes/kprobes_trampoline.S + */ + +#include +#include +#include + + .text + + .macro save_all_base_regs + stp x0, x1, [sp, #S_X0] + stp x2, x3, [sp, #S_X2] + stp x4, x5, [sp, #S_X4] + stp x6, x7, [sp, #S_X6] + stp x8, x9, [sp, #S_X8] + stp x10, x11, [sp, #S_X10] + stp x12, x13, [sp, #S_X12] + stp x14, x15, [sp, #S_X14] + stp x16, x17, [sp, #S_X16] + stp x18, x19, [sp, #S_X18] + stp x20, x21, [sp, #S_X20] + stp x22, x23, [sp, #S_X22] + stp x24, x25, [sp, #S_X24] + stp x26, x27, [sp, #S_X26] + stp x28, x29, [sp, #S_X28] + add x0, sp, #PT_REGS_SIZE + stp lr, x0, [sp, #S_LR] + /* + * Construct a useful saved PSTATE + */ + mrs x0, nzcv + mrs x1, daif + orr x0, x0, x1 + mrs x1, CurrentEL + orr x0, x0, x1 + mrs x1, SPSel + orr x0, x0, x1 + stp xzr, x0, [sp, #S_PC] + .endm + + .macro restore_all_base_regs + ldr x0, [sp, #S_PSTATE] + and x0, x0, #(PSR_N_BIT | PSR_Z_BIT | PSR_C_BIT | PSR_V_BIT) + msr nzcv, x0 + ldp x0, x1, [sp, #S_X0] + ldp x2, x3, [sp, #S_X2] + ldp x4, x5, [sp, #S_X4] + ldp x6, x7, [sp, #S_X6] + ldp x8, x9, [sp, #S_X8] + ldp x10, x11, [sp, #S_X10] + ldp x12, x13, [sp, #S_X12] + ldp x14, x15, [sp, #S_X14] + ldp x16, x17, [sp, #S_X16] + ldp x18, x19, [sp, #S_X18] + ldp x20, x21, [sp, #S_X20] + ldp x22, x23, [sp, #S_X22] + ldp x24, x25, [sp, #S_X24] + ldp x26, x27, [sp, #S_X26] + ldp x28, x29, [sp, #S_X28] + .endm + +SYM_CODE_START(arch_rethook_trampoline) + sub sp, sp, #PT_REGS_SIZE + + save_all_base_regs + + /* Setup a frame pointer. */ + add x29, sp, #S_FP + + mov x0, sp + bl arch_rethook_trampoline_callback + /* + * Replace trampoline address in lr with actual orig_ret_addr return + * address. + */ + mov lr, x0 + + /* The frame pointer (x29) is restored with other registers. */ + restore_all_base_regs + + add sp, sp, #PT_REGS_SIZE + ret + +SYM_CODE_END(arch_rethook_trampoline) diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c index e4103e085681..5b717af4b555 100644 --- a/arch/arm64/kernel/stacktrace.c +++ b/arch/arm64/kernel/stacktrace.c @@ -8,6 +8,7 @@ #include #include #include +#include #include #include #include @@ -38,7 +39,7 @@ static notrace void start_backtrace(struct stackframe *frame, unsigned long fp, { frame->fp = fp; frame->pc = pc; -#ifdef CONFIG_KRETPROBES +#if defined(CONFIG_RETHOOK) frame->kr_cur = NULL; #endif @@ -134,9 +135,9 @@ static int notrace unwind_frame(struct task_struct *tsk, frame->pc = orig_pc; } #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ -#ifdef CONFIG_KRETPROBES - if (is_kretprobe_trampoline(frame->pc)) - frame->pc = kretprobe_find_ret_addr(tsk, (void *)frame->fp, &frame->kr_cur); +#ifdef CONFIG_RETHOOK + if (is_rethook_trampoline(frame->pc)) + frame->pc = rethook_find_ret_addr(tsk, frame->fp, &frame->kr_cur); #endif return 0;