From patchwork Fri Mar 12 06:42:17 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 12133789 X-Patchwork-Delegate: bpf@iogearbox.net 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=-19.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 183FDC433E0 for ; Fri, 12 Mar 2021 06:42:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DC20A64F93 for ; Fri, 12 Mar 2021 06:42:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232066AbhCLGm0 (ORCPT ); Fri, 12 Mar 2021 01:42:26 -0500 Received: from mail.kernel.org ([198.145.29.99]:44152 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232057AbhCLGmX (ORCPT ); Fri, 12 Mar 2021 01:42:23 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id C79F064F80; Fri, 12 Mar 2021 06:42:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1615531342; bh=cTsmuevKLqMC2k5muPF+Y0tyeM9LMo6Uyt3vhXYxtyk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RYq0fEwAX1fHd+QC5qQV+Neh/HXmrLRI7sJlOsDPcM0ChwcWN/rYNpPle3k5k+XYd O80G9dLG6WCltXTWn2A+Oa1tN/p7Q9a22nWoU0q0oQ720ePI7ot9Dwc3RuufhZpF+1 YPOkV1cI10CyFAmHXRiTj7LT/5k36GKmrcBC6bVeRj+0eei+ZIyGThYr3FlkPwFRFl 0rYj/NmgMiGkUaPqiYIaEi6rIXdaWnS8hSFVjpIKxN3ICZ5Xb8qmgKbbEVf9RaNjPF TuuV7YW7kMNw/zoq2z4PrFmY0De5u7LPhL6yErKOmpyOVpblDnmsCTC2bBvaOcJPtD FDDUg9LXiP4vw== From: Masami Hiramatsu To: Steven Rostedt , Ingo Molnar Cc: X86 ML , Masami Hiramatsu , Daniel Xu , linux-kernel@vger.kernel.org, bpf@vger.kernel.org, kuba@kernel.org, mingo@redhat.com, ast@kernel.org, tglx@linutronix.de, kernel-team@fb.com, yhs@fb.com, Josh Poimboeuf Subject: [PATCH -tip v2 03/10] kprobes: treewide: Remove trampoline_address from kretprobe_trampoline_handler() Date: Fri, 12 Mar 2021 15:42:17 +0900 Message-Id: <161553133723.1038734.12733900684358597420.stgit@devnote2> X-Mailer: git-send-email 2.25.1 In-Reply-To: <161553130371.1038734.7661319550287837734.stgit@devnote2> References: <161553130371.1038734.7661319550287837734.stgit@devnote2> User-Agent: StGit/0.19 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Remove trampoline_address from kretprobe_trampoline_handler(). Instead of passing the address, kretprobe_trampoline_handler() can use new kretprobe_trampoline_addr(). Signed-off-by: Masami Hiramatsu --- Changes in v2: - Remove arch_deref_entry_point() from comment. --- arch/arc/kernel/kprobes.c | 2 +- arch/arm/probes/kprobes/core.c | 3 +-- arch/arm64/kernel/probes/kprobes.c | 3 +-- arch/csky/kernel/probes/kprobes.c | 2 +- arch/ia64/kernel/kprobes.c | 5 ++--- arch/mips/kernel/kprobes.c | 3 +-- arch/parisc/kernel/kprobes.c | 4 ++-- arch/powerpc/kernel/kprobes.c | 2 +- arch/riscv/kernel/probes/kprobes.c | 2 +- arch/s390/kernel/kprobes.c | 2 +- arch/sh/kernel/kprobes.c | 2 +- arch/sparc/kernel/kprobes.c | 2 +- arch/x86/kernel/kprobes/core.c | 2 +- include/linux/kprobes.h | 18 +++++++++++++----- kernel/kprobes.c | 3 +-- 15 files changed, 29 insertions(+), 26 deletions(-) diff --git a/arch/arc/kernel/kprobes.c b/arch/arc/kernel/kprobes.c index cabef45f11df..3ae01bb5820c 100644 --- a/arch/arc/kernel/kprobes.c +++ b/arch/arc/kernel/kprobes.c @@ -397,7 +397,7 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, static int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) { - regs->ret = __kretprobe_trampoline_handler(regs, &kretprobe_trampoline, NULL); + regs->ret = __kretprobe_trampoline_handler(regs, NULL); /* By returning a non zero value, we are telling the kprobe handler * that we don't want the post_handler to run diff --git a/arch/arm/probes/kprobes/core.c b/arch/arm/probes/kprobes/core.c index a9653117ca0d..1782b41df095 100644 --- a/arch/arm/probes/kprobes/core.c +++ b/arch/arm/probes/kprobes/core.c @@ -413,8 +413,7 @@ void __naked __kprobes kretprobe_trampoline(void) /* Called from kretprobe_trampoline */ static __used __kprobes void *trampoline_handler(struct pt_regs *regs) { - return (void *)kretprobe_trampoline_handler(regs, &kretprobe_trampoline, - (void *)regs->ARM_fp); + return (void *)kretprobe_trampoline_handler(regs, (void *)regs->ARM_fp); } void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c index 66aac2881ba8..fce681fdfce6 100644 --- a/arch/arm64/kernel/probes/kprobes.c +++ b/arch/arm64/kernel/probes/kprobes.c @@ -412,8 +412,7 @@ int __init arch_populate_kprobe_blacklist(void) void __kprobes __used *trampoline_probe_handler(struct pt_regs *regs) { - return (void *)kretprobe_trampoline_handler(regs, &kretprobe_trampoline, - (void *)kernel_stack_pointer(regs)); + return (void *)kretprobe_trampoline_handler(regs, (void *)kernel_stack_pointer(regs)); } void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, diff --git a/arch/csky/kernel/probes/kprobes.c b/arch/csky/kernel/probes/kprobes.c index 589f090f48b9..cc589bc11904 100644 --- a/arch/csky/kernel/probes/kprobes.c +++ b/arch/csky/kernel/probes/kprobes.c @@ -404,7 +404,7 @@ int __init arch_populate_kprobe_blacklist(void) void __kprobes __used *trampoline_probe_handler(struct pt_regs *regs) { - return (void *)kretprobe_trampoline_handler(regs, &kretprobe_trampoline, NULL); + return (void *)kretprobe_trampoline_handler(regs, NULL); } void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, diff --git a/arch/ia64/kernel/kprobes.c b/arch/ia64/kernel/kprobes.c index 15871eb170c0..a008df8e7203 100644 --- a/arch/ia64/kernel/kprobes.c +++ b/arch/ia64/kernel/kprobes.c @@ -392,14 +392,13 @@ static void __kprobes set_current_kprobe(struct kprobe *p, __this_cpu_write(current_kprobe, p); } -static void kretprobe_trampoline(void) +void kretprobe_trampoline(void) { } int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) { - regs->cr_iip = __kretprobe_trampoline_handler(regs, - dereference_function_descriptor(kretprobe_trampoline), NULL); + regs->cr_iip = __kretprobe_trampoline_handler(regs, NULL); /* * By returning a non-zero value, we are telling * kprobe_handler() that we don't want the post_handler diff --git a/arch/mips/kernel/kprobes.c b/arch/mips/kernel/kprobes.c index 54dfba8fa77c..001a2f07ef44 100644 --- a/arch/mips/kernel/kprobes.c +++ b/arch/mips/kernel/kprobes.c @@ -489,8 +489,7 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, static int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) { - instruction_pointer(regs) = __kretprobe_trampoline_handler(regs, - kretprobe_trampoline, NULL); + instruction_pointer(regs) = __kretprobe_trampoline_handler(regs, NULL); /* * By returning a non-zero value, we are telling * kprobe_handler() that we don't want the post_handler diff --git a/arch/parisc/kernel/kprobes.c b/arch/parisc/kernel/kprobes.c index 6d21a515eea5..4a35ac6e2ca2 100644 --- a/arch/parisc/kernel/kprobes.c +++ b/arch/parisc/kernel/kprobes.c @@ -175,7 +175,7 @@ int __kprobes parisc_kprobe_ss_handler(struct pt_regs *regs) return 1; } -static inline void kretprobe_trampoline(void) +void kretprobe_trampoline(void) { asm volatile("nop"); asm volatile("nop"); @@ -193,7 +193,7 @@ static int __kprobes trampoline_probe_handler(struct kprobe *p, { unsigned long orig_ret_address; - orig_ret_address = __kretprobe_trampoline_handler(regs, trampoline_p.addr, NULL); + orig_ret_address = __kretprobe_trampoline_handler(regs, NULL); instruction_pointer_set(regs, orig_ret_address); return 1; diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c index eb0460949e1b..dfd532c43525 100644 --- a/arch/powerpc/kernel/kprobes.c +++ b/arch/powerpc/kernel/kprobes.c @@ -399,7 +399,7 @@ static int trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) { unsigned long orig_ret_address; - orig_ret_address = __kretprobe_trampoline_handler(regs, &kretprobe_trampoline, NULL); + orig_ret_address = __kretprobe_trampoline_handler(regs, NULL); /* * We get here through one of two paths: * 1. by taking a trap -> kprobe_handler() -> here diff --git a/arch/riscv/kernel/probes/kprobes.c b/arch/riscv/kernel/probes/kprobes.c index a2ec18662fee..619339f1d3ba 100644 --- a/arch/riscv/kernel/probes/kprobes.c +++ b/arch/riscv/kernel/probes/kprobes.c @@ -376,7 +376,7 @@ int __init arch_populate_kprobe_blacklist(void) void __kprobes __used *trampoline_probe_handler(struct pt_regs *regs) { - return (void *)kretprobe_trampoline_handler(regs, &kretprobe_trampoline, NULL); + return (void *)kretprobe_trampoline_handler(regs, NULL); } void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, diff --git a/arch/s390/kernel/kprobes.c b/arch/s390/kernel/kprobes.c index aae24dc75df6..b149e9169709 100644 --- a/arch/s390/kernel/kprobes.c +++ b/arch/s390/kernel/kprobes.c @@ -351,7 +351,7 @@ static void __used kretprobe_trampoline_holder(void) */ static int trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) { - regs->psw.addr = __kretprobe_trampoline_handler(regs, &kretprobe_trampoline, NULL); + regs->psw.addr = __kretprobe_trampoline_handler(regs, NULL); /* * By returning a non-zero value, we are telling * kprobe_handler() that we don't want the post_handler diff --git a/arch/sh/kernel/kprobes.c b/arch/sh/kernel/kprobes.c index 756100b01e84..48356e81836a 100644 --- a/arch/sh/kernel/kprobes.c +++ b/arch/sh/kernel/kprobes.c @@ -303,7 +303,7 @@ static void __used kretprobe_trampoline_holder(void) */ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) { - regs->pc = __kretprobe_trampoline_handler(regs, &kretprobe_trampoline, NULL); + regs->pc = __kretprobe_trampoline_handler(regs, NULL); return 1; } diff --git a/arch/sparc/kernel/kprobes.c b/arch/sparc/kernel/kprobes.c index 217c21a6986a..fa30f9dadff8 100644 --- a/arch/sparc/kernel/kprobes.c +++ b/arch/sparc/kernel/kprobes.c @@ -468,7 +468,7 @@ static int __kprobes trampoline_probe_handler(struct kprobe *p, { unsigned long orig_ret_address = 0; - orig_ret_address = __kretprobe_trampoline_handler(regs, &kretprobe_trampoline, NULL); + orig_ret_address = __kretprobe_trampoline_handler(regs, NULL); regs->tpc = orig_ret_address; regs->tnpc = orig_ret_address + 4; diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c index 1f58e89eeccd..3c00b773fe2e 100644 --- a/arch/x86/kernel/kprobes/core.c +++ b/arch/x86/kernel/kprobes/core.c @@ -1062,7 +1062,7 @@ __used __visible void *trampoline_handler(struct pt_regs *regs) regs->ip = (unsigned long)&kretprobe_trampoline; regs->orig_ax = ~0UL; - return (void *)kretprobe_trampoline_handler(regs, &kretprobe_trampoline, ®s->sp); + return (void *)kretprobe_trampoline_handler(regs, ®s->sp); } NOKPROBE_SYMBOL(trampoline_handler); diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h index d65c041b5c22..65dadd4238a2 100644 --- a/include/linux/kprobes.h +++ b/include/linux/kprobes.h @@ -205,15 +205,23 @@ extern void arch_prepare_kretprobe(struct kretprobe_instance *ri, struct pt_regs *regs); extern int arch_trampoline_kprobe(struct kprobe *p); +void kretprobe_trampoline(void); +/* + * Since some architecture uses structured function pointer, + * use dereference_function_descriptor() to get real function address. + */ +static nokprobe_inline void *kretprobe_trampoline_addr(void) +{ + return dereference_function_descriptor(kretprobe_trampoline); +} + /* If the trampoline handler called from a kprobe, use this version */ unsigned long __kretprobe_trampoline_handler(struct pt_regs *regs, - void *trampoline_address, - void *frame_pointer); + void *frame_pointer); static nokprobe_inline unsigned long kretprobe_trampoline_handler(struct pt_regs *regs, - void *trampoline_address, - void *frame_pointer) + void *frame_pointer) { unsigned long ret; /* @@ -222,7 +230,7 @@ unsigned long kretprobe_trampoline_handler(struct pt_regs *regs, * be running at this point. */ kprobe_busy_begin(); - ret = __kretprobe_trampoline_handler(regs, trampoline_address, frame_pointer); + ret = __kretprobe_trampoline_handler(regs, frame_pointer); kprobe_busy_end(); return ret; diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 2913de07f4a3..75c0a58c19c2 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1859,7 +1859,6 @@ static struct notifier_block kprobe_exceptions_nb = { #ifdef CONFIG_KRETPROBES unsigned long __kretprobe_trampoline_handler(struct pt_regs *regs, - void *trampoline_address, void *frame_pointer) { kprobe_opcode_t *correct_ret_addr = NULL; @@ -1874,7 +1873,7 @@ unsigned long __kretprobe_trampoline_handler(struct pt_regs *regs, BUG_ON(ri->fp != frame_pointer); - if (ri->ret_addr != trampoline_address) { + if (ri->ret_addr != kretprobe_trampoline_addr()) { correct_ret_addr = ri->ret_addr; /* * This is the real return address. Any other