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 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 24E8ACDB465 for ; Mon, 16 Oct 2023 08:04:33 +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:Message-ID:In-Reply-To: Date:From:Cc:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:References: List-Owner; bh=YetkJ8euRPauCWuEpaFd7tGi1d2ThsUhyDzH6Im2Hts=; b=gmYXjC+1YhL4Xb K6gcpv06Vd3NPGFr97oBkL6ECnQm3LcepwG0+7SmqFbU1S50lX4HNVdlRaLsLUZYk2OPP+Stj8Qrn rdmDJakrB5cn1Q+8A/pktDkxC66Tmz5oJVqHGZZY3M+unXKowKzQ+umrjftn+26MG7nOtQ4iDJ/l1 aG4iQRf4ep3yTS+imxPkH7fRZr0tuxlacAcpMzBiDLSOGnLawoMmEwzFcGWE7PmbZKaQOTesHscZI QNqSo8QNRVYyZ1oSvdFco7ajvtBf8ehTJhCqRZIn5DAgLKXVyKZ12oJV1Z5lWlxXCVeSj2eT1iXFx BVv4gvYplJMS0fwT76KQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qsIa1-008l26-29; Mon, 16 Oct 2023 08:04:01 +0000 Received: from ams.source.kernel.org ([145.40.68.75]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qsIZW-008kgF-2T for linux-arm-kernel@lists.infradead.org; Mon, 16 Oct 2023 08:03:33 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by ams.source.kernel.org (Postfix) with ESMTP id 597B3B80D07; Mon, 16 Oct 2023 08:03:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 11221C433CC; Mon, 16 Oct 2023 08:03:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1697443408; bh=EsYv8IQcxHtRkufOYoR2W4nxtKeDhL5sxBHSzThZ3DM=; h=Subject:To:Cc:From:Date:In-Reply-To:From; b=F0pdRPfdxnMCiY1fGw3zUGN8abIH96El174/yWSz5pSENIvkeGJ/FzZelBJtsbsc8 o64V3oTlTPmM/04/WjvCstagLPsPf7nqALbuupfQPdFOeC6r7VW102HED6vPZElRQJ 3LiKWzASh9wcV8nehGZ6Oa2D/w/SWVBwIhp4MN0A= Subject: Patch "arm64: rework FPAC exception handling" has been added to the 5.10-stable tree To: alexandru.elisei@arm.com,amit.kachhap@arm.com,anshuman.khandual@arm.com,ardb@kernel.org,broonie@kernel.org,catalin.marinas@arm.com,ebiederm@xmission.com,f.fainelli@gmail.com,gregkh@linuxfoundation.org,haibinzhang@tencent.com,hewenliang4@huawei.com,james.morse@arm.com,linux-arm-kernel@lists.infradead.org,mark.rutland@arm.com,ruanjinjie@huawei.com,sashal@kernel.org,scott@os.amperecomputing.com,stable@kernel.org,will@kernel.org,youngmin.nam@samsung.com,yuzenghui@huawei.com Cc: From: Date: Mon, 16 Oct 2023 10:02:25 +0200 In-Reply-To: <20231011100545.979577-5-ruanjinjie@huawei.com> Message-ID: <2023101625-mortician-tarantula-72e3@gregkh> MIME-Version: 1.0 X-stable: commit X-Patchwork-Hint: ignore X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231016_010331_160912_84D1E372 X-CRM114-Status: GOOD ( 18.31 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org This is a note to let you know that I've just added the patch titled arm64: rework FPAC exception handling to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: arm64-rework-fpac-exception-handling.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >From ruanjinjie@huawei.com Wed Oct 11 12:06:31 2023 From: Jinjie Ruan Date: Wed, 11 Oct 2023 10:05:34 +0000 Subject: arm64: rework FPAC exception handling To: , , , , , , , , , , , , , , , , , , Cc: Message-ID: <20231011100545.979577-5-ruanjinjie@huawei.com> From: Mark Rutland commit a1fafa3b24a70461bbf3e5c0770893feb0a49292 upstream. If an FPAC exception is taken from EL1, the entry code will call do_ptrauth_fault(), where due to: BUG_ON(!user_mode(regs)) ... the kernel will report a problem within do_ptrauth_fault() rather than reporting the original context the FPAC exception was taken from. The pt_regs and ESR value reported will be from within do_ptrauth_fault() and the code dump will be for the BRK in BUG_ON(), which isn't sufficient to debug the cause of the original exception. This patch makes the reporting better by having separate EL0 and EL1 FPAC exception handlers, with the latter calling die() directly to report the original context the FPAC exception was taken from. Note that we only need to prevent kprobes of the EL1 FPAC handler, since the EL0 FPAC handler cannot be called recursively. For consistency with do_el0_svc*(), I've named the split functions do_el{0,1}_fpac() rather than do_el{0,1}_ptrauth_fault(). I've also clarified the comment to not imply there are casues other than FPAC exceptions. Prior to this patch FPAC exceptions are reported as: | kernel BUG at arch/arm64/kernel/traps.c:517! | Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP | Modules linked in: | CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.19.0-rc3-00130-g9c8a180a1cdf-dirty #12 | Hardware name: FVP Base RevC (DT) | pstate: 00400009 (nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) | pc : do_ptrauth_fault+0x3c/0x40 | lr : el1_fpac+0x34/0x54 | sp : ffff80000a3bbc80 | x29: ffff80000a3bbc80 x28: ffff0008001d8000 x27: 0000000000000000 | x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000 | x23: 0000000020400009 x22: ffff800008f70fa4 x21: ffff80000a3bbe00 | x20: 0000000072000000 x19: ffff80000a3bbcb0 x18: fffffbfffda37000 | x17: 3120676e696d7573 x16: 7361202c6e6f6974 x15: 0000000081a90000 | x14: 0040000000000041 x13: 0040000000000001 x12: ffff000001a90000 | x11: fffffbfffda37480 x10: 0068000000000703 x9 : 0001000080000000 | x8 : 0000000000090000 x7 : 0068000000000f03 x6 : 0060000000000783 | x5 : ffff80000a3bbcb0 x4 : ffff0008001d8000 x3 : 0000000072000000 | x2 : 0000000000000000 x1 : 0000000020400009 x0 : ffff80000a3bbcb0 | Call trace: | do_ptrauth_fault+0x3c/0x40 | el1h_64_sync_handler+0xc4/0xd0 | el1h_64_sync+0x64/0x68 | test_pac+0x8/0x10 | smp_init+0x7c/0x8c | kernel_init_freeable+0x128/0x28c | kernel_init+0x28/0x13c | ret_from_fork+0x10/0x20 | Code: 97fffe5e a8c17bfd d50323bf d65f03c0 (d4210000) With this patch applied FPAC exceptions are reported as: | Internal error: Oops - FPAC: 0000000072000000 [#1] PREEMPT SMP | Modules linked in: | CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.19.0-rc3-00132-g78846e1c4757-dirty #11 | Hardware name: FVP Base RevC (DT) | pstate: 20400009 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) | pc : test_pac+0x8/0x10 | lr : 0x0 | sp : ffff80000a3bbe00 | x29: ffff80000a3bbe00 x28: 0000000000000000 x27: 0000000000000000 | x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000 | x23: ffff80000a2c8000 x22: 0000000000000000 x21: 0000000000000000 | x20: ffff8000099fa5b0 x19: ffff80000a007000 x18: fffffbfffda37000 | x17: 3120676e696d7573 x16: 7361202c6e6f6974 x15: 0000000081a90000 | x14: 0040000000000041 x13: 0040000000000001 x12: ffff000001a90000 | x11: fffffbfffda37480 x10: 0068000000000703 x9 : 0001000080000000 | x8 : 0000000000090000 x7 : 0068000000000f03 x6 : 0060000000000783 | x5 : ffff80000a2c6000 x4 : ffff0008001d8000 x3 : ffff800009f88378 | x2 : 0000000000000000 x1 : 0000000080210000 x0 : ffff000001a90000 | Call trace: | test_pac+0x8/0x10 | smp_init+0x7c/0x8c | kernel_init_freeable+0x128/0x28c | kernel_init+0x28/0x13c | ret_from_fork+0x10/0x20 | Code: d50323bf d65f03c0 d503233f aa1f03fe (d50323bf) Signed-off-by: Mark Rutland Reviewed-by: Mark Brown Reviewed-by: Anshuman Khandual Cc: Alexandru Elisei Cc: Amit Daniel Kachhap Cc: James Morse Cc: Will Deacon Link: https://lore.kernel.org/r/20220913101732.3925290-5-mark.rutland@arm.com Signed-off-by: Catalin Marinas Signed-off-by: Jinjie Ruan Signed-off-by: Greg Kroah-Hartman --- arch/arm64/include/asm/exception.h | 3 ++- arch/arm64/kernel/entry-common.c | 4 ++-- arch/arm64/kernel/traps.c | 16 ++++++++++------ 3 files changed, 14 insertions(+), 9 deletions(-) --- a/arch/arm64/include/asm/exception.h +++ b/arch/arm64/include/asm/exception.h @@ -47,5 +47,6 @@ void bad_el0_sync(struct pt_regs *regs, void do_cp15instr(unsigned int esr, struct pt_regs *regs); void do_el0_svc(struct pt_regs *regs); void do_el0_svc_compat(struct pt_regs *regs); -void do_ptrauth_fault(struct pt_regs *regs, unsigned int esr); +void do_el0_fpac(struct pt_regs *regs, unsigned long esr); +void do_el1_fpac(struct pt_regs *regs, unsigned long esr); #endif /* __ASM_EXCEPTION_H */ --- a/arch/arm64/kernel/entry-common.c +++ b/arch/arm64/kernel/entry-common.c @@ -187,7 +187,7 @@ static void noinstr el1_fpac(struct pt_r { enter_from_kernel_mode(regs); local_daif_inherit(regs); - do_ptrauth_fault(regs, esr); + do_el1_fpac(regs, esr); local_daif_mask(); exit_to_kernel_mode(regs); } @@ -357,7 +357,7 @@ static void noinstr el0_fpac(struct pt_r { enter_from_user_mode(); local_daif_restore(DAIF_PROCCTX); - do_ptrauth_fault(regs, esr); + do_el0_fpac(regs, esr); } asmlinkage void noinstr el0_sync_handler(struct pt_regs *regs) --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -418,16 +418,20 @@ void do_bti(struct pt_regs *regs) } NOKPROBE_SYMBOL(do_bti); -void do_ptrauth_fault(struct pt_regs *regs, unsigned int esr) +void do_el0_fpac(struct pt_regs *regs, unsigned long esr) +{ + force_signal_inject(SIGILL, ILL_ILLOPN, regs->pc, esr); +} + +void do_el1_fpac(struct pt_regs *regs, unsigned long esr) { /* - * Unexpected FPAC exception or pointer authentication failure in - * the kernel: kill the task before it does any more harm. + * Unexpected FPAC exception in the kernel: kill the task before it + * does any more harm. */ - BUG_ON(!user_mode(regs)); - force_signal_inject(SIGILL, ILL_ILLOPN, regs->pc, esr); + die("Oops - FPAC", regs, esr); } -NOKPROBE_SYMBOL(do_ptrauth_fault); +NOKPROBE_SYMBOL(do_el1_fpac); #define __user_cache_maint(insn, address, res) \ if (address >= user_addr_max()) { \ Patches currently in stable-queue which might be from ruanjinjie@huawei.com are queue-5.10/arm64-factor-insn-read-out-of-call_undef_hook.patch queue-5.10/arm64-rework-el0-mrs-emulation.patch queue-5.10/arm64-die-pass-err-as-long.patch queue-5.10/arm64-armv8_deprecated-rework-deprected-instruction-handling.patch queue-5.10/arm64-armv8_deprecated-fix-unused-function-error.patch queue-5.10/arm64-armv8_deprecated-move-aarch32-helper-earlier.patch queue-5.10/arm64-consistently-pass-esr_elx-to-die.patch queue-5.10/arm64-factor-out-el1-ssbs-emulation-hook.patch queue-5.10/arm64-report-el1-undefs-better.patch queue-5.10/arm64-armv8_deprecated-fold-ops-into-insn_emulation.patch queue-5.10/arm64-rework-bti-exception-handling.patch queue-5.10/arm64-rework-fpac-exception-handling.patch queue-5.10/arm64-split-el0-el1-undef-handlers.patch queue-5.10/arm64-allow-kprobes-on-el0-handlers.patch queue-5.10/arm64-armv8_deprecated-move-emulation-functions.patch _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel