linux-kernel - [PATCH v17 1/3] ACPI: APEI: send SIGBUS to current task if synchronous memory error not recovered

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20241202030527.20586-2-xueshuai@linux.alibaba.com>
Date: Mon,  2 Dec 2024 11:05:25 +0800
From: Shuai Xue <xueshuai@...ux.alibaba.com>
To: yazen.ghannam@....com,
	mark.rutland@....com,
	catalin.marinas@....com,
	mingo@...hat.com,
	robin.murphy@....com,
	Jonathan.Cameron@...wei.com,
	bp@...en8.de,
	rafael@...nel.org,
	linux-arm-kernel@...ts.infradead.org,
	wangkefeng.wang@...wei.com,
	tanxiaofei@...wei.com,
	mawupeng1@...wei.com,
	tony.luck@...el.com,
	linmiaohe@...wei.com,
	naoya.horiguchi@....com,
	james.morse@....com,
	tongtiangen@...wei.com,
	gregkh@...uxfoundation.org,
	will@...nel.org,
	jarkko@...nel.org
Cc: linux-acpi@...r.kernel.org,
	linux-mm@...ck.org,
	linux-kernel@...r.kernel.org,
	akpm@...ux-foundation.org,
	linux-edac@...r.kernel.org,
	x86@...nel.org,
	xueshuai@...ux.alibaba.com,
	justin.he@....com,
	ardb@...nel.org,
	ying.huang@...el.com,
	ashish.kalra@....com,
	baolin.wang@...ux.alibaba.com,
	tglx@...utronix.de,
	dave.hansen@...ux.intel.com,
	lenb@...nel.org,
	hpa@...or.com,
	robert.moore@...el.com,
	lvying6@...wei.com,
	xiexiuqi@...wei.com,
	zhuo.song@...ux.alibaba.com
Subject: [PATCH v17 1/3] ACPI: APEI: send SIGBUS to current task if synchronous memory error not recovered

Synchronous error was detected as a result of user-space process accessing
a 2-bit uncorrected error. The CPU will take a synchronous error exception
such as Synchronous External Abort (SEA) on Arm64. The kernel will queue a
memory_failure() work which poisons the related page, unmaps the page, and
then sends a SIGBUS to the process, so that a system wide panic can be
avoided.

However, no memory_failure() work will be queued when abnormal synchronous
errors occur. These errors can include situations such as invalid PA,
unexpected severity, no memory failure config support, invalid GUID
section, etc. In such case, the user-space process will trigger SEA again.
This loop can potentially exceed the platform firmware threshold or even
trigger a kernel hard lockup, leading to a system reboot.

Fix it by performing a force kill if no memory_failure() work is queued
for synchronous errors.

Signed-off-by: Shuai Xue <xueshuai@...ux.alibaba.com>
Reviewed-by: Jarkko Sakkinen <jarkko@...nel.org>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@...wei.com>
Reviewed-by: Yazen Ghannam <yazen.ghannam@....com>
---
 drivers/acpi/apei/ghes.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
index a2491905f165..106486bdfefc 100644
--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c
@@ -801,6 +801,17 @@ static bool ghes_do_proc(struct ghes *ghes,
 		}
 	}
 
+	/*
+	 * If no memory failure work is queued for abnormal synchronous
+	 * errors, do a force kill.
+	 */
+	if (sync && !queued) {
+		dev_err(ghes->dev,
+			HW_ERR GHES_PFX "%s:%d: synchronous unrecoverable error (SIGBUS)\n",
+			current->comm, task_pid_nr(current));
+		force_sig(SIGBUS);
+	}
+
 	return queued;
 }
 
-- 
2.39.3