From: Eric Biggers <ebiggers@kernel.org>
To: stable@vger.kernel.org
Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>,
Kees Cook <keescook@chromium.org>, SeongJae Park <sj@kernel.org>,
Seth Jenkins <sethjenkins@google.com>,
Jann Horn <jannh@google.com>,
"Eric W . Biederman" <ebiederm@xmission.com>,
linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org,
Petr Mladek <pmladek@suse.com>,
Andrew Morton <akpm@linux-foundation.org>,
tangmeng <tangmeng@uniontech.com>,
"Guilherme G. Piccoli" <gpiccoli@igalia.com>,
Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
Tiezhu Yang <yangtiezhu@loongson.cn>,
Luis Chamberlain <mcgrof@kernel.org>
Subject: [PATCH 4.14 14/16] panic: Expose "warn_count" to sysfs
Date: Wed, 1 Feb 2023 21:44:04 -0800 [thread overview]
Message-ID: <20230202054406.221721-15-ebiggers@kernel.org> (raw)
In-Reply-To: <20230202054406.221721-1-ebiggers@kernel.org>
From: Kees Cook <keescook@chromium.org>
commit 8b05aa26336113c4cea25f1c333ee8cd4fc212a6 upstream.
Since Warn count is now tracked and is a fairly interesting signal, add
the entry /sys/kernel/warn_count to expose it to userspace.
Cc: Petr Mladek <pmladek@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: tangmeng <tangmeng@uniontech.com>
Cc: "Guilherme G. Piccoli" <gpiccoli@igalia.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20221117234328.594699-6-keescook@chromium.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
.../ABI/testing/sysfs-kernel-warn_count | 6 +++++
kernel/panic.c | 22 +++++++++++++++++--
2 files changed, 26 insertions(+), 2 deletions(-)
create mode 100644 Documentation/ABI/testing/sysfs-kernel-warn_count
diff --git a/Documentation/ABI/testing/sysfs-kernel-warn_count b/Documentation/ABI/testing/sysfs-kernel-warn_count
new file mode 100644
index 0000000000000..08f083d2fd51b
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-kernel-warn_count
@@ -0,0 +1,6 @@
+What: /sys/kernel/oops_count
+Date: November 2022
+KernelVersion: 6.2.0
+Contact: Linux Kernel Hardening List <linux-hardening@vger.kernel.org>
+Description:
+ Shows how many times the system has Warned since last boot.
diff --git a/kernel/panic.c b/kernel/panic.c
index bfe6e4c5cd0e7..8f7bf0a8cef1a 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -28,6 +28,7 @@
#include <linux/console.h>
#include <linux/bug.h>
#include <linux/ratelimit.h>
+#include <linux/sysfs.h>
#define PANIC_TIMER_STEP 100
#define PANIC_BLINK_SPD 18
@@ -68,6 +69,25 @@ static __init int kernel_panic_sysctls_init(void)
late_initcall(kernel_panic_sysctls_init);
#endif
+static atomic_t warn_count = ATOMIC_INIT(0);
+
+#ifdef CONFIG_SYSFS
+static ssize_t warn_count_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *page)
+{
+ return sysfs_emit(page, "%d\n", atomic_read(&warn_count));
+}
+
+static struct kobj_attribute warn_count_attr = __ATTR_RO(warn_count);
+
+static __init int kernel_panic_sysfs_init(void)
+{
+ sysfs_add_file_to_group(kernel_kobj, &warn_count_attr.attr, NULL);
+ return 0;
+}
+late_initcall(kernel_panic_sysfs_init);
+#endif
+
static long no_blink(int state)
{
return 0;
@@ -145,8 +165,6 @@ EXPORT_SYMBOL(nmi_panic);
void check_panic_on_warn(const char *origin)
{
- static atomic_t warn_count = ATOMIC_INIT(0);
-
if (panic_on_warn)
panic("%s: panic_on_warn set ...\n", origin);
--
2.39.1
next prev parent reply other threads:[~2023-02-02 5:45 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-02-02 5:43 [PATCH 4.14 00/16] Backport oops_limit to 4.14 Eric Biggers
2023-02-02 5:43 ` [PATCH 4.14 01/16] sysctl: add a new register_sysctl_init() interface Eric Biggers
2023-02-02 5:43 ` [PATCH 4.14 02/16] panic: unset panic_on_warn inside panic() Eric Biggers
2023-02-02 5:43 ` [PATCH 4.14 03/16] mm: kasan: do not panic if both panic_on_warn and kasan_multishot set Eric Biggers
2023-02-02 5:43 ` [PATCH 4.14 04/16] exit: Add and use make_task_dead Eric Biggers
2023-02-02 5:43 ` [PATCH 4.14 05/16] objtool: Add a missing comma to avoid string concatenation Eric Biggers
2023-02-02 5:43 ` [PATCH 4.14 06/16] hexagon: Fix function name in die() Eric Biggers
2023-02-02 5:43 ` [PATCH 4.14 07/16] h8300: Fix build errors from do_exit() to make_task_dead() transition Eric Biggers
2023-02-02 5:43 ` [PATCH 4.14 08/16] ia64: make IA64_MCA_RECOVERY bool instead of tristate Eric Biggers
2023-02-02 5:43 ` [PATCH 4.14 09/16] exit: Put an upper limit on how often we can oops Eric Biggers
2023-02-02 5:44 ` [PATCH 4.14 10/16] exit: Expose "oops_count" to sysfs Eric Biggers
2023-02-02 5:44 ` [PATCH 4.14 11/16] exit: Allow oops_limit to be disabled Eric Biggers
2023-02-02 5:44 ` [PATCH 4.14 12/16] panic: Consolidate open-coded panic_on_warn checks Eric Biggers
2023-02-02 5:44 ` [PATCH 4.14 13/16] panic: Introduce warn_limit Eric Biggers
2023-02-02 5:44 ` Eric Biggers [this message]
2023-02-02 5:44 ` [PATCH 4.14 15/16] docs: Fix path paste-o for /sys/kernel/warn_count Eric Biggers
2023-02-02 5:44 ` [PATCH 4.14 16/16] exit: Use READ_ONCE() for all oops/warn limit reads Eric Biggers
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