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authorKees Cook <keescook@chromium.org>2023-01-24 11:30:01 -0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2023-02-01 08:23:21 +0100
commit8c99d4c4c192770e7ea622220e36f53b85152a75 (patch)
tree52d3d3dba7794aef987b69377e1ec54a17c08cfb /kernel
parent55eba18262cbc289ded9e7a8fe1b61a92140b59a (diff)
panic: Introduce warn_limit
commit 9fc9e278a5c0b708eeffaf47d6eb0c82aa74ed78 upstream. Like oops_limit, add warn_limit for limiting the number of warnings when panic_on_warn is not set. Cc: Jonathan Corbet <corbet@lwn.net> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: "Jason A. Donenfeld" <Jason@zx2c4.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Petr Mladek <pmladek@suse.com> Cc: tangmeng <tangmeng@uniontech.com> Cc: "Guilherme G. Piccoli" <gpiccoli@igalia.com> Cc: Tiezhu Yang <yangtiezhu@loongson.cn> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: linux-doc@vger.kernel.org Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20221117234328.594699-5-keescook@chromium.org Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/panic.c14
1 files changed, 14 insertions, 0 deletions
diff --git a/kernel/panic.c b/kernel/panic.c
index 0da47888f72e..e341366bd3e8 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -56,6 +56,7 @@ bool crash_kexec_post_notifiers;
int panic_on_warn __read_mostly;
unsigned long panic_on_taint;
bool panic_on_taint_nousertaint = false;
+static unsigned int warn_limit __read_mostly;
int panic_timeout = CONFIG_PANIC_TIMEOUT;
EXPORT_SYMBOL_GPL(panic_timeout);
@@ -85,6 +86,13 @@ static struct ctl_table kern_panic_table[] = {
.extra2 = SYSCTL_ONE,
},
#endif
+ {
+ .procname = "warn_limit",
+ .data = &warn_limit,
+ .maxlen = sizeof(warn_limit),
+ .mode = 0644,
+ .proc_handler = proc_douintvec,
+ },
{ }
};
@@ -194,8 +202,14 @@ static void panic_print_sys_info(void)
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);
+
+ if (atomic_inc_return(&warn_count) >= READ_ONCE(warn_limit) && warn_limit)
+ panic("%s: system warned too often (kernel.warn_limit is %d)",
+ origin, warn_limit);
}
/**