From:   Eric Biggers <ebiggers@kernel.org>
To:     stable@vger.kernel.org,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     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,
        Andrey Ryabinin <ryabinin.a.a@gmail.com>,
        Baoquan He <bhe@redhat.com>, Jonathan Corbet <corbet@lwn.net>,
        Xuefeng Li <lixuefeng@loongson.cn>,
        Tiezhu Yang <yangtiezhu@loongson.cn>,
        Marco Elver <elver@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linus Torvalds <torvalds@linux-foundation.org>
Subject: [PATCH 5.15 04/20] ubsan: no need to unset panic_on_warn in ubsan_epilogue()
Date:   Tue, 24 Jan 2023 10:50:54 -0800
Message-Id: <20230124185110.143857-5-ebiggers@kernel.org>
In-Reply-To: <20230124185110.143857-1-ebiggers@kernel.org>
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From: Tiezhu Yang <yangtiezhu@loongson.cn>

commit d83ce027a54068fabb70d2c252e1ce2da86784a4 upstream.

panic_on_warn is unset inside panic(), so no need to unset it before
calling panic() in ubsan_epilogue().

Link: https://lkml.kernel.org/r/1644324666-15947-5-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Xuefeng Li <lixuefeng@loongson.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 lib/ubsan.c | 10 +---------
 1 file changed, 1 insertion(+), 9 deletions(-)

diff --git a/lib/ubsan.c b/lib/ubsan.c
index bdc380ff5d5c7..36bd75e334263 100644
--- a/lib/ubsan.c
+++ b/lib/ubsan.c
@@ -154,16 +154,8 @@ static void ubsan_epilogue(void)
 
 	current->in_ubsan--;
 
-	if (panic_on_warn) {
-		/*
-		 * This thread may hit another WARN() in the panic path.
-		 * Resetting this prevents additional WARN() from panicking the
-		 * system on this thread.  Other threads are blocked by the
-		 * panic_mutex in panic().
-		 */
-		panic_on_warn = 0;
+	if (panic_on_warn)
 		panic("panic_on_warn set ...\n");
-	}
 }
 
 void __ubsan_handle_divrem_overflow(void *_data, void *lhs, void *rhs)
-- 
2.39.1