From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B3B00223C5C; Thu, 12 Dec 2024 16:36:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734021407; cv=none; b=bD5vynMlRt+PYj8VZ1OcSsaqKEH8PYb5+5rGN4LGjLmh/Ph/0tIMacqLjCgeDu4l9PLZJMo3YLJtlGcwmyQtau0D4QCcXV6EnN6QXvJWXHdFyLjSNnT+89mJpAZLx6qLNg3zRUasL9gncs1iGqblWV2+w1lW+ALU4M3eQH4MPmo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734021407; c=relaxed/simple; bh=CsZGV4bH1w19SIIifY4uEQ1ShfBfp5V1nswZ7Ve3O1A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=OsmSTmOeucd+dgV6TpxKk+H320IppsyaQ352enFFbXkWtzv/b5KTVTPHAayITCzo+8/yqHkYjhI9Agpr0Hcf52Q5cqvjRgen/KBQ0ALolsvUrGwybJEjgNulcwnPqIC6prMhz0k8Qbexigx29xHXHJYq28OJ5T2KaGHVIyGlEbo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=k9MKP0Vs; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="k9MKP0Vs" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 10E06C4CECE; Thu, 12 Dec 2024 16:36:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1734021407; bh=CsZGV4bH1w19SIIifY4uEQ1ShfBfp5V1nswZ7Ve3O1A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=k9MKP0VsJHkDts2ciEZ/BaHEYjs8/nkxPfcAuBJdnEAMnuJwbM9yGu+eO8i6NchrL WqOO5Y7kvQzKOy8Ty7zc4ADXkh23D5DK9ObhYSdPxSsAFpxA9fv3OZg662WNr+Zgn6 K4ZWjNRUn5W1geEupBgZ5VTuEXBvpA2MB8aZu5s8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jared Kangas , Alexander Potapenko , Andrey Konovalov , Andrey Ryabinin , Dmitry Vyukov , Vincenzo Frascino , Andrew Morton , Sasha Levin Subject: [PATCH 6.1 730/772] kasan: make report_lock a raw spinlock Date: Thu, 12 Dec 2024 16:01:15 +0100 Message-ID: <20241212144420.068931417@linuxfoundation.org> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20241212144349.797589255@linuxfoundation.org> References: <20241212144349.797589255@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jared Kangas [ Upstream commit e30a0361b8515d424c73c67de1a43e45a13b8ba2 ] If PREEMPT_RT is enabled, report_lock is a sleeping spinlock and must not be locked when IRQs are disabled. However, KASAN reports may be triggered in such contexts. For example: char *s = kzalloc(1, GFP_KERNEL); kfree(s); local_irq_disable(); char c = *s; /* KASAN report here leads to spin_lock() */ local_irq_enable(); Make report_spinlock a raw spinlock to prevent rescheduling when PREEMPT_RT is enabled. Link: https://lkml.kernel.org/r/20241119210234.1602529-1-jkangas@redhat.com Fixes: 342a93247e08 ("locking/spinlock: Provide RT variant header: ") Signed-off-by: Jared Kangas Cc: Alexander Potapenko Cc: Andrey Konovalov Cc: Andrey Ryabinin Cc: Dmitry Vyukov Cc: Vincenzo Frascino Cc: Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin --- mm/kasan/report.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/mm/kasan/report.c b/mm/kasan/report.c index 821cd12e8c8a7..6ad986c267b5e 100644 --- a/mm/kasan/report.c +++ b/mm/kasan/report.c @@ -173,7 +173,7 @@ static void update_kunit_status(bool sync) static void update_kunit_status(bool sync) { } #endif -static DEFINE_SPINLOCK(report_lock); +static DEFINE_RAW_SPINLOCK(report_lock); static void start_report(unsigned long *flags, bool sync) { @@ -185,7 +185,7 @@ static void start_report(unsigned long *flags, bool sync) lockdep_off(); /* Make sure we don't end up in loop. */ report_suppress_start(); - spin_lock_irqsave(&report_lock, *flags); + raw_spin_lock_irqsave(&report_lock, *flags); pr_err("==================================================================\n"); } @@ -195,7 +195,7 @@ static void end_report(unsigned long *flags, void *addr) trace_error_report_end(ERROR_DETECTOR_KASAN, (unsigned long)addr); pr_err("==================================================================\n"); - spin_unlock_irqrestore(&report_lock, *flags); + raw_spin_unlock_irqrestore(&report_lock, *flags); if (!test_bit(KASAN_BIT_MULTI_SHOT, &kasan_flags)) check_panic_on_warn("KASAN"); if (kasan_arg_fault == KASAN_ARG_FAULT_PANIC) -- 2.43.0