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 37ADD244691; Tue, 15 Jul 2025 13:50:00 +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=1752587400; cv=none; b=n1obS1d2hCNT8hFoatGjSXn0cw6vxDeh/q4moa2mJzzUAHJWZ/yYJHQKK3or/TNHIPZT1RLvsiWfro5Ky3I+BW00N7yz48MIsQr4hBX23Y+TBSB5oPaEjSg5CNDtRLPTVKHd4yB9WxTdp8Bz43nNRvXk/f5POKCx6xb6KVeP7bc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752587400; c=relaxed/simple; bh=4I4t2dpEWVA0KKgIKLBws4NKnH7aSN/ZZPb8MpTRtyc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=BdEpAryJKTQ5om6R+g0AJtXtTM9kNY6H5pTcBRzDFjRHkfJp57PE1WV4eYLVz7bd0uITFwRTqBkKvoE+IeNpN2HxOk7gWwjbsP9o7mAYNrdGLvjq73pHDnoUb9dmrMB7hVfVWHyvIpylxkui2Gb30GSCeuYyK8UGukAFE+mQ7eg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=PDfvRYe5; 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="PDfvRYe5" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 95D07C4CEE3; Tue, 15 Jul 2025 13:49:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1752587400; bh=4I4t2dpEWVA0KKgIKLBws4NKnH7aSN/ZZPb8MpTRtyc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PDfvRYe58yoLLIgLa0GqcoNwPmcJkX00acRaUkdOJIizHqhPuYfQeb3xDsrA1v8xF 5NUufM4vP3W8+w4S4OzeRtsAm8hfw8Pd5pl9mCjNW3g1D82QkKSrRY2QUBRBtTolB9 wcORdVAYjKWFSnt54XbhuXGVgsHKNe2gVp48vYk4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yeoreum Yun , Yunseong Kim , Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Byungchul Park , Dmitriy Vyukov , Sebastian Andrzej Siewior , Steven Rostedt , Vincenzo Frascino , Andrew Morton Subject: [PATCH 6.1 87/88] kasan: remove kasan_find_vm_area() to prevent possible deadlock Date: Tue, 15 Jul 2025 15:15:03 +0200 Message-ID: <20250715130758.060379814@linuxfoundation.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250715130754.497128560@linuxfoundation.org> References: <20250715130754.497128560@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev 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: Yeoreum Yun commit 6ee9b3d84775944fb8c8a447961cd01274ac671c upstream. find_vm_area() couldn't be called in atomic_context. If find_vm_area() is called to reports vm area information, kasan can trigger deadlock like: CPU0 CPU1 vmalloc(); alloc_vmap_area(); spin_lock(&vn->busy.lock) spin_lock_bh(&some_lock); spin_lock(&some_lock); kasan_report(); print_report(); print_address_description(); kasan_find_vm_area(); find_vm_area(); spin_lock(&vn->busy.lock) // deadlock! To prevent possible deadlock while kasan reports, remove kasan_find_vm_area(). Link: https://lkml.kernel.org/r/20250703181018.580833-1-yeoreum.yun@arm.com Fixes: c056a364e954 ("kasan: print virtual mapping info in reports") Signed-off-by: Yeoreum Yun Reported-by: Yunseong Kim Reviewed-by: Andrey Ryabinin Cc: Alexander Potapenko Cc: Andrey Konovalov Cc: Byungchul Park Cc: Dmitriy Vyukov Cc: Sebastian Andrzej Siewior Cc: Steven Rostedt Cc: Vincenzo Frascino Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- mm/kasan/report.c | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-) --- a/mm/kasan/report.c +++ b/mm/kasan/report.c @@ -337,17 +337,8 @@ static void print_address_description(vo } if (is_vmalloc_addr(addr)) { - struct vm_struct *va = find_vm_area(addr); - - if (va) { - pr_err("The buggy address belongs to the virtual mapping at\n" - " [%px, %px) created by:\n" - " %pS\n", - va->addr, va->addr + va->size, va->caller); - pr_err("\n"); - - page = vmalloc_to_page(addr); - } + pr_err("The buggy address %px belongs to a vmalloc virtual mapping\n", addr); + page = vmalloc_to_page(addr); } if (page) {