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 5E9271D043E; Wed, 2 Oct 2024 13:43:38 +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=1727876618; cv=none; b=LzNmvGC0hdjRP8kTNKRPQBpTnUhTTvNb1TVTrONyEHfJ/wcXB6o1iIvnn5IOden8Oe3rp5cG78oIGAMJ28q1G5k1yV56i8Lmt5p1FaksPb8QsDB6nTIrufafue29ffPmESIuBM/90DdipN6Yx68wfDw7yBWcHPb8WSognmUfu5Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727876618; c=relaxed/simple; bh=2i2+CX3Q0Ll2JUl3/crGx8jOOpnSaKXjWsfY1zir+oA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=okmEK6QZotiqR47wXtZuZV/e+a81XBzThsz6aC3jRmw0pnR1QnHyuEhBJZfsvE1azx9P6+H6BYmJ/KMmeUPghGb3UYrrEKggKzLOwPpq3q2gSaccqmcwbx+L/hlo2rV5C25bAHowPA4siY07Z0zxkfx+r+QiGJAzb8QLBwYKysk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=YQD218An; 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="YQD218An" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DC310C4CEC5; Wed, 2 Oct 2024 13:43:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1727876618; bh=2i2+CX3Q0Ll2JUl3/crGx8jOOpnSaKXjWsfY1zir+oA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YQD218An9qpfsK4qAPE1D3zQ98EtDIu5aO7votvKl1CUgOwoc8ByTu+YISLIM2Se0 ih9sBi+F/PqIpMDKq4ywUUCC5qrrJFgWTRzUpC1cZ1vOIQs3CVjwvEtIqs34nlkR+H YQ4YfTznNhyGpOLE1ilam1wlHv3AQ6bhpV7AyWh8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, kernel test robot , Felix Moessbauer , Jens Axboe Subject: [PATCH 6.11 506/695] io_uring/sqpoll: retain test for whether the CPU is valid Date: Wed, 2 Oct 2024 14:58:24 +0200 Message-ID: <20241002125842.679673462@linuxfoundation.org> X-Mailer: git-send-email 2.46.2 In-Reply-To: <20241002125822.467776898@linuxfoundation.org> References: <20241002125822.467776898@linuxfoundation.org> User-Agent: quilt/0.67 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 6.11-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jens Axboe commit a09c17240bdf2e9fa6d0591afa9448b59785f7d4 upstream. A recent commit ensured that SQPOLL cannot be setup with a CPU that isn't in the current tasks cpuset, but it also dropped testing whether the CPU is valid in the first place. Without that, if a task passes in a CPU value that is too high, the following KASAN splat can get triggered: BUG: KASAN: stack-out-of-bounds in io_sq_offload_create+0x858/0xaa4 Read of size 8 at addr ffff800089bc7b90 by task wq-aff.t/1391 CPU: 4 UID: 1000 PID: 1391 Comm: wq-aff.t Not tainted 6.11.0-rc7-00227-g371c468f4db6 #7080 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace.part.0+0xcc/0xe0 show_stack+0x14/0x1c dump_stack_lvl+0x58/0x74 print_report+0x16c/0x4c8 kasan_report+0x9c/0xe4 __asan_report_load8_noabort+0x1c/0x24 io_sq_offload_create+0x858/0xaa4 io_uring_setup+0x1394/0x17c4 __arm64_sys_io_uring_setup+0x6c/0x180 invoke_syscall+0x6c/0x260 el0_svc_common.constprop.0+0x158/0x224 do_el0_svc+0x3c/0x5c el0_svc+0x34/0x70 el0t_64_sync_handler+0x118/0x124 el0t_64_sync+0x168/0x16c The buggy address belongs to stack of task wq-aff.t/1391 and is located at offset 48 in frame: io_sq_offload_create+0x0/0xaa4 This frame has 1 object: [32, 40) 'allowed_mask' The buggy address belongs to the virtual mapping at [ffff800089bc0000, ffff800089bc9000) created by: kernel_clone+0x124/0x7e0 The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff0000d740af80 pfn:0x11740a memcg:ffff0000c2706f02 flags: 0xbffe00000000000(node=0|zone=2|lastcpupid=0x1fff) raw: 0bffe00000000000 0000000000000000 dead000000000122 0000000000000000 raw: ffff0000d740af80 0000000000000000 00000001ffffffff ffff0000c2706f02 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff800089bc7a80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff800089bc7b00: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 >ffff800089bc7b80: 00 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff800089bc7c00: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 ffff800089bc7c80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f3 Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-lkp/202409161632.cbeeca0d-lkp@intel.com Fixes: f011c9cf04c0 ("io_uring/sqpoll: do not allow pinning outside of cpuset") Tested-by: Felix Moessbauer Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- io_uring/sqpoll.c | 2 ++ 1 file changed, 2 insertions(+) --- a/io_uring/sqpoll.c +++ b/io_uring/sqpoll.c @@ -465,6 +465,8 @@ __cold int io_sq_offload_create(struct i int cpu = p->sq_thread_cpu; ret = -EINVAL; + if (cpu >= nr_cpu_ids || !cpu_online(cpu)) + goto err_sqpoll; cpuset_cpus_allowed(current, &allowed_mask); if (!cpumask_test_cpu(cpu, &allowed_mask)) goto err_sqpoll;