From patchwork Mon Jun 17 16:27:08 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniil Dulov X-Patchwork-Id: 13701046 X-Patchwork-Delegate: kuba@kernel.org Received: from mail-out.aladdin-rd.ru (mail-out.aladdin-rd.ru [91.199.251.16]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9CA6820B3E; Mon, 17 Jun 2024 16:42:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.199.251.16 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718642589; cv=none; b=G/14lKUwR/4BC5wdUjUwpXI6tAJ73VYGbmGRF4qaTP0+ovdv2hl0KLLBElSZQ00n0NuhC3nxPMM31BBGFVlgC/BHSGA1tRHsYaA5nRHXGBuo8QQtv0aJPDAyNmhMH62oFefTkXF0UTy3wyJk20cAOwCUm/YX9lJCjXlyl+A019c= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718642589; c=relaxed/simple; bh=T66CKAQdjo08E7zecAEgrpzt9lx/5uvhDB/wmiDkH54=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=UIIm8uxAaR7lzgICaBy0T7DbgES9j89+c+4xJ0Y8MP3XHggYe2dHKaanrFRlO7fyqjKIX1vjC2NXWEgwEuBgqGfH/sfJ7fDGw9raKpX32cxlSw4S5BzwAaTKYiqDALHOE5cYma/UXaRGDGcUiOAiB/KmsRn8WXCP2lyh/jMB/r8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=aladdin.ru; spf=pass smtp.mailfrom=aladdin.ru; arc=none smtp.client-ip=91.199.251.16 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=aladdin.ru Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=aladdin.ru From: Daniil Dulov To: Alexei Starovoitov CC: Daniil Dulov , Daniel Borkmann , "David S. Miller" , Jakub Kicinski , Jesper Dangaard Brouer , John Fastabend , Eric Dumazet , Paolo Abeni , , , , Subject: [PATCH] xdp: remove WARN() from __xdp_reg_mem_model() Date: Mon, 17 Jun 2024 19:27:08 +0300 Message-ID: <20240617162708.492159-1-d.dulov@aladdin.ru> X-Mailer: git-send-email 2.25.1 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: EXCH-2016-02.aladdin.ru (192.168.1.102) To EXCH-2016-01.aladdin.ru (192.168.1.101) X-Patchwork-Delegate: kuba@kernel.org Syzkaller reports a warning in __xdp_reg_mem_model(). The warning occurs only if __mem_id_init_hash_table() returns an error. It returns the error in two cases: 1. memory allocation fails; 2. rhashtable_init() fails when some fields of rhashtable_params struct are not initialized properly. The second case cannot happen since there is a static const rhashtable_params struct with valid fields. So, warning is only triggered when there is a problem with memory allocation. Thus, there is no sense in using WARN() to handle this error and it can be safely removed. WARNING: CPU: 0 PID: 5065 at net/core/xdp.c:299 __xdp_reg_mem_model+0x2d9/0x650 net/core/xdp.c:299 CPU: 0 PID: 5065 Comm: syz-executor883 Not tainted 6.8.0-syzkaller-05271-gf99c5f563c17 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 RIP: 0010:__xdp_reg_mem_model+0x2d9/0x650 net/core/xdp.c:299 Call Trace: xdp_reg_mem_model+0x22/0x40 net/core/xdp.c:344 xdp_test_run_setup net/bpf/test_run.c:188 [inline] bpf_test_run_xdp_live+0x365/0x1e90 net/bpf/test_run.c:377 bpf_prog_test_run_xdp+0x813/0x11b0 net/bpf/test_run.c:1267 bpf_prog_test_run+0x33a/0x3b0 kernel/bpf/syscall.c:4240 __sys_bpf+0x48d/0x810 kernel/bpf/syscall.c:5649 __do_sys_bpf kernel/bpf/syscall.c:5738 [inline] __se_sys_bpf kernel/bpf/syscall.c:5736 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5736 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 Found by Linux Verification Center (linuxtesting.org) with Syzkaller. Fixes: 8d5d88527587 ("xdp: rhashtable with allocator ID to pointer mapping") Signed-off-by: Daniil Dulov Acked-by: Jesper Dangaard Brouer --- net/core/xdp.c | 1 - 1 file changed, 1 deletion(-) diff --git a/net/core/xdp.c b/net/core/xdp.c index 41693154e426..fb2f00e3f701 100644 --- a/net/core/xdp.c +++ b/net/core/xdp.c @@ -296,7 +296,6 @@ static struct xdp_mem_allocator *__xdp_reg_mem_model(struct xdp_mem_info *mem, ret = __mem_id_init_hash_table(); mutex_unlock(&mem_id_lock); if (ret < 0) { - WARN_ON(1); return ERR_PTR(ret); } }