From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-177.mta0.migadu.com (out-177.mta0.migadu.com [91.218.175.177]) (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 CC21837F72E for ; Mon, 10 Aug 2026 22:01:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.177 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786399302; cv=none; b=N/DCul57nzyemCqzFRlLUgk5lzN22dsEoL3zwPaBPDUlA885b35cvvnMoU7FBG1DXdbmTS3jipH6z9/b7O8Ti6hSqijylkjdsakRA6deDJ+SrZtDyVoqE+P++Fzb2Nyw14ZZ7W24tyxcAIiwe4XtnDlq7DuA6id2yyxqzwoCKEc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786399302; c=relaxed/simple; bh=phV0KwrlePajk8LNhW2rjbcC1RPIsl5yAJCyvC44p9c=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=It9Z5Yms38T+b2q/SvpQgm25G80QBCJj57772QIrbexilVfl50XLMfXcOm4vfLNNgCb5qbASrPewJYtrvzNNTICzyBMz6V4a7TDVOPQ5o2W5Jw/hUv2FYmhOaFATen1JBb0CSYMKoD0Vn4koJvH5kxDAflCMjdFnGMUwJxg3Wws= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=lGCyq2wQ; arc=none smtp.client-ip=91.218.175.177 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="lGCyq2wQ" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1786399297; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=PyrIdg4szzBeqwEOb8e1kkMoiQYE51ro5vBtmXXm6I0=; b=lGCyq2wQPpDMDHuWS32gEfGeAi3Ll8aIwgO7APvAnZ+nl4H/iZgJuFDote/1HrB+PzMPDM 2CnK6FMgM6m2qsbKgCKv4A2swi1cIL7r+/W0qdMB2Hra2ZUU/yJder6XRJwVjKsUVq4mYS CTlbsO1eKJwBSDpdMCm6gmZC+WoSxBA= From: Zhu Yanjun To: jgg@ziepe.ca, leon@kernel.org, linux-rdma@vger.kernel.org, yanjun.zhu@linux.dev Cc: syzbot+72eddfbadda3e3928e72@syzkaller.appspotmail.com Subject: [PATCH v2 1/1] RDMA/cma: Fix WARNING in res_to_rt Date: Tue, 11 Aug 2026 00:01:23 +0200 Message-ID: <20260810220123.191696-1-yanjun.zhu@linux.dev> Precedence: bulk X-Mailing-List: linux-rdma@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT syzbot reported a WARN_ON(!res->dev) in res_to_rt() triggered via addr_handler() during asynchronous address resolution: " WARNING: drivers/infiniband/core/restrack.c:138 at res_to_rt+0x1c4/0x230 CPU#1: kworker/u8:4/59 Modules linked in: CPU: 1 UID: 0 PID: 59 Comm: kworker/u8:4 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Compute Engine, BIOS Google 07/24/2026 Workqueue: ib_addr process_one_req RIP: 0010:res_to_rt+0x1c4/0x230 drivers/infiniband/core/restrack.c:138 RSP: 0018:ffffc9000201f850 EFLAGS: 00010293 RAX: ffffffff88d00ce5 RBX: ffff88807f0fd4f8 RCX: ffff88801e6e0000 RDX: 0000000000000000 RSI: ffffffff8fd996f0 RDI: 0000000000000003 RBP: 0000000000000000 R08: ffff88801e6e0000 R09: 000000000000000a R10: 0000000000000009 R11: 0000000000000000 R12: dffffc0000000000 R13: 1ffff1100fe1fa9f R14: 0000000000000000 R15: 0000000000000003 FS: 0000000000000000(0000) GS:ffff888125012000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00001d559c3d2000 CR3: 0000000077c4c000 CR4: 00000000003526f0 Call Trace: rdma_restrack_add+0x5a/0x8a0 drivers/infiniband/core/restrack.c:236 addr_handler+0x41a/0x5a0 drivers/infiniband/core/cma.c:3534 process_one_req+0x2eb/0x540 drivers/infiniband/core/addr.c:624 process_one_work kernel/workqueue.c:3375 [inline] process_scheduled_works+0xc4e/0x1630 kernel/workqueue.c:3458 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3539 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 " In addr_handler(), cma_acquire_dev_by_src_ip() is called to populate id_priv->cma_dev and bind the associated ib_device to id_priv->id.device. If cma_acquire_dev_by_src_ip() returns an error (non-zero status), the ID remains unassociated with any RDMA device. Previously, rdma_restrack_add(&id_priv->res) was invoked unconditionally even when cma_acquire_dev_by_src_ip() failed, passing a resource with a NULL dev pointer and triggering the WARN_ON assertion in res_to_rt(). Fix this by only adding the resource to restrack when acquiring the device succeeds. Reported-by: syzbot+72eddfbadda3e3928e72@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=72eddfbadda3e3928e72 Tested-by: syzbot+72eddfbadda3e3928e72@syzkaller.appspotmail.com Fixes: cb5cd0ea4eb3 ("RDMA/core: Add CM to restrack after successful attachment to a device") Signed-off-by: Zhu Yanjun --- V1 -> V2: Follow Jason's advice to use if/else to handle this problem. --- drivers/infiniband/core/cma.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c index cc24fddf9aaa..73170b15fc3d 100644 --- a/drivers/infiniband/core/cma.c +++ b/drivers/infiniband/core/cma.c @@ -3528,10 +3528,12 @@ static void addr_handler(int status, struct sockaddr *src_addr, memcpy(addr, src_addr, rdma_addr_size(src_addr)); if (!status && !id_priv->cma_dev) { status = cma_acquire_dev_by_src_ip(id_priv); - if (status) + if (status) { pr_debug_ratelimited("RDMA CM: ADDR_ERROR: failed to acquire device. status %d\n", status); - rdma_restrack_add(&id_priv->res); + } else { + rdma_restrack_add(&id_priv->res); + } } else if (status) { pr_debug_ratelimited("RDMA CM: ADDR_ERROR: failed to resolve IP. status %d\n", status); } -- 2.43.0