From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx.swemel.ru (mx.swemel.ru [95.143.211.150]) (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 73B883955C3; Tue, 1 Sep 2026 09:05:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.143.211.150 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788253553; cv=none; b=X0JhHVKulEJMrnuZRAZEdQFDco4yjsMW74VZ0Yw065f70RdkcsHb/ky9kuAQxI1DBwreM5Z+Fi19Z7oy2qSnkvzFGkz1oSUmw+7SWBULWQpM6sew9/0EvnpJLGcitopi973/NMKjOGjHmmpa/h4GzBIqyr/g9ZIBAVsJSPl/JOM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788253553; c=relaxed/simple; bh=tx+BXv8FdJTOqroRusEgS7WxHl7Hlq864y2qJKfbL2A=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=eEusSfbgZBNItLEUbbpRfunUxxQLFkfhUsgXKzuxXh+gX1WvRnl2Zxa4ou/mlyd/yAV7tH0EMH+nCvXGsZ0oBW92X08nxWBMiQFr70kjRrmTSMxWe9nEnKkqL+WB2sTWj+cUKo2NNdha2RKrHQoQMhAPEn9UlJteoYlK66S6/uI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=swemel.ru; spf=pass smtp.mailfrom=swemel.ru; dkim=pass (1024-bit key) header.d=swemel.ru header.i=@swemel.ru header.b=JL9zg82M; arc=none smtp.client-ip=95.143.211.150 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=swemel.ru Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=swemel.ru Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=swemel.ru header.i=@swemel.ru header.b="JL9zg82M" From: Denis Arefev DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=swemel.ru; s=mail; t=1788253545; 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=bEnHDKcXLyTKDgscSQ2cRAL+7EnQmBfBqSJoXXxrq7k=; b=JL9zg82MHRd7pK9alIJ8BKW0UoCzNQGeWxrWNBThDPzERk0V38yvjJNLiHtLTTbydPacVa CHHVwxaOl0lzJUSSfXovZUoFvGd2y4skGGCsS0UhgbOOJ/YNjNYykH9MfHqwMFokH4nb7C 08V/FHs8sXir2kdJ7SmGgPqksuKqV8E= To: stable@vger.kernel.org, Greg Kroah-Hartman Cc: Karsten Graul , "David S. Miller" , Jakub Kicinski , Ursula Braun , linux-s390@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, "D . Wythe" , Larysa Zaremba , Wenjia Zhang Subject: [PATCH 5.10] net/smc: fix potential panic dues to unprotected smc_llc_srv_add_link() Date: Tue, 1 Sep 2026 12:05:43 +0300 Message-ID: <20260901090545.10419-1-arefev@swemel.ru> Precedence: bulk X-Mailing-List: linux-s390@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: "D. Wythe" commit e40b801b3603a8f90b46acbacdea3505c27f01c0 upstream. There is a certain chance to trigger the following panic: PID: 5900 TASK: ffff88c1c8af4100 CPU: 1 COMMAND: "kworker/1:48" #0 [ffff9456c1cc79a0] machine_kexec at ffffffff870665b7 #1 [ffff9456c1cc79f0] __crash_kexec at ffffffff871b4c7a #2 [ffff9456c1cc7ab0] crash_kexec at ffffffff871b5b60 #3 [ffff9456c1cc7ac0] oops_end at ffffffff87026ce7 #4 [ffff9456c1cc7ae0] page_fault_oops at ffffffff87075715 #5 [ffff9456c1cc7b58] exc_page_fault at ffffffff87ad0654 #6 [ffff9456c1cc7b80] asm_exc_page_fault at ffffffff87c00b62 [exception RIP: ib_alloc_mr+19] RIP: ffffffffc0c9cce3 RSP: ffff9456c1cc7c38 RFLAGS: 00010202 RAX: 0000000000000000 RBX: 0000000000000002 RCX: 0000000000000004 RDX: 0000000000000010 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff88c1ea281d00 R8: 000000020a34ffff R9: ffff88c1350bbb20 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000010 R14: ffff88c1ab040a50 R15: ffff88c1ea281d00 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #7 [ffff9456c1cc7c60] smc_ib_get_memory_region at ffffffffc0aff6df [smc] #8 [ffff9456c1cc7c88] smcr_buf_map_link at ffffffffc0b0278c [smc] #9 [ffff9456c1cc7ce0] __smc_buf_create at ffffffffc0b03586 [smc] The reason here is that when the server tries to create a second link, smc_llc_srv_add_link() has no protection and may add a new link to link group. This breaks the security environment protected by llc_conf_mutex. Fixes: 2d2209f20189 ("net/smc: first part of add link processing as SMC server") Signed-off-by: D. Wythe Reviewed-by: Larysa Zaremba Reviewed-by: Wenjia Zhang Signed-off-by: David S. Miller [Denis Arefev: adapted for 5.10: smc_llc_srv_add_link() has no req_qentry argument here, as SMC-Rv2 REQ_ADD_LINK support is not present in 5.10] Signed-off-by: Denis Arefev --- Backport fix for CVE-2023-54237 Link: https://nvd.nist.gov/vuln/detail/CVE-2023-54237 --- net/smc/af_smc.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index e9dabe758a31..e76e71417a2c 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -1303,8 +1303,10 @@ static int smcr_serv_conf_first_link(struct smc_sock *smc) smc_llc_link_active(link); smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE); + mutex_lock(&link->lgr->llc_conf_mutex); /* initial contact - try to establish second link */ smc_llc_srv_add_link(link); + mutex_unlock(&link->lgr->llc_conf_mutex); return 0; } -- 2.43.0