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 E5F0E2EF28A; Tue, 17 Jun 2025 16:02:46 +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=1750176167; cv=none; b=Ga7wlAJbwZCH9XPqO/VEwmeoOiHZsFQNHgsDbHAZ2igoDKMHQGr7OhTYWs/xpCr7plMGBEGXXy72SYRLGLMPEYoAtm/VhjNuQs0CZzvcob5NASohKOfcO9O52jteQGnoDPMNgVk0Xx855WOebnjetBlT4YIoNTtP2HiP6+v1dR8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750176167; c=relaxed/simple; bh=DBY+sGN/MtYQOCdQiRxGXE/hvMUmo3cTMFwNBFjrSv0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JACc809wD6xc4ZzyX9c0jYJCvLkqVlwLP89Yf+wOsNZ8bUlqiOBgzk1XyugOIs/+C5JSf5rHOXnWo7Wq/Xe5QavH1KK2z9W5r1bBWC/zaE2WJpyHv014ihSsnZtScRdyEBjkGNfhHcre0bgddLuNZ88CkSA1Gat2mP1OPTyCtn4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=zXFZCdke; 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="zXFZCdke" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 558E7C4CEE7; Tue, 17 Jun 2025 16:02:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1750176166; bh=DBY+sGN/MtYQOCdQiRxGXE/hvMUmo3cTMFwNBFjrSv0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zXFZCdkecL+VEQ5tt7+5TQ4HwsRrxoXWb+f3+L3z5bLsQKE0wpbELI3g/v2oPaYBM Gb++oOvfILMwoRuYDvcsqqzGO0Ozmv+NGdvquvcJx4HOxY1ctfMgz2ZkRGdPOVs6g4 CO0ZFHphlqpOJRkXZkyIjS+eFM2oRjYyWNF0OyHQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+f0c4a4aba757549ae26c@syzkaller.appspotmail.com, Charalampos Mitrodimas , Tung Nguyen , Paolo Abeni , Sasha Levin Subject: [PATCH 6.6 245/356] net: tipc: fix refcount warning in tipc_aead_encrypt Date: Tue, 17 Jun 2025 17:26:00 +0200 Message-ID: <20250617152348.070114815@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250617152338.212798615@linuxfoundation.org> References: <20250617152338.212798615@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Charalampos Mitrodimas [ Upstream commit f29ccaa07cf3d35990f4d25028cc55470d29372b ] syzbot reported a refcount warning [1] caused by calling get_net() on a network namespace that is being destroyed (refcount=0). This happens when a TIPC discovery timer fires during network namespace cleanup. The recently added get_net() call in commit e279024617134 ("net/tipc: fix slab-use-after-free Read in tipc_aead_encrypt_done") attempts to hold a reference to the network namespace. However, if the namespace is already being destroyed, its refcount might be zero, leading to the use-after-free warning. Replace get_net() with maybe_get_net(), which safely checks if the refcount is non-zero before incrementing it. If the namespace is being destroyed, return -ENODEV early, after releasing the bearer reference. [1]: https://lore.kernel.org/all/68342b55.a70a0220.253bc2.0091.GAE@google.com/T/#m12019cf9ae77e1954f666914640efa36d52704a2 Reported-by: syzbot+f0c4a4aba757549ae26c@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/68342b55.a70a0220.253bc2.0091.GAE@google.com/T/#m12019cf9ae77e1954f666914640efa36d52704a2 Fixes: e27902461713 ("net/tipc: fix slab-use-after-free Read in tipc_aead_encrypt_done") Signed-off-by: Charalampos Mitrodimas Reviewed-by: Tung Nguyen Link: https://patch.msgid.link/20250527-net-tipc-warning-v2-1-df3dc398a047@posteo.net Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- net/tipc/crypto.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/net/tipc/crypto.c b/net/tipc/crypto.c index 8584893b47851..79f91b6ca8c84 100644 --- a/net/tipc/crypto.c +++ b/net/tipc/crypto.c @@ -818,7 +818,11 @@ static int tipc_aead_encrypt(struct tipc_aead *aead, struct sk_buff *skb, } /* Get net to avoid freed tipc_crypto when delete namespace */ - get_net(aead->crypto->net); + if (!maybe_get_net(aead->crypto->net)) { + tipc_bearer_put(b); + rc = -ENODEV; + goto exit; + } /* Now, do encrypt */ rc = crypto_aead_encrypt(req); -- 2.39.5