From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 3B6A23F54C4 for ; Sat, 15 Aug 2026 12:33:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786797194; cv=none; b=qW/6m3BG7w3Q4o7K94ORUHplO4eq3gGvTxk0oHLVaCteo1ZshbbT9PeuiRsvFnLGGjhwyyeJKls5QBSdfyjrj8gH1vfGPzbF/4BdPFIgsiBixt8ogmuQSvhbNzB3nTZLXYnA1dMfFmNiVh6SzDFBLlONPqi1YtAX0jXwE7fMAIA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786797194; c=relaxed/simple; bh=1mZ5NRMqWbj8OUQsCNaSUYNNDbWZV27pPX/atfi5LNo=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=ennOLGUcRcMk7J4N4P/FlGvwZWNWgc/mMmNulHbbihhPWA47zpepPJHOhEI5kDq1JdtUByvyMIhd6qP0U3awi1YmhhDJVb/8Bk2G4tq4yHWWyNLUFBabans9NqB1yJYafej3W0TEzsoKkitBJxIzpxZHHukJ84Gjn1NL9HbPeiQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=hLkFL/Nl; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="hLkFL/Nl" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 92E7C1F000E9; Sat, 15 Aug 2026 12:33:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786797193; bh=pPh1wjVnSj5XbqjlRVE1hRKO6a1CD4paGHDKmKrMF88=; h=From:To:Cc:Subject:Date:Reply-To; b=hLkFL/NlFfE2zlVMizqSZ/dz4YJ2ZDBGb0/t8GVdaxuD/5BrzoP8MHNCCqM6lAgYh BRSBV0ezr3MbJlOYwFr+PhrUKTMYCKLggQEH4MmoREZlqh9LjfTDnBzEwZ8xHH4KSd OSm70ldvxxBGEGPtKrqz0brDkl22022Wgfy298Pc= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-74563: rds: tcp: hold the RCU lock across ipv6_chk_addr() in rds_tcp_laddr_check() Date: Sat, 15 Aug 2026 21:27:24 +0900 Message-ID: <2026081553-CVE-2026-74563-abb8@gregkh> X-Mailer: git-send-email 2.55.0 Reply-To: , Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=3753; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=JQRl3APMfQpX3CNhBx+t0IDOOjKp2cldV/beJxrRaW0=; b=owGbwMvMwCRo6H6F97bub03G02pJDFkNURf/Mob1CW7haTnA11g1cfelfXsm70lylnsls7hgw uEtZ012dMSyMAgyMciKKbJ82cZzdH/FIUUvQ9vTMHNYmUCGMHBxCsBEZjsxLFhWZ1k2taWqOqt8 7cneDWsEjy9ufMewYJZoMfcsPW/7VjOFzE/Xz4vNN4+YCgA= X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit From: Greg Kroah-Hartman Description =========== In the Linux kernel, the following vulnerability has been resolved: rds: tcp: hold the RCU lock across ipv6_chk_addr() in rds_tcp_laddr_check() rds_tcp_laddr_check() looks up a scoped IPv6 interface with dev_get_by_index_rcu(), drops the RCU read-side lock, and only then passes the bare struct net_device * into ipv6_chk_addr(). dev_get_by_index_rcu() only keeps the device alive within the same RCU read-side section. After rcu_read_unlock(), a concurrent RTM_DELLINK can free the net_device; ipv6_chk_addr() then dereferences the stale pointer in __ipv6_chk_addr_and_flags() (e.g. l3mdev_master_dev_rcu(dev)), reading freed memory. Keep the RCU read-side lock held across the ipv6_chk_addr() call instead of dropping it right after the lookup, so the device cannot be freed while it is in use. BUG: KASAN: slab-use-after-free in __ipv6_chk_addr_and_flags (... net/ipv6/addrconf.c:1998) Read of size 8 at addr ffff8880106ec000 by task exploit/153 Call Trace: ... kasan_report (mm/kasan/report.c:595) __ipv6_chk_addr_and_flags (... net/ipv6/addrconf.c:1998) ipv6_chk_addr (net/ipv6/addrconf.c:2031 net/ipv6/addrconf.c:1972) rds_tcp_laddr_check (net/rds/tcp.c:370) rds_bind (net/rds/bind.c:248) __sys_bind (net/socket.c:1920) __x64_sys_bind (net/socket.c:1956) do_syscall_64 (arch/x86/entry/syscall_64.c:63) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121) The Linux kernel CVE team has assigned CVE-2026-74563 to this issue. Affected and fixed versions =========================== Issue introduced in 4.19 with commit eee2fa6ab3225192d6d894c54a6fb02ac9efdff6 and fixed in 6.6.151 with commit 76dd48886eeeb5fcf2b837d2f4c3d17eebeac9ef Issue introduced in 4.19 with commit eee2fa6ab3225192d6d894c54a6fb02ac9efdff6 and fixed in 6.12.103 with commit f0d1fb05d70c8a561cd8d0473bcacafa2fc137ff Issue introduced in 4.19 with commit eee2fa6ab3225192d6d894c54a6fb02ac9efdff6 and fixed in 6.18.44 with commit b1d480fce05f857dc438080cd8c9244b84a83494 Issue introduced in 4.19 with commit eee2fa6ab3225192d6d894c54a6fb02ac9efdff6 and fixed in 7.1.8 with commit 8398bc477d3cb3e2b018a5aaac2bec0f69acda30 Issue introduced in 4.19 with commit eee2fa6ab3225192d6d894c54a6fb02ac9efdff6 and fixed in 7.2-rc6 with commit 78f75d632f74b8de0f081a128588f7c37d0d1164 Please see https://www.kernel.org for a full list of currently supported kernel versions by the kernel community. Unaffected versions might change over time as fixes are backported to older supported kernel versions. The official CVE entry at https://cve.org/CVERecord/?id=CVE-2026-74563 will be updated if fixes are backported, please check that for the most up to date information about this issue. Affected files ============== The file(s) affected by this issue are: net/rds/tcp.c Mitigation ========== The Linux kernel CVE team recommends that you update to the latest stable kernel version for this, and many other bugfixes. Individual changes are never tested alone, but rather are part of a larger kernel release. Cherry-picking individual commits is not recommended or supported by the Linux kernel community at all. If however, updating to the latest release is impossible, the individual changes to resolve this issue can be found at these commits: https://git.kernel.org/stable/c/76dd48886eeeb5fcf2b837d2f4c3d17eebeac9ef https://git.kernel.org/stable/c/f0d1fb05d70c8a561cd8d0473bcacafa2fc137ff https://git.kernel.org/stable/c/b1d480fce05f857dc438080cd8c9244b84a83494 https://git.kernel.org/stable/c/8398bc477d3cb3e2b018a5aaac2bec0f69acda30 https://git.kernel.org/stable/c/78f75d632f74b8de0f081a128588f7c37d0d1164