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 314A9388382 for ; Sat, 15 Aug 2026 06:40:29 +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=1786776030; cv=none; b=SxeF8PJ+joZKXaD6VKutsV/YH2wzV695iO6I8E5w1Zf7Y1N1j+HxXVMtct2YMJWbf1/kI/vhuWX6VZfjpLUJ7leukpkoeBxJoOm5bCiL1T2wgLnhjtUw3syVJOAjZMnJ++o2l3O9WIphV6x2lTidJrO+GyIGJyvJDkMrAZZqRvk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786776030; c=relaxed/simple; bh=9/jho2/bIxbQdDd05g0YpZJK2bGQknPQWyufpe76Sv4=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=HTEJrZpYKQ9C3O4H9P+fIn4rhmmkHH6A/2ssyBcxzoOHf2FEAGYoNE01BEamcvFp91IgCcYuOdSrzukBThOIJNjIeBEMao6A8we/sgfFD6zwE/3Dn10uwZHBKCpGK2CBgzraz4FbTWxlEKIKQo+jQvkBiNWy2sxAHz/dN1rZ9e0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=WWkMC0BW; 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="WWkMC0BW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7C16B1F000E9; Sat, 15 Aug 2026 06:40:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786776029; bh=oQN0NNGu5POn1EBRtNgmiGYVwUZ+ZQkx4YUx3ooz80A=; h=From:To:Cc:Subject:Date:Reply-To; b=WWkMC0BWV2Os1U5JPFDW9vMyw+5Uj/B/vWzL3MgRz+VMmZ+SaiWgXqJwJSlclE+YD uUiM0/JbinSrqBcBpThPvSWS5RibG7aVUT3ul4WJqWCCwwKfMC74M5+ScDC9Y3MWD7 t9Sk2eNMpWaEgCrt+2nTuuZAba1IgfwXFxRkhn3E= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-74436: rxrpc: serialize kernel accept preallocation with socket teardown Date: Sat, 15 Aug 2026 15:12:43 +0900 Message-ID: <2026081515-CVE-2026-74436-228e@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=3009; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=FEbNvdMx4Fd/59/jZAAQLQ3TAt8uvb5fEADAm+5pJwQ=; b=owGbwMvMwCRo6H6F97bub03G02pJDFkNjMrKMpHv1qsuKnLJL8o7pOt1uVvmi16l/JnLzH+mH X55q1KvI5aFQZCJQVZMkeXLNp6j+ysOKXoZ2p6GmcPKBDKEgYtTACYirMUwPzg09OPLTYu14qqX a/3786Nd6forYYb5zowXZyWunzCVP9WcM1vhtOgB2V+bAA== 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: rxrpc: serialize kernel accept preallocation with socket teardown rxrpc_kernel_charge_accept() reads rx->backlog without any socket/backlog synchronization and passes that raw pointer into rxrpc_service_prealloc_one(). A concurrent rxrpc_discard_prealloc() sets rx->backlog = NULL and frees the backlog rings, so a kernel preallocation worker can keep using a freed struct rxrpc_backlog while updating *_backlog_head/tail and array slots. Serialize the state check and backlog lookup with the socket lock, and reject kernel preallocation once teardown has disabled listening or discarded the service backlog. The Linux kernel CVE team has assigned CVE-2026-74436 to this issue. Affected and fixed versions =========================== Issue introduced in 4.9 with commit 00e907127e6f86d0f9b122d9b4347a8aa09a8b61 and fixed in 6.6.148 with commit 0337cdba0c477f176c0459bed012109453184573 Issue introduced in 4.9 with commit 00e907127e6f86d0f9b122d9b4347a8aa09a8b61 and fixed in 6.12.101 with commit dfa0b2bbc5e50119f89c6b5407faa5ed86dfa7c5 Issue introduced in 4.9 with commit 00e907127e6f86d0f9b122d9b4347a8aa09a8b61 and fixed in 6.18.40 with commit 35a967ff8b24db09ee429c39c5b5e6571639997d Issue introduced in 4.9 with commit 00e907127e6f86d0f9b122d9b4347a8aa09a8b61 and fixed in 7.1.5 with commit 1741378a7a83dfd8e53a9196730df709b903cd33 Issue introduced in 4.9 with commit 00e907127e6f86d0f9b122d9b4347a8aa09a8b61 and fixed in 7.2-rc1 with commit dc175389b18c29a5303ee83169ec653adfae3e17 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-2026-74436 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/rxrpc/call_accept.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/0337cdba0c477f176c0459bed012109453184573 https://git.kernel.org/stable/c/dfa0b2bbc5e50119f89c6b5407faa5ed86dfa7c5 https://git.kernel.org/stable/c/35a967ff8b24db09ee429c39c5b5e6571639997d https://git.kernel.org/stable/c/1741378a7a83dfd8e53a9196730df709b903cd33 https://git.kernel.org/stable/c/dc175389b18c29a5303ee83169ec653adfae3e17