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 5189A3C0B for ; Wed, 19 Jun 2024 13:36:38 +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=1718804198; cv=none; b=lB03H3sZU+SgrpYUwsjxBW8ZKFLqd5BpsExWfI5qWyJeeghTKI6ilKhP5scbtopkHIhS5DT5qnz+rGzy9w+JXpysInKBWHNXWQg1bVcH8+UfgpYIkwI5IhL11Dqqo5XJLLFslwRNiJV7RFG+zCczY9yQTA1U40sJXxQg3AaoiSw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718804198; c=relaxed/simple; bh=L+nXA/u/haZ6yYvb/t26ZfKpK57evKCr3QdFqiQ/Y7M=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=MFl4P8nAihQGPDrqD79SaFPk4N5VFHJCFG3SKwGSW8EepeA5M1xSs4yiRhnP1BdDBG22SpIrY0JSmPIONPNEfWc++sLhIDWBD3cC429dA8TaqIiaRsJzX8RMI8ZAiSz+eU/NjR3aow3yZ7/m0XuoeyB2GbYd9eeNaSG6EJn2JYY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=vdhobGGI; 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="vdhobGGI" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8B4CFC2BBFC; Wed, 19 Jun 2024 13:36:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1718804197; bh=L+nXA/u/haZ6yYvb/t26ZfKpK57evKCr3QdFqiQ/Y7M=; h=From:To:Cc:Subject:Date:Reply-to:From; b=vdhobGGIO3QVSr08HROUpIDXIOSLC3jvBMIo8AtizK0e5AfOVFC457x3H0NCiXNK8 yFmHjqg5JCYRun2flwOwC5NsPH7SiDqKoRjZOfG/oY0Ujd2HGrdM9JVXPOTBcVRFwZ NF5pQcAh7qGkPuJkd0VcYrsQ2FYTk4Vs8H++t8t0= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2024-38538: net: bridge: xmit: make sure we have at least eth header len bytes Date: Wed, 19 Jun 2024 15:35:47 +0200 Message-ID: <2024061947-CVE-2024-38538-e28a@gregkh> X-Mailer: git-send-email 2.45.2 Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Reply-to: , X-Developer-Signature: v=1; a=openpgp-sha256; l=4237; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=L+nXA/u/haZ6yYvb/t26ZfKpK57evKCr3QdFqiQ/Y7M=; b=owGbwMvMwCRo6H6F97bub03G02pJDGlF9zZbP43+abKSv3K1YvuU/G+e6bs2sbY9mtM/uzN+/ tkvjMszOmJZGASZGGTFFFm+bOM5ur/ikKKXoe1pmDmsTCBDGLg4BWAi/WEM86PLE2LvSUipdX77 FFh8035h2q3lQgzzY5gmCcwVlP+0IexT8y1GP0bnaXmVAA== X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit Description =========== In the Linux kernel, the following vulnerability has been resolved: net: bridge: xmit: make sure we have at least eth header len bytes syzbot triggered an uninit value[1] error in bridge device's xmit path by sending a short (less than ETH_HLEN bytes) skb. To fix it check if we can actually pull that amount instead of assuming. Tested with dropwatch: drop at: br_dev_xmit+0xb93/0x12d0 [bridge] (0xffffffffc06739b3) origin: software timestamp: Mon May 13 11:31:53 2024 778214037 nsec protocol: 0x88a8 length: 2 original length: 2 drop reason: PKT_TOO_SMALL [1] BUG: KMSAN: uninit-value in br_dev_xmit+0x61d/0x1cb0 net/bridge/br_device.c:65 br_dev_xmit+0x61d/0x1cb0 net/bridge/br_device.c:65 __netdev_start_xmit include/linux/netdevice.h:4903 [inline] netdev_start_xmit include/linux/netdevice.h:4917 [inline] xmit_one net/core/dev.c:3531 [inline] dev_hard_start_xmit+0x247/0xa20 net/core/dev.c:3547 __dev_queue_xmit+0x34db/0x5350 net/core/dev.c:4341 dev_queue_xmit include/linux/netdevice.h:3091 [inline] __bpf_tx_skb net/core/filter.c:2136 [inline] __bpf_redirect_common net/core/filter.c:2180 [inline] __bpf_redirect+0x14a6/0x1620 net/core/filter.c:2187 ____bpf_clone_redirect net/core/filter.c:2460 [inline] bpf_clone_redirect+0x328/0x470 net/core/filter.c:2432 ___bpf_prog_run+0x13fe/0xe0f0 kernel/bpf/core.c:1997 __bpf_prog_run512+0xb5/0xe0 kernel/bpf/core.c:2238 bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline] __bpf_prog_run include/linux/filter.h:657 [inline] bpf_prog_run include/linux/filter.h:664 [inline] bpf_test_run+0x499/0xc30 net/bpf/test_run.c:425 bpf_prog_test_run_skb+0x14ea/0x1f20 net/bpf/test_run.c:1058 bpf_prog_test_run+0x6b7/0xad0 kernel/bpf/syscall.c:4269 __sys_bpf+0x6aa/0xd90 kernel/bpf/syscall.c:5678 __do_sys_bpf kernel/bpf/syscall.c:5767 [inline] __se_sys_bpf kernel/bpf/syscall.c:5765 [inline] __x64_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5765 x64_sys_call+0x96b/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:322 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f The Linux kernel CVE team has assigned CVE-2024-38538 to this issue. Affected and fixed versions =========================== Issue introduced in 2.6.12 with commit 1da177e4c3f4 and fixed in 6.1.93 with commit 28126b83f86a Issue introduced in 2.6.12 with commit 1da177e4c3f4 and fixed in 6.6.33 with commit 1abb37114790 Issue introduced in 2.6.12 with commit 1da177e4c3f4 and fixed in 6.8.12 with commit f482fd4ce919 Issue introduced in 2.6.12 with commit 1da177e4c3f4 and fixed in 6.9.3 with commit 5b5d669f5698 Issue introduced in 2.6.12 with commit 1da177e4c3f4 and fixed in 6.10-rc1 with commit 8bd67ebb50c0 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-2024-38538 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/bridge/br_device.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/28126b83f86ab9cc7936029c2dff845d3dcedba2 https://git.kernel.org/stable/c/1abb371147905ba250b4cc0230c4be7e90bea4d5 https://git.kernel.org/stable/c/f482fd4ce919836a49012b2d31b00fc36e2488f2 https://git.kernel.org/stable/c/5b5d669f569807c7ab07546e73c0741845a2547a https://git.kernel.org/stable/c/8bd67ebb50c0145fd2ca8681ab65eb7e8cde1afc