CVSS: -EPSS: 0%CPEs: 3EXPL: 0CVE-2021-47132 – mptcp: fix sk_forward_memory corruption on retransmission
https://notcve.org/view.php?id=CVE-2021-47132
In the Linux kernel, the following vulnerability has been resolved: mptcp: fix sk_forward_memory corruption on retransmission MPTCP sk_forward_memory handling is a bit special, as such field is protected by the msk socket spin_lock, instead of the plain socket lock. Currently we have a code path updating such field without handling the relevant lock: __mptcp_retrans() -> __mptcp_clean_una_wakeup() Several helpers in __mptcp_clean_una_wakeup() will update sk_forward_alloc, possibly causing such field corruption, as reported by Matthieu. Address the issue providing and using a new variant of blamed function which explicitly acquires the msk spin lock. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: mptcp: corrige la corrupción de sk_forward_memory en la retransmisión El manejo de MPTCP sk_forward_memory es un poco especial, ya que dicho campo está protegido por el socket msk spin_lock, en lugar del bloqueo de socket simple. Actualmente tenemos una ruta de código que actualiza dicho campo sin manejar el bloqueo relevante: __mptcp_retrans() -> __mptcp_clean_una_wakeup() Varios ayudantes en __mptcp_clean_una_wakeup() actualizarán sk_forward_alloc, posiblemente causando dicha corrupción de campo, según lo informado por Matthieu. Solucione el problema proporcionando y utilizando una nueva variante de la función culpada que adquiere explícitamente el bloqueo de giro msk. • https://git.kernel.org/stable/c/64b9cea7a0afe579dd2682f1f1c04f2e4e72fd25 https://git.kernel.org/stable/c/96db8ffef07516a6d7414b6988f2a4298a839977 https://git.kernel.org/stable/c/b9c78b1a95966a7bd2ddae05b73eafc0cda4fba3 https://git.kernel.org/stable/c/b5941f066b4ca331db225a976dae1d6ca8cf0ae3 •
CVSS: -EPSS: 0%CPEs: 3EXPL: 0CVE-2021-47131 – net/tls: Fix use-after-free after the TLS device goes down and up
https://notcve.org/view.php?id=CVE-2021-47131
In the Linux kernel, the following vulnerability has been resolved: net/tls: Fix use-after-free after the TLS device goes down and up When a netdev with active TLS offload goes down, tls_device_down is called to stop the offload and tear down the TLS context. However, the socket stays alive, and it still points to the TLS context, which is now deallocated. If a netdev goes up, while the connection is still active, and the data flow resumes after a number of TCP retransmissions, it will lead to a use-after-free of the TLS context. This commit addresses this bug by keeping the context alive until its normal destruction, and implements the necessary fallbacks, so that the connection can resume in software (non-offloaded) kTLS mode. On the TX side tls_sw_fallback is used to encrypt all packets. The RX side already has all the necessary fallbacks, because receiving non-decrypted packets is supported. The thing needed on the RX side is to block resync requests, which are normally produced after receiving non-decrypted packets. The necessary synchronization is implemented for a graceful teardown: first the fallbacks are deployed, then the driver resources are released (it used to be possible to have a tls_dev_resync after tls_dev_del). A new flag called TLS_RX_DEV_DEGRADED is added to indicate the fallback mode. • https://git.kernel.org/stable/c/e8f69799810c32dd40c6724d829eccc70baad07f https://git.kernel.org/stable/c/f1d4184f128dede82a59a841658ed40d4e6d3aa2 https://git.kernel.org/stable/c/0f1e6fe66977a864fe850522316f713d7b926fd9 https://git.kernel.org/stable/c/c55dcdd435aa6c6ad6ccac0a4c636d010ee367a4 •
CVSS: 4.4EPSS: 0%CPEs: 3EXPL: 0CVE-2021-47130 – nvmet: fix freeing unallocated p2pmem
https://notcve.org/view.php?id=CVE-2021-47130
In the Linux kernel, the following vulnerability has been resolved: nvmet: fix freeing unallocated p2pmem In case p2p device was found but the p2p pool is empty, the nvme target is still trying to free the sgl from the p2p pool instead of the regular sgl pool and causing a crash (BUG() is called). Instead, assign the p2p_dev for the request only if it was allocated from p2p pool. This is the crash that was caused: [Sun May 30 19:13:53 2021] ------------[ cut here ]------------ [Sun May 30 19:13:53 2021] kernel BUG at lib/genalloc.c:518! [Sun May 30 19:13:53 2021] invalid opcode: 0000 [#1] SMP PTI ... [Sun May 30 19:13:53 2021] kernel BUG at lib/genalloc.c:518! ... [Sun May 30 19:13:53 2021] RIP: 0010:gen_pool_free_owner+0xa8/0xb0 ... [Sun May 30 19:13:53 2021] Call Trace: [Sun May 30 19:13:53 2021] ------------[ cut here ]------------ [Sun May 30 19:13:53 2021] pci_free_p2pmem+0x2b/0x70 [Sun May 30 19:13:53 2021] pci_p2pmem_free_sgl+0x4f/0x80 [Sun May 30 19:13:53 2021] nvmet_req_free_sgls+0x1e/0x80 [nvmet] [Sun May 30 19:13:53 2021] kernel BUG at lib/genalloc.c:518! [Sun May 30 19:13:53 2021] nvmet_rdma_release_rsp+0x4e/0x1f0 [nvmet_rdma] [Sun May 30 19:13:53 2021] nvmet_rdma_send_done+0x1c/0x60 [nvmet_rdma] En el kernel de Linux, se resolvió la siguiente vulnerabilidad: nvmet: solución que libera p2pmem no asignado En caso de que se encuentre un dispositivo p2p pero el grupo p2p esté vacío, el objetivo nvme todavía está intentando liberar el sgl del grupo p2p en lugar del sgl normal. pool y provocando un bloqueo (se llama a BUG()). • https://git.kernel.org/stable/c/c6e3f13398123a008cd2ee28f93510b113a32791 https://git.kernel.org/stable/c/c440cd080761b18a52cac20f2a42e5da1e3995af https://git.kernel.org/stable/c/8a452d62e7cea3c8a2676a3b89a9118755a1a271 https://git.kernel.org/stable/c/bcd9a0797d73eeff659582f23277e7ab6e5f18f3 •
CVSS: 4.6EPSS: 0%CPEs: 4EXPL: 0CVE-2021-47129 – netfilter: nft_ct: skip expectations for confirmed conntrack
https://notcve.org/view.php?id=CVE-2021-47129
In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_ct: skip expectations for confirmed conntrack nft_ct_expect_obj_eval() calls nf_ct_ext_add() for a confirmed conntrack entry. However, nf_ct_ext_add() can only be called for !nf_ct_is_confirmed(). [ 1825.349056] WARNING: CPU: 0 PID: 1279 at net/netfilter/nf_conntrack_extend.c:48 nf_ct_xt_add+0x18e/0x1a0 [nf_conntrack] [ 1825.351391] RIP: 0010:nf_ct_ext_add+0x18e/0x1a0 [nf_conntrack] [ 1825.351493] Code: 41 5c 41 5d 41 5e 41 5f c3 41 bc 0a 00 00 00 e9 15 ff ff ff ba 09 00 00 00 31 f6 4c 89 ff e8 69 6c 3d e9 eb 96 45 31 ed eb cd <0f> 0b e9 b1 fe ff ff e8 86 79 14 e9 eb bf 0f 1f 40 00 0f 1f 44 00 [ 1825.351721] RSP: 0018:ffffc90002e1f1e8 EFLAGS: 00010202 [ 1825.351790] RAX: 000000000000000e RBX: ffff88814f5783c0 RCX: ffffffffc0e4f887 [ 1825.351881] RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffff88814f578440 [ 1825.351971] RBP: 0000000000000000 R08: 0000000000000000 R09: ffff88814f578447 [ 1825.352060] R10: ffffed1029eaf088 R11: 0000000000000001 R12: ffff88814f578440 [ 1825.352150] R13: ffff8882053f3a00 R14: 0000000000000000 R15: 0000000000000a20 [ 1825.352240] FS: 00007f992261c900(0000) GS:ffff889faec00000(0000) knlGS:0000000000000000 [ 1825.352343] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1825.352417] CR2: 000056070a4d1158 CR3: 000000015efe0000 CR4: 0000000000350ee0 [ 1825.352508] Call Trace: [ 1825.352544] nf_ct_helper_ext_add+0x10/0x60 [nf_conntrack] [ 1825.352641] nft_ct_expect_obj_eval+0x1b8/0x1e0 [nft_ct] [ 1825.352716] nft_do_chain+0x232/0x850 [nf_tables] Add the ct helper extension only for unconfirmed conntrack. Skip rule evaluation if the ct helper extension does not exist. Thus, you can only create expectations from the first packet. It should be possible to remove this limitation by adding a new action to attach a generic ct helper to the first packet. • https://git.kernel.org/stable/c/857b46027d6f91150797295752581b7155b9d0e1 https://git.kernel.org/stable/c/da8d31e80ff425f5a65dab7060d5c4aba749e562 https://git.kernel.org/stable/c/5f3429c05e4028a0e241afdad856dd15dec2ffb9 https://git.kernel.org/stable/c/2c0e6b35b88a961127066a1028bce9c727cbc3e5 https://git.kernel.org/stable/c/1710eb913bdcda3917f44d383c32de6bdabfc836 • CWE-273: Improper Check for Dropped Privileges •
CVSS: -EPSS: 0%CPEs: 3EXPL: 0CVE-2021-47128 – bpf, lockdown, audit: Fix buggy SELinux lockdown permission checks
https://notcve.org/view.php?id=CVE-2021-47128
In the Linux kernel, the following vulnerability has been resolved: bpf, lockdown, audit: Fix buggy SELinux lockdown permission checks Commit 59438b46471a ("security,lockdown,selinux: implement SELinux lockdown") added an implementation of the locked_down LSM hook to SELinux, with the aim to restrict which domains are allowed to perform operations that would breach lockdown. This is indirectly also getting audit subsystem involved to report events. The latter is problematic, as reported by Ondrej and Serhei, since it can bring down the whole system via audit: 1) The audit events that are triggered due to calls to security_locked_down() can OOM kill a machine, see below details [0]. 2) It also seems to be causing a deadlock via avc_has_perm()/slow_avc_audit() when trying to wake up kauditd, for example, when using trace_sched_switch() tracepoint, see details in [1]. Triggering this was not via some hypothetical corner case, but with existing tools like runqlat & runqslower from bcc, for example, which make use of this tracepoint. Rough call sequence goes like: rq_lock(rq) -> -------------------------+ trace_sched_switch() -> | bpf_prog_xyz() -> +-> deadlock selinux_lockdown() -> | audit_log_end() -> | wake_up_interruptible() -> | try_to_wake_up() -> | rq_lock(rq) --------------+ What's worse is that the intention of 59438b46471a to further restrict lockdown settings for specific applications in respect to the global lockdown policy is completely broken for BPF. • https://git.kernel.org/stable/c/59438b46471ae6cdfb761afc8c9beaf1e428a331 https://git.kernel.org/stable/c/ff5039ec75c83d2ed5b781dc7733420ee8c985fc https://git.kernel.org/stable/c/acc43fc6cf0d50612193813c5906a1ab9d433e1e https://git.kernel.org/stable/c/ff40e51043af63715ab413995ff46996ecf9583f •