CVSS: 5.5EPSS: 0%CPEs: 6EXPL: 0CVE-2024-36938 – bpf, skmsg: Fix NULL pointer dereference in sk_psock_skb_ingress_enqueue
https://notcve.org/view.php?id=CVE-2024-36938
In the Linux kernel, the following vulnerability has been resolved: bpf, skmsg: Fix NULL pointer dereference in sk_psock_skb_ingress_enqueue Fix NULL pointer data-races in sk_psock_skb_ingress_enqueue() which syzbot reported [1]. [1] BUG: KCSAN: data-race in sk_psock_drop / sk_psock_skb_ingress_enqueue write to 0xffff88814b3278b8 of 8 bytes by task 10724 on cpu 1: sk_psock_stop_verdict net/core/skmsg.c:1257 [inline] sk_psock_drop+0x13e/0x1f0 net/core/skmsg.c:843 sk_psock_put include/linux/skmsg.h:459 [inline] sock_map_close+0x1a7/0x260 net/core/sock_map.c:1648 unix_release+0x4b/0x80 net/unix/af_unix.c:1048 __sock_release net/socket.c:659 [inline] sock_close+0x68/0x150 net/socket.c:1421 __fput+0x2c1/0x660 fs/file_table.c:422 __fput_sync+0x44/0x60 fs/file_table.c:507 __do_sys_close fs/open.c:1556 [inline] __se_sys_close+0x101/0x1b0 fs/open.c:1541 __x64_sys_close+0x1f/0x30 fs/open.c:1541 do_syscall_64+0xd3/0x1d0 entry_SYSCALL_64_after_hwframe+0x6d/0x75 read to 0xffff88814b3278b8 of 8 bytes by task 10713 on cpu 0: sk_psock_data_ready include/linux/skmsg.h:464 [inline] sk_psock_skb_ingress_enqueue+0x32d/0x390 net/core/skmsg.c:555 sk_psock_skb_ingress_self+0x185/0x1e0 net/core/skmsg.c:606 sk_psock_verdict_apply net/core/skmsg.c:1008 [inline] sk_psock_verdict_recv+0x3e4/0x4a0 net/core/skmsg.c:1202 unix_read_skb net/unix/af_unix.c:2546 [inline] unix_stream_read_skb+0x9e/0xf0 net/unix/af_unix.c:2682 sk_psock_verdict_data_ready+0x77/0x220 net/core/skmsg.c:1223 unix_stream_sendmsg+0x527/0x860 net/unix/af_unix.c:2339 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x140/0x180 net/socket.c:745 ____sys_sendmsg+0x312/0x410 net/socket.c:2584 ___sys_sendmsg net/socket.c:2638 [inline] __sys_sendmsg+0x1e9/0x280 net/socket.c:2667 __do_sys_sendmsg net/socket.c:2676 [inline] __se_sys_sendmsg net/socket.c:2674 [inline] __x64_sys_sendmsg+0x46/0x50 net/socket.c:2674 do_syscall_64+0xd3/0x1d0 entry_SYSCALL_64_after_hwframe+0x6d/0x75 value changed: 0xffffffff83d7feb0 -> 0x0000000000000000 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 10713 Comm: syz-executor.4 Tainted: G W 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Prior to this, commit 4cd12c6065df ("bpf, sockmap: Fix NULL pointer dereference in sk_psock_verdict_data_ready()") fixed one NULL pointer similarly due to no protection of saved_data_ready. Here is another different caller causing the same issue because of the same reason. So we should protect it with sk_callback_lock read lock because the writer side in the sk_psock_drop() uses "write_lock_bh(&sk->sk_callback_lock);". To avoid errors that could happen in future, I move those two pairs of lock into the sk_psock_data_ready(), which is suggested by John Fastabend. En el kernel de Linux, se resolvió la siguiente vulnerabilidad: bpf, skmsg: Se corrigió la desreferencia del puntero NULL en sk_psock_skb_ingress_enqueue Se corrigieron las ejecucións de datos del puntero NULL en sk_psock_skb_ingress_enqueue() que syzbot informó [1]. [1] ERROR: KCSAN: ejecución de datos en sk_psock_drop / sk_psock_skb_ingress_enqueue escribe en 0xffff88814b3278b8 de 8 bytes por tarea 10724 en la CPU 1: sk_psock_stop_verdict net/core/skmsg.c:1257 [en línea] 0 neto/núcleo/skmsg .c:843 sk_psock_put include/linux/skmsg.h:459 [en línea] sock_map_close+0x1a7/0x260 net/core/sock_map.c:1648 unix_release+0x4b/0x80 net/unix/af_unix.c:1048 __sock_release net/socket. c:659 [en línea] sock_close+0x68/0x150 net/socket.c:1421 __fput+0x2c1/0x660 fs/file_table.c:422 __fput_sync+0x44/0x60 fs/file_table.c:507 __do_sys_close fs/open.c:1556 [en línea] __se_sys_close+0x101/0x1b0 fs/open.c:1541 __x64_sys_close+0x1f/0x30 fs/open.c:1541 do_syscall_64+0xd3/0x1d0 Entry_SYSCALL_64_after_hwframe+0x6d/0x75 leer en 0xffff8881 4b3278b8 de 8 bytes por tarea 10713 en la CPU 0: sk_psock_data_ready include/linux/skmsg.h:464 [en línea] sk_psock_skb_ingress_enqueue+0x32d/0x390 net/core/skmsg.c:555 sk_psock_skb_ingress_self+0x185/0x1e0 net/core/skmsg.c:606 sk_psock_verdict_apply net /core/skmsg.c: 1008 [en línea] sk_psock_verdict_recv+0x3e4/0x4a0 net/core/skmsg.c:1202 unix_read_skb net/unix/af_unix.c:2546 [en línea] unix_stream_read_skb+0x9e/0xf0 net/unix/af_unix.c:2682 +0x77/0x220 net/core/skmsg.c:1223 unix_stream_sendmsg+0x527/0x860 net/unix/af_unix.c:2339 sock_sendmsg_nosec net/socket.c:730 [en línea] __sock_sendmsg+0x140/0x180 net/socket.c:745 ____sys_sendmsg+0x 312/ 0x410 net/socket.c:2584 ___sys_sendmsg net/socket.c:2638 [en línea] __sys_sendmsg+0x1e9/0x280 net/socket.c:2667 __do_sys_sendmsg net/socket.c:2676 [en línea] __se_sys_sendmsg net/socket. c:2674 [en línea] __x64_sys_sendmsg+0x46/0x50 net/socket.c:2674 do_syscall_64+0xd3/0x1d0 Entry_SYSCALL_64_after_hwframe+0x6d/0x75 valor cambiado: 0xffffffff83d7feb0 -> 0x0000000000000000 editado por Kernel Concurrency Sanitizer en: CPU: 0 PID: 10713 Comm: syz-executor .4 Contaminado: GW 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Nombre del hardware: Google Google Compute Engine/Google Compute Engine, BIOS Google 29/02/2024 Antes de esto, confirme 4cd12c6065df ("bpf, sockmap: corrija el puntero NULL dereference in sk_psock_verdict_data_ready()") arregló un puntero NULL de manera similar debido a que no hay protección de save_data_ready. Aquí hay otra persona que llama y causa el mismo problema por el mismo motivo. • https://git.kernel.org/stable/c/604326b41a6fb9b4a78b6179335decee0365cd8c https://git.kernel.org/stable/c/c0809c128dad4c3413818384eb06a341633db973 https://git.kernel.org/stable/c/5965bc7535fb87510b724e5465ccc1a1cf00916d https://git.kernel.org/stable/c/39dc9e1442385d6e9be0b6491ee488dddd55ae27 https://git.kernel.org/stable/c/b397a0ab8582c533ec0c6b732392f141fc364f87 https://git.kernel.org/stable/c/772d5729b5ff0df0d37b32db600ce635b2172f80 https://git.kernel.org/stable/c/6648e613226e18897231ab5e42ffc29e63fa3365 • CWE-476: NULL Pointer Dereference •
CVSS: -EPSS: 0%CPEs: 5EXPL: 0CVE-2024-36937 – xdp: use flags field to disambiguate broadcast redirect
https://notcve.org/view.php?id=CVE-2024-36937
In the Linux kernel, the following vulnerability has been resolved: xdp: use flags field to disambiguate broadcast redirect When redirecting a packet using XDP, the bpf_redirect_map() helper will set up the redirect destination information in struct bpf_redirect_info (using the __bpf_xdp_redirect_map() helper function), and the xdp_do_redirect() function will read this information after the XDP program returns and pass the frame on to the right redirect destination. When using the BPF_F_BROADCAST flag to do multicast redirect to a whole map, __bpf_xdp_redirect_map() sets the 'map' pointer in struct bpf_redirect_info to point to the destination map to be broadcast. And xdp_do_redirect() reacts to the value of this map pointer to decide whether it's dealing with a broadcast or a single-value redirect. However, if the destination map is being destroyed before xdp_do_redirect() is called, the map pointer will be cleared out (by bpf_clear_redirect_map()) without waiting for any XDP programs to stop running. This causes xdp_do_redirect() to think that the redirect was to a single target, but the target pointer is also NULL (since broadcast redirects don't have a single target), so this causes a crash when a NULL pointer is passed to dev_map_enqueue(). To fix this, change xdp_do_redirect() to react directly to the presence of the BPF_F_BROADCAST flag in the 'flags' value in struct bpf_redirect_info to disambiguate between a single-target and a broadcast redirect. And only read the 'map' pointer if the broadcast flag is set, aborting if that has been cleared out in the meantime. • https://git.kernel.org/stable/c/e624d4ed4aa8cc3c69d1359b0aaea539203ed266 https://git.kernel.org/stable/c/12481f30128fbebc2eeb55eb2d56390fdfa30c5e https://git.kernel.org/stable/c/272bfb019f3cc018f654b992115774e77b4f3ffc https://git.kernel.org/stable/c/e22e25820fa04ea5eaac4ef7ee200e9923f466a4 https://git.kernel.org/stable/c/6fd81f9d333e7b3532036577b1beb74ba1323553 https://git.kernel.org/stable/c/5bcf0dcbf9066348058b88a510c57f70f384c92c •
CVSS: 5.5EPSS: 0%CPEs: 4EXPL: 0CVE-2024-36936 – efi/unaccepted: touch soft lockup during memory accept
https://notcve.org/view.php?id=CVE-2024-36936
In the Linux kernel, the following vulnerability has been resolved: efi/unaccepted: touch soft lockup during memory accept Commit 50e782a86c98 ("efi/unaccepted: Fix soft lockups caused by parallel memory acceptance") has released the spinlock so other CPUs can do memory acceptance in parallel and not triggers softlockup on other CPUs. However the softlock up was intermittent shown up if the memory of the TD guest is large, and the timeout of softlockup is set to 1 second: RIP: 0010:_raw_spin_unlock_irqrestore Call Trace: ? __hrtimer_run_queues <IRQ> ? hrtimer_interrupt ? watchdog_timer_fn ? __sysvec_apic_timer_interrupt ? • https://git.kernel.org/stable/c/50e782a86c980d4f8292ef82ed8139282ca07a98 https://git.kernel.org/stable/c/b583bfcc5a36dbd1db1984dbfcfd23ba64d23604 https://git.kernel.org/stable/c/e115c1b5de55a105c75aba8eb08301c075fa4ef4 https://git.kernel.org/stable/c/781e34b736014188ba9e46a71535237313dcda81 https://git.kernel.org/stable/c/1c5a1627f48105cbab81d25ec2f72232bfaa8185 https://access.redhat.com/security/cve/CVE-2024-36936 https://bugzilla.redhat.com/show_bug.cgi?id=2296278 •
CVSS: -EPSS: 0%CPEs: 8EXPL: 0CVE-2024-36934 – bna: ensure the copied buf is NUL terminated
https://notcve.org/view.php?id=CVE-2024-36934
In the Linux kernel, the following vulnerability has been resolved: bna: ensure the copied buf is NUL terminated Currently, we allocate a nbytes-sized kernel buffer and copy nbytes from userspace to that buffer. Later, we use sscanf on this buffer but we don't ensure that the string is terminated inside the buffer, this can lead to OOB read when using sscanf. Fix this issue by using memdup_user_nul instead of memdup_user. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: bna: asegúrese de que el buf copiado tenga terminación NUL. Actualmente, asignamos un búfer del kernel de tamaño nbytes y copiamos nbytes del espacio de usuario a ese búfer. • https://git.kernel.org/stable/c/7afc5dbde09104b023ce04465ba71aaba0fc4346 https://git.kernel.org/stable/c/bd502ba81cd1d515deddad7dbc6b812b14b97147 https://git.kernel.org/stable/c/80578ec10335bc15ac35fd1703c22aab34e39fdd https://git.kernel.org/stable/c/6f0f19b79c085cc891c418b768f26f7004bd51a4 https://git.kernel.org/stable/c/0f560240b4cc25d3de527deb257cdf072c0102a9 https://git.kernel.org/stable/c/06cb37e2ba6441888f24566a997481d4197b4e32 https://git.kernel.org/stable/c/e19478763154674c084defc62ae0d64d79657f91 https://git.kernel.org/stable/c/1518b2b498a0109eb6b15755169d3b660 •
CVSS: 5.9EPSS: 0%CPEs: 8EXPL: 0CVE-2024-36933 – nsh: Restore skb->{protocol,data,mac_header} for outer header in nsh_gso_segment().
https://notcve.org/view.php?id=CVE-2024-36933
In the Linux kernel, the following vulnerability has been resolved: nsh: Restore skb->{protocol,data,mac_header} for outer header in nsh_gso_segment(). syzbot triggered various splats (see [0] and links) by a crafted GSO packet of VIRTIO_NET_HDR_GSO_UDP layering the following protocols: ETH_P_8021AD + ETH_P_NSH + ETH_P_IPV6 + IPPROTO_UDP NSH can encapsulate IPv4, IPv6, Ethernet, NSH, and MPLS. As the inner protocol can be Ethernet, NSH GSO handler, nsh_gso_segment(), calls skb_mac_gso_segment() to invoke inner protocol GSO handlers. nsh_gso_segment() does the following for the original skb before calling skb_mac_gso_segment() 1. reset skb->network_header 2. save the original skb->{mac_heaeder,mac_len} in a local variable 3. pull the NSH header 4. resets skb->mac_header 5. set up skb->mac_len and skb->protocol for the inner protocol. and does the following for the segmented skb 6. set ntohs(ETH_P_NSH) to skb->protocol 7. push the NSH header 8. restore skb->mac_header 9. set skb->mac_header + mac_len to skb->network_header 10. restore skb->mac_len There are two problems in 6-7 and 8-9. (a) After 6 & 7, skb->data points to the NSH header, so the outer header (ETH_P_8021AD in this case) is stripped when skb is sent out of netdev. Also, if NSH is encapsulated by NSH + Ethernet (so NSH-Ethernet-NSH), skb_pull() in the first nsh_gso_segment() will make skb->data point to the middle of the outer NSH or Ethernet header because the Ethernet header is not pulled by the second nsh_gso_segment(). (b) While restoring skb->{mac_header,network_header} in 8 & 9, nsh_gso_segment() does not assume that the data in the linear buffer is shifted. However, udp6_ufo_fragment() could shift the data and change skb->mac_header accordingly as demonstrated by syzbot. If this happens, even the restored skb->mac_header points to the middle of the outer header. It seems nsh_gso_segment() has never worked with outer headers so far. At the end of nsh_gso_segment(), the outer header must be restored for the segmented skb, instead of the NSH header. To do that, let's calculate the outer header position relatively from the inner header and set skb->{data,mac_header,protocol} properly. [0]: BUG: KMSAN: uninit-value in ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:524 [inline] BUG: KMSAN: uninit-value in ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:602 [inline] BUG: KMSAN: uninit-value in ipvlan_queue_xmit+0xf44/0x16b0 drivers/net/ipvlan/ipvlan_core.c:668 ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:524 [inline] ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:602 [inline] ipvlan_queue_xmit+0xf44/0x16b0 drivers/net/ipvlan/ipvlan_core.c:668 ipvlan_start_xmit+0x5c/0x1a0 drivers/net/ipvlan/ipvlan_main.c:222 __netdev_start_xmit include/linux/netdevice.h:4989 [inline] netdev_start_xmit include/linux/netdevice.h:5003 [inline] xmit_one net/core/dev.c:3547 [inline] dev_hard_start_xmit+0x244/0xa10 net/core/dev.c:3563 __dev_queue_xmit+0x33ed/0x51c0 net/core/dev.c:4351 dev_queue_xmit include/linux/netdevice.h:3171 [inline] packet_xmit+0x9c/0x6b0 net/packet/af_packet.c:276 packet_snd net/packet/af_packet.c:3081 [inline] packet_sendmsg+0x8aef/0x9f10 net/packet/af_packet.c:3113 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x735/0xa10 net/socket.c:2191 __do_sys_sendto net/socket.c:2203 [inline] __se_sys_sendto net/socket.c:2199 [inline] __x64_sys_sendto+0x125/0x1c0 net/socket.c:2199 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+0x63/0x6b Uninit was created at: slab_post_alloc_hook mm/slub.c:3819 [inline] slab_alloc_node mm/slub.c:3860 [inline] __do_kmalloc_node mm/slub.c:3980 [inline] __kmalloc_node_track_caller+0x705/0x1000 mm/slub.c:4001 kmalloc_reserve+0x249/0x4a0 net/core/skbuff.c:582 __ ---truncated--- En el kernel de Linux, se resolvió la siguiente vulnerabilidad: nsh: restaurar skb->{protocol,data,mac_header} para el encabezado externo en nsh_gso_segment(). syzbot activó varios símbolos (ver [0] y enlaces) mediante un paquete GSO manipulado de VIRTIO_NET_HDR_GSO_UDP que superpone los siguientes protocolos: ETH_P_8021AD + ETH_P_NSH + ETH_P_IPV6 + IPPROTO_UDP NSH puede encapsular IPv4, IPv6, Ethernet, NSH y MPLS. Como el protocolo interno puede ser Ethernet, el controlador NSH GSO, nsh_gso_segment(), llama a skb_mac_gso_segment() para invocar los controladores GSO del protocolo interno. nsh_gso_segment() hace lo siguiente para el skb original antes de llamar a skb_mac_gso_segment() 1. restablecer skb->network_header 2. guardar el skb->{mac_heaeder,mac_len} original en una variable local 3. extraer el encabezado NSH 4. restablece skb- >mac_header 5. Configure skb->mac_len y skb->protocol para el protocolo interno. y hace lo siguiente para el skb segmentado 6. configurar ntohs(ETH_P_NSH) en skb->protocol 7. empujar el encabezado NSH 8. restaurar skb->mac_header 9. configurar skb->mac_header + mac_len en skb->network_header 10. restaurar skb->mac_len Hay dos problemas en 6-7 y 8-9. (a) Después de 6 y 7, skb->data apunta al encabezado NSH, por lo que el encabezado externo (ETH_P_8021AD en este caso) se elimina cuando skb se envía fuera de netdev. • https://git.kernel.org/stable/c/c411ed854584a71b0e86ac3019b60e4789d88086 https://git.kernel.org/stable/c/a7c2c3c1caabcb4a3d6c47284c397507aaf54fe9 https://git.kernel.org/stable/c/46134031c20fd313d03b90169d64b2e05ca6b65c https://git.kernel.org/stable/c/bbccf0caef2fa917d6d0692385a06ce3c262a216 https://git.kernel.org/stable/c/5a4603fbc285752d19e4b415466db18ef3617e4a https://git.kernel.org/stable/c/37ed6f244ec5bda2e90b085084e322ea55d0aaa2 https://git.kernel.org/stable/c/696d18bb59727a2e0526c0802a812620be1c9340 https://git.kernel.org/stable/c/29a07f2ee4d273760c2acbfc756e29ecc • CWE-457: Use of Uninitialized Variable •