CVSS: -EPSS: 0%CPEs: 4EXPL: 0CVE-2021-47597 – inet_diag: fix kernel-infoleak for UDP sockets
https://notcve.org/view.php?id=CVE-2021-47597
In the Linux kernel, the following vulnerability has been resolved: inet_diag: fix kernel-infoleak for UDP sockets KMSAN reported a kernel-infoleak [1], that can exploited by unpriv users. After analysis it turned out UDP was not initializing r->idiag_expires. Other users of inet_sk_diag_fill() might make the same mistake in the future, so fix this in inet_sk_diag_fill(). [1] BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:121 [inline] BUG: KMSAN: kernel-infoleak in copyout lib/iov_iter.c:156 [inline] BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x69d/0x25c0 lib/iov_iter.c:670 instrument_copy_to_user include/linux/instrumented.h:121 [inline] copyout lib/iov_iter.c:156 [inline] _copy_to_iter+0x69d/0x25c0 lib/iov_iter.c:670 copy_to_iter include/linux/uio.h:155 [inline] simple_copy_to_iter+0xf3/0x140 net/core/datagram.c:519 __skb_datagram_iter+0x2cb/0x1280 net/core/datagram.c:425 skb_copy_datagram_iter+0xdc/0x270 net/core/datagram.c:533 skb_copy_datagram_msg include/linux/skbuff.h:3657 [inline] netlink_recvmsg+0x660/0x1c60 net/netlink/af_netlink.c:1974 sock_recvmsg_nosec net/socket.c:944 [inline] sock_recvmsg net/socket.c:962 [inline] sock_read_iter+0x5a9/0x630 net/socket.c:1035 call_read_iter include/linux/fs.h:2156 [inline] new_sync_read fs/read_write.c:400 [inline] vfs_read+0x1631/0x1980 fs/read_write.c:481 ksys_read+0x28c/0x520 fs/read_write.c:619 __do_sys_read fs/read_write.c:629 [inline] __se_sys_read fs/read_write.c:627 [inline] __x64_sys_read+0xdb/0x120 fs/read_write.c:627 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x44/0xae Uninit was created at: slab_post_alloc_hook mm/slab.h:524 [inline] slab_alloc_node mm/slub.c:3251 [inline] __kmalloc_node_track_caller+0xe0c/0x1510 mm/slub.c:4974 kmalloc_reserve net/core/skbuff.c:354 [inline] __alloc_skb+0x545/0xf90 net/core/skbuff.c:426 alloc_skb include/linux/skbuff.h:1126 [inline] netlink_dump+0x3d5/0x16a0 net/netlink/af_netlink.c:2245 __netlink_dump_start+0xd1c/0xee0 net/netlink/af_netlink.c:2370 netlink_dump_start include/linux/netlink.h:254 [inline] inet_diag_handler_cmd+0x2e7/0x400 net/ipv4/inet_diag.c:1343 sock_diag_rcv_msg+0x24a/0x620 netlink_rcv_skb+0x447/0x800 net/netlink/af_netlink.c:2491 sock_diag_rcv+0x63/0x80 net/core/sock_diag.c:276 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x1095/0x1360 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x16f3/0x1870 net/netlink/af_netlink.c:1916 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg net/socket.c:724 [inline] sock_write_iter+0x594/0x690 net/socket.c:1057 do_iter_readv_writev+0xa7f/0xc70 do_iter_write+0x52c/0x1500 fs/read_write.c:851 vfs_writev fs/read_write.c:924 [inline] do_writev+0x63f/0xe30 fs/read_write.c:967 __do_sys_writev fs/read_write.c:1040 [inline] __se_sys_writev fs/read_write.c:1037 [inline] __x64_sys_writev+0xe5/0x120 fs/read_write.c:1037 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x44/0xae Bytes 68-71 of 312 are uninitialized Memory access of size 312 starts at ffff88812ab54000 Data copied to user address 0000000020001440 CPU: 1 PID: 6365 Comm: syz-executor801 Not tainted 5.16.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 En el kernel de Linux, se resolvió la siguiente vulnerabilidad: inet_diag: corrige la fuga de información del kernel para sockets UDP KMSAN informó una fuga de información del kernel [1], que puede ser explotada por usuarios sin privilegios. Después del análisis resultó que UDP no estaba inicializando r->idiag_expires. Otros usuarios de inet_sk_diag_fill() podrían cometer el mismo error en el futuro, así que solucione este problema en inet_sk_diag_fill(). [1] ERROR: KMSAN: kernel-infoleak en instrument_copy_to_user include/linux/instrumented.h:121 [en línea] ERROR: KMSAN: kernel-infoleak en copia lib/iov_iter.c:156 [en línea] ERROR: KMSAN: kernel-infoleak en _copy_to_iter+0x69d/0x25c0 lib/iov_iter.c:670 instrument_copy_to_user include/linux/instrumented.h:121 [en línea] copia lib/iov_iter.c:156 [en línea] _copy_to_iter+0x69d/0x25c0 lib/iov_iter.c:670 copy_to_iter include/linux/uio.h:155 [en línea] simple_copy_to_iter+0xf3/0x140 net/core/datagram.c:519 __skb_datagram_iter+0x2cb/0x1280 net/core/datagram.c:425 skb_copy_datagram_iter+0xdc/0x270 net/core/datagram .c:533 skb_copy_datagram_msg include/linux/skbuff.h:3657 [en línea] netlink_recvmsg+0x660/0x1c60 net/netlink/af_netlink.c:1974 sock_recvmsg_nosec net/socket.c:944 [en línea] sock_recvmsg net/socket.c:962 [en línea] sock_read_iter+0x5a9/0x630 net/socket.c:1035 call_read_iter include/linux/fs.h:2156 [en línea] new_sync_read fs/read_write.c:400 [en línea] vfs_read+0x1631/0x1980 fs/read_write.c: 481 ksys_read+0x28c/0x520 fs/read_write.c:619 __do_sys_read fs/read_write.c:629 [en línea] __se_sys_read fs/read_write.c:627 [en línea] __x64_sys_read+0xdb/0x120 fs/read_write.c:627 _arco x64/ x86/entry/common.c:51 [en línea] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 Entry_SYSCALL_64_after_hwframe+0x44/0xae Uninit se creó en: slab_post_alloc_hook mm/slab.h:524 [en línea] slab_alloc_node mm/slub.c:3251 [en línea] __kmalloc_node_track_caller+0xe0c/0x1510 mm/slub.c:4974 kmalloc_reserve net/core/skbuff.c:354 [en línea] __alloc_skb+0x545/0xf90 net/core/skbuff.c:426 alloc_skb include/linux/skbuff.h:1126 [en línea] netlink_dump+0x3d5/0x16a0 net/netlink/af_netlink.c:2245 __netlink_dump_start+0xd1c/0xee0 net/netlink/af_netlink.c:2370 netlink_dump_start include/linux/netlink.h:254 [en línea] inet_diag_handler_cmd+0x2e7/0x400 net/ipv4/inet_diag.c:1343 sock_diag_rcv_msg+0x24a/0x620 netlink_rcv_skb+0x447/0x800 net/netlink/af_netlink.c:2491 sock_diag_rcv+0x63/0x80 net/core/sock_diag.c:276 netlink_unicast_kernel net/netlink/af_netlink.c: 1319 [en línea] netlink_unicast+0x1095/0x1360 netLink/af_netlink.c: 1345 netlink_sendmsg+0x16f3/0x1870 net/netlink/af_etlink.c: 1916 sockm. C: 704 [ en línea] sock_sendmsg net/socket.c:724 [en línea] sock_write_iter+0x594/0x690 net/socket.c:1057 do_iter_readv_writev+0xa7f/0xc70 do_iter_write+0x52c/0x1500 fs/read_write.c:851 vfs_writev fs/read_write.c:9 24 [en línea] do_writev+0x63f/0xe30 fs/read_write.c:967 __do_sys_writev fs/read_write.c:1040 [en línea] __se_sys_writev fs/read_write.c:1037 [en línea] __x64_sys_writev+0xe5/0x120 fs/read_write.c:1037 _syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 Entry_SYSCALL_64_after_hwframe+0x44/0xae Los bytes 68-71 de 312 no están inicializados El acceso a la memoria de tamaño 312 comienza en ffff88812ab54000 Datos copiados a la dirección de usuario 0000000020001440 CPU: 1 PID: 6365 Comm: syz-executor801 Not tainted 5.16.0-rc3-syzkaller #0 Nombre de hardware: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 • https://git.kernel.org/stable/c/3c4d05c8056724aff3abc20650807dd828fded54 https://git.kernel.org/stable/c/7b5596e531253ce84213d9daa7120b71c9d83198 https://git.kernel.org/stable/c/3a4f6dba1eb98101abc012ef968a8b10dac1ce50 https://git.kernel.org/stable/c/e5d28205bf1de7082d904ed277ceb2db2879e302 https://git.kernel.org/stable/c/71ddeac8cd1d217744a0e060ff520e147c9328d1 •
CVSS: 7.3EPSS: 0%CPEs: 3EXPL: 0CVE-2021-47596 – net: hns3: fix use-after-free bug in hclgevf_send_mbx_msg
https://notcve.org/view.php?id=CVE-2021-47596
In the Linux kernel, the following vulnerability has been resolved: net: hns3: fix use-after-free bug in hclgevf_send_mbx_msg Currently, the hns3_remove function firstly uninstall client instance, and then uninstall acceletion engine device. The netdevice is freed in client instance uninstall process, but acceletion engine device uninstall process still use it to trace runtime information. This causes a use after free problem. So fixes it by check the instance register state to avoid use after free. En el kernel de Linux, se resolvió la siguiente vulnerabilidad: net: hns3: corrige el error de use-after-free en hclgevf_send_mbx_msg Actualmente, la función hns3_remove desinstala primero la instancia del cliente y luego desinstala el dispositivo del motor de aceleración. El dispositivo de red se libera en el proceso de desinstalación de la instancia del cliente, pero el proceso de desinstalación del dispositivo del motor de aceleración aún lo utiliza para rastrear la información del tiempo de ejecución. • https://git.kernel.org/stable/c/d8355240cf8fb8b9e002b5c8458578435cea85c2 https://git.kernel.org/stable/c/12512bc8f25b8ba9795dfbae0e9ca57ff13fd542 https://git.kernel.org/stable/c/4f4a353f6fe033807cd026a5de81c67469ff19b0 https://git.kernel.org/stable/c/27cbf64a766e86f068ce6214f04c00ceb4db1af4 https://access.redhat.com/security/cve/CVE-2021-47596 https://bugzilla.redhat.com/show_bug.cgi?id=2293230 • CWE-416: Use After Free •
CVSS: -EPSS: 0%CPEs: 2EXPL: 0CVE-2021-47594 – mptcp: never allow the PM to close a listener subflow
https://notcve.org/view.php?id=CVE-2021-47594
In the Linux kernel, the following vulnerability has been resolved: mptcp: never allow the PM to close a listener subflow Currently, when deleting an endpoint the netlink PM treverses all the local MPTCP sockets, regardless of their status. If an MPTCP listener socket is bound to the IP matching the delete endpoint, the listener TCP socket will be closed. That is unexpected, the PM should only affect data subflows. Additionally, syzbot was able to trigger a NULL ptr dereference due to the above: general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] CPU: 1 PID: 6550 Comm: syz-executor122 Not tainted 5.16.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__lock_acquire+0xd7d/0x54a0 kernel/locking/lockdep.c:4897 Code: 0f 0e 41 be 01 00 00 00 0f 86 c8 00 00 00 89 05 69 cc 0f 0e e9 bd 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <80> 3c 02 00 0f 85 f3 2f 00 00 48 81 3b 20 75 17 8f 0f 84 52 f3 ff RSP: 0018:ffffc90001f2f818 EFLAGS: 00010016 RAX: dffffc0000000000 RBX: 0000000000000018 RCX: 0000000000000000 RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 000000000000000a R12: 0000000000000000 R13: ffff88801b98d700 R14: 0000000000000000 R15: 0000000000000001 FS: 00007f177cd3d700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f177cd1b268 CR3: 000000001dd55000 CR4: 0000000000350ee0 Call Trace: <TASK> lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 finish_wait+0xc0/0x270 kernel/sched/wait.c:400 inet_csk_wait_for_connect net/ipv4/inet_connection_sock.c:464 [inline] inet_csk_accept+0x7de/0x9d0 net/ipv4/inet_connection_sock.c:497 mptcp_accept+0xe5/0x500 net/mptcp/protocol.c:2865 inet_accept+0xe4/0x7b0 net/ipv4/af_inet.c:739 mptcp_stream_accept+0x2e7/0x10e0 net/mptcp/protocol.c:3345 do_accept+0x382/0x510 net/socket.c:1773 __sys_accept4_file+0x7e/0xe0 net/socket.c:1816 __sys_accept4+0xb0/0x100 net/socket.c:1846 __do_sys_accept net/socket.c:1864 [inline] __se_sys_accept net/socket.c:1861 [inline] __x64_sys_accept+0x71/0xb0 net/socket.c:1861 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f177cd8b8e9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f177cd3d308 EFLAGS: 00000246 ORIG_RAX: 000000000000002b RAX: ffffffffffffffda RBX: 00007f177ce13408 RCX: 00007f177cd8b8e9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f177ce13400 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f177ce1340c R13: 00007f177cde1004 R14: 6d705f706374706d R15: 0000000000022000 </TASK> Fix the issue explicitly skipping MPTCP socket in TCP_LISTEN status. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: mptcp: nunca permitir que el PM cierre un subflujo de escucha Actualmente, al eliminar un endpoint, el PM de netlink atraviesa todos los sockets MPTCP locales, independientemente de su estado. Si un socket de escucha MPTCP está vinculado a la IP que coincide con el endpoint de eliminación, el socket TCP de escucha se cerrará. Esto es inesperado, el PM solo debería afectar los subflujos de datos. Además, syzbot pudo activar una desreferencia de ptr NULL debido a lo anterior: falla de protección general, probablemente para la dirección no canónica 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref en el rango [0x0000000000000018-0x0000000000000001f] CPU: 1 PID: 6550 Comm: syz-executor122 No contaminado 5.16.0-rc4-syzkaller #0 Nombre del hardware: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__lock_acquire+0xd7d/0x54a0 kernel/locking/lockdep.c:4897 Código: 0f 0e 41 be 01 00 00 00 0f 86 c8 00 00 00 89 05 69 cc 0f 0e e9 bd 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <80> 3c 02 00 0f 85 f3 2f 00 00 48 81 3b 20 75 17 8f 0f 84 52 f3 ff RSP: 0018:ffffc90001f2f818 EFLAGS: 00010016 RAX: 00 RBX: 0000000000000018 RCX: 0000000000000000 RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 000000000000000 a R12: 0000000000000000 R13: ffff88801b98d700 R14: 0000000000000000 R15: 0000000000000001 FS: 00007f177cd3d700(0000) GS:ffff8880b9d00000 (0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f177cd1b268 CR3: 000000001dd55000 CR4: 0000000000350ee0 Seguimiento de llamadas: lock_acquire kernel/locking/lockdep.c:5637 [en línea] +0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [en línea] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 Finish_wait+0xc0/0x270 kernel/sched/wait.c:400 inet_csk_wait_for_connect net/ipv4/inet_connection_sock.c:464 [en línea] inet_csk_accept+0x7de/0x9d0 net/ipv4/inet_connection_sock.c:497 mptcp_accept+0xe5/0x500 net/mptcp/protocol.c:2865 inet_accept+0xe4/0x7b0 net/ipv4/af_inet.c:739 e7/0x10e0 net/mptcp/protocol.c:3345 do_accept+0x382/0x510 net/socket.c:1773 __sys_accept4_file+0x7e/0xe0 net/socket.c:1816 __sys_accept4+0xb0/0x100 net/socket.c:1846 __do_sys_accept net/socket. c:1864 [en línea] __se_sys_accept net/socket.c:1861 [en línea] __x64_sys_accept+0x71/0xb0 net/socket.c:1861 do_syscall_x64 arch/x86/entry/common.c:50 [en línea] do_syscall_64+0x35/0xb0 arch /x86/entry/common.c:80 Entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f177cd8b8e9 Código: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 14 00 00 90 48 89 f8 48 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f177cd3d308 EFLAGS: 00000246 ORIG_RAX: 000000000000002b RAX : ffffffffffffffda RBX: 00007f177ce13408 RCX: 00007f177cd8b8e9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f177 ce13400 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f177ce1340c R13: cde1004 R14: 6d705f706374706d R15: 0000000000022000 Arreglar el problema al omitir explícitamente el socket MPTCP en el estado TCP_LISTEN. • https://git.kernel.org/stable/c/740d798e8767d8a449902b1a1bbc70facfce19b5 https://git.kernel.org/stable/c/1456a0004cc54c58adb2501cb0c95dc8b3c83e9e https://git.kernel.org/stable/c/b0cdc5dbcf2ba0d99785da5aabf1b17943805b8a •
CVSS: -EPSS: 0%CPEs: 3EXPL: 0CVE-2021-47593 – mptcp: clear 'kern' flag from fallback sockets
https://notcve.org/view.php?id=CVE-2021-47593
In the Linux kernel, the following vulnerability has been resolved: mptcp: clear 'kern' flag from fallback sockets The mptcp ULP extension relies on sk->sk_sock_kern being set correctly: It prevents setsockopt(fd, IPPROTO_TCP, TCP_ULP, "mptcp", 6); from working for plain tcp sockets (any userspace-exposed socket). But in case of fallback, accept() can return a plain tcp sk. In such case, sk is still tagged as 'kernel' and setsockopt will work. This will crash the kernel, The subflow extension has a NULL ctx->conn mptcp socket: BUG: KASAN: null-ptr-deref in subflow_data_ready+0x181/0x2b0 Call Trace: tcp_data_ready+0xf8/0x370 [..] En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: mptcp: borrar el indicador 'kern' de los sockets de reserva La extensión mptcp ULP depende de que sk->sk_sock_kern esté configurado correctamente: impide que setsockopt(fd, IPPROTO_TCP, TCP_ULP, "mptcp", 6); de funcionar para sockets tcp simples (cualquier socket expuesto al espacio de usuario). Pero en caso de respaldo, aceptar() puede devolver un sk tcp simple. En tal caso, sk todavía está etiquetado como 'kernel' y setsockopt funcionará. Esto bloqueará el kernel. • https://git.kernel.org/stable/c/cf7da0d66cc1a2a19fc5930bb746ffbb2d4cd1be https://git.kernel.org/stable/c/451f1eded7f56e93aaf52eb547ba97742d9c0e97 https://git.kernel.org/stable/c/c26ac0ea3a91c210cf90452e625dc441adf3e549 https://git.kernel.org/stable/c/d6692b3b97bdc165d150f4c1505751a323a80717 •
CVSS: 5.5EPSS: 0%CPEs: 2EXPL: 0CVE-2021-47592 – net: stmmac: fix tc flower deletion for VLAN priority Rx steering
https://notcve.org/view.php?id=CVE-2021-47592
In the Linux kernel, the following vulnerability has been resolved: net: stmmac: fix tc flower deletion for VLAN priority Rx steering To replicate the issue:- 1) Add 1 flower filter for VLAN Priority based frame steering:- $ IFDEVNAME=eth0 $ tc qdisc add dev $IFDEVNAME ingress $ tc qdisc add dev $IFDEVNAME root mqprio num_tc 8 \ map 0 1 2 3 4 5 6 7 0 0 0 0 0 0 0 0 \ queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 hw 0 $ tc filter add dev $IFDEVNAME parent ffff: protocol 802.1Q \ flower vlan_prio 0 hw_tc 0 2) Get the 'pref' id $ tc filter show dev $IFDEVNAME ingress 3) Delete a specific tc flower record (say pref 49151) $ tc filter del dev $IFDEVNAME parent ffff: pref 49151 From dmesg, we will observe kernel NULL pointer ooops [ 197.170464] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 197.171367] #PF: supervisor read access in kernel mode [ 197.171367] #PF: error_code(0x0000) - not-present page [ 197.171367] PGD 0 P4D 0 [ 197.171367] Oops: 0000 [#1] PREEMPT SMP NOPTI <snip> [ 197.171367] RIP: 0010:tc_setup_cls+0x20b/0x4a0 [stmmac] <snip> [ 197.171367] Call Trace: [ 197.171367] <TASK> [ 197.171367] ? __stmmac_disable_all_queues+0xa8/0xe0 [stmmac] [ 197.171367] stmmac_setup_tc_block_cb+0x70/0x110 [stmmac] [ 197.171367] tc_setup_cb_destroy+0xb3/0x180 [ 197.171367] fl_hw_destroy_filter+0x94/0xc0 [cls_flower] The above issue is due to previous incorrect implementation of tc_del_vlan_flow(), shown below, that uses flow_cls_offload_flow_rule() to get struct flow_rule *rule which is no longer valid for tc filter delete operation. struct flow_rule *rule = flow_cls_offload_flow_rule(cls); struct flow_dissector *dissector = rule->match.dissector; So, to ensure tc_del_vlan_flow() deletes the right VLAN cls record for earlier configured RX queue (configured by hw_tc) in tc_add_vlan_flow(), this patch introduces stmmac_rfs_entry as driver-side flow_cls_offload record for 'RX frame steering' tc flower, currently used for VLAN priority. The implementation has taken consideration for future extension to include other type RX frame steering such as EtherType based. v2: - Clean up overly extensive backtrace and rewrite git message to better explain the kernel NULL pointer issue. En el kernel de Linux, se resolvió la siguiente vulnerabilidad: net: stmmac: corrija la eliminación de flores tc para la dirección Rx con prioridad de VLAN Para replicar el problema: - 1) Agregue 1 filtro de flores para la dirección de cuadros basada en prioridad de VLAN: - $ IFDEVNAME=eth0 $ tc qdisc agregar dev $IFDEVNAME ingreso $ tc qdisc agregar dev $IFDEVNAME raíz mqprio num_tc 8 \ map 0 1 2 3 4 5 6 7 0 0 0 0 0 0 0 0 0 \ colas 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 hw 0 $ tc filter add dev $IFDEVNAME parent ffff: protocolo 802.1Q \ flower vlan_prio 0 hw_tc 0 2) Obtener el id 'pref' $ tc filter show dev $IFDEVNAME ingress 3 ) Eliminar un registro de flor tc específico (digamos pref 49151) $ tc filter del dev $IFDEVNAME parent ffff: pref 49151 Desde dmesg, observaremos el puntero NULL del kernel ooops [ 197.170464] ERROR: desreferencia del puntero NULL del kernel, dirección: 00000000000000000 [ 197.171367] #PF: acceso de lectura de supervisor en modo kernel [ 197.171367] #PF: error_code(0x0000) - página no presente [ 197.171367] PGD 0 P4D 0 [ 197.171367] Ups: 0000 [#1] PREEMPT SMP NOPTI [ 197.171367] RIP: 0010:tc_setup_cls+0x20b/0x4a0 [stmmac] [ 197.171367] Seguimiento de llamadas: [ 197.171367] [ 197.171367] ? __stmmac_disable_all_queues+0xa8/0xe0 [stmmac] [ 197.171367] stmmac_setup_tc_block_cb+0x70/0x110 [stmmac] [ 197.171367] tc_setup_cb_destroy+0xb3/0x180 [ 197.171367] destroy_filter+0x94/0xc0 [cls_flower] El problema anterior se debe a una implementación anterior incorrecta de tc_del_vlan_flow( ), que se muestra a continuación, que usa flow_cls_offload_flow_rule() para obtener la estructura flow_rule *rule que ya no es válida para la operación de eliminación del filtro tc. estructura flow_rule *regla = flow_cls_offload_flow_rule(cls); estructura flow_dissector *dissector = regla->match.dissector; Por lo tanto, para garantizar que tc_del_vlan_flow() elimine el registro VLAN cls correcto para la cola RX configurada anteriormente (configurada por hw_tc) en tc_add_vlan_flow(), este parche introduce stmmac_rfs_entry como registro flow_cls_offload del lado del controlador para la flor tc 'Dirección de trama RX', actualmente utilizada para Prioridad de VLAN. • https://git.kernel.org/stable/c/0e039f5cf86ce2fcb62077a163e7ff3d7b7b7cf3 https://git.kernel.org/stable/c/97cb5c82aa1dd85a39b1bd021c8b5f18af623779 https://git.kernel.org/stable/c/aeb7c75cb77478fdbf821628e9c95c4baa9adc63 https://access.redhat.com/security/cve/CVE-2021-47592 https://bugzilla.redhat.com/show_bug.cgi?id=2293235 • CWE-476: NULL Pointer Dereference •