Уязвимость функции map_write() ("kernel/user_namespace.c") ядра операционной системы Linux, позволяющая нарушителю получить доступ к конфиденциальным данным, нарушить их целостность, а также вызвать отказ в обслуживании

Уязвимость функции vcpu_scan_ioapic ядра операционной системы Linux, позволяющая нарушителю вызвать отказ в обслуживании

Уязвимость функции crypto_report_one() ядра операционной системы Linux, позволяющая нарушителю получить несанкционированный доступ к защищаемой информации

Уязвимость буфера сокета SCTP ядра операционной системы Linux, позволяющая нарушителю вызвать отказ в обслуживании

Уязвимость функции cdrom_ioctl_select_disc (drivers/cdrom/cdrom.c) ядра операционной системы Linux, позволяющая нарушителю получить доступ к конфиденциальным данным

Уязвимость компонента TCP Pace Handler функции tcp_internal_pacing в файле net/ipv4/tcp_output.c ядра операционной системы Linux, позволяющая нарушителю вызвать отказ в обслуживании

Уязвимость функции qdisc_pkt_len_init() модуля net/core/dev.c ядра операционной системы Linux, позволяющая нарушителю вызвать отказ в обслуживании

Уязвимость компонента ocfs2 ядра операционной системы Linux, позволяющая нарушителю вызвать отказ в обслуживании

An issue was discovered in the Linux kernel through 4.19. An information leak in cdrom_ioctl_select_disc in drivers/cdrom/cdrom.c could be used by local attackers to read kernel memory because a cast from unsigned long to int interferes with bounds checking. This is similar to CVE-2018-10940 and CVE-2018-16658.

In the Linux kernel 4.15.x through 4.19.x before 4.19.2, map_write() in kernel/user_namespace.c allows privilege escalation because it mishandles nested user namespaces with more than 5 UID or GID ranges. A user who has CAP_SYS_ADMIN in an affected user namespace can bypass access controls on resources outside the namespace, as demonstrated by reading /etc/shadow. This occurs because an ID transformation takes place properly for the namespaced-to-kernel direction but not for the kernel-to-namespaced direction.

kvm_pv_send_ipi in arch/x86/kvm/lapic.c in the Linux kernel through 4.19.2 allows local users to cause a denial of service (NULL pointer dereference and BUG) via crafted system calls that reach a situation where the apic map is uninitialized.

The vcpu_scan_ioapic function in arch/x86/kvm/x86.c in the Linux kernel through 4.19.2 allows local users to cause a denial of service (NULL pointer dereference and BUG) via crafted system calls that reach a situation where ioapic is uninitialized.

An issue was discovered in the Linux kernel before 4.19.3. crypto_report_one() and related functions in crypto/crypto_user.c (the crypto user configuration API) do not fully initialize structures that are copied to userspace, potentially leaking sensitive memory to user programs. NOTE: this is a CVE-2013-2547 regression but with easier exploitability because the attacker does not need a capability (however, the system must have the CONFIG_CRYPTO_USER kconfig option).

The SCTP socket buffer used by a userspace application is not accounted by the cgroups subsystem. An attacker can use this flaw to cause a denial of service attack. Kernel 3.10.x and 4.18.x branches are believed to be vulnerable.

An issue was discovered in the Linux Kernel from 4.18 to 4.19, an improper update of sock reference in TCP pacing can lead to memory/netns leak, which can be used by remote clients.

In the Linux kernel, the following vulnerability has been resolved: net: avoid potential underflow in qdisc_pkt_len_init() with UFO After commit 7c6d2ecbda83 ("net: be more gentle about silly gso requests coming from user") virtio_net_hdr_to_skb() had sanity check to detect malicious attempts from user space to cook a bad GSO packet. Then commit cf9acc90c80ec ("net: virtio_net_hdr_to_skb: count transport header in UFO") while fixing one issue, allowed user space to cook a GSO packet with the following characteristic : IPv4 SKB_GSO_UDP, gso_size=3, skb->len = 28. When this packet arrives in qdisc_pkt_len_init(), we end up with hdr_len = 28 (IPv4 header + UDP header), matching skb->len Then the following sets gso_segs to 0 : gso_segs = DIV_ROUND_UP(skb->len - hdr_len, shinfo->gso_size); Then later we set qdisc_skb_cb(skb)->pkt_len to back to zero :/ qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len; This leads to the following crash in fq_codel [1] qdisc_pkt_len_init() is best effort, we only want an estimation of the bytes sent on the wire, not crashing the kernel. This patch is fixing this particular issue, a following one adds more sanity checks for another potential bug. [1] [ 70.724101] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 70.724561] #PF: supervisor read access in kernel mode [ 70.724561] #PF: error_code(0x0000) - not-present page [ 70.724561] PGD 10ac61067 P4D 10ac61067 PUD 107ee2067 PMD 0 [ 70.724561] Oops: Oops: 0000 [#1] SMP NOPTI [ 70.724561] CPU: 11 UID: 0 PID: 2163 Comm: b358537762 Not tainted 6.11.0-virtme #991 [ 70.724561] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 70.724561] RIP: 0010:fq_codel_enqueue (net/sched/sch_fq_codel.c:120 net/sched/sch_fq_codel.c:168 net/sched/sch_fq_codel.c:230) sch_fq_codel [ 70.724561] Code: 24 08 49 c1 e1 06 44 89 7c 24 18 45 31 ed 45 31 c0 31 ff 89 44 24 14 4c 03 8b 90 01 00 00 eb 04 39 ca 73 37 4d 8b 39 83 c7 01 <49> 8b 17 49 89 11 41 8b 57 28 45 8b 5f 34 49 c7 07 00 00 00 00 49 All code ======== 0: 24 08 and $0x8,%al 2: 49 c1 e1 06 shl $0x6,%r9 6: 44 89 7c 24 18 mov %r15d,0x18(%rsp) b: 45 31 ed xor %r13d,%r13d e: 45 31 c0 xor %r8d,%r8d 11: 31 ff xor %edi,%edi 13: 89 44 24 14 mov %eax,0x14(%rsp) 17: 4c 03 8b 90 01 00 00 add 0x190(%rbx),%r9 1e: eb 04 jmp 0x24 20: 39 ca cmp %ecx,%edx 22: 73 37 jae 0x5b 24: 4d 8b 39 mov (%r9),%r15 27: 83 c7 01 add $0x1,%edi 2a:* 49 8b 17 mov (%r15),%rdx <-- trapping instruction 2d: 49 89 11 mov %rdx,(%r9) 30: 41 8b 57 28 mov 0x28(%r15),%edx 34: 45 8b 5f 34 mov 0x34(%r15),%r11d 38: 49 c7 07 00 00 00 00 movq $0x0,(%r15) 3f: 49 rex.WB Code starting with the faulting instruction =========================================== 0: 49 8b 17 mov (%r15),%rdx 3: 49 89 11 mov %rdx,(%r9) 6: 41 8b 57 28 mov 0x28(%r15),%edx a: 45 8b 5f 34 mov 0x34(%r15),%r11d e: 49 c7 07 00 00 00 00 movq $0x0,(%r15) 15: 49 rex.WB [ 70.724561] RSP: 0018:ffff95ae85e6fb90 EFLAGS: 00000202 [ 70.724561] RAX: 0000000002000000 RBX: ffff95ae841de000 RCX: 0000000000000000 [ 70.724561] RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 [ 70.724561] RBP: ffff95ae85e6fbf8 R08: 0000000000000000 R09: ffff95b710a30000 [ 70.724561] R10: 0000000000000000 R11: bdf289445ce31881 R12: ffff95ae85e6fc58 [ 70.724561] R13: 0000000000000000 R14: 0000000000000040 R15: 0000000000000000 [ 70.724561] FS: 000000002c5c1380(0000) GS:ffff95bd7fcc0000(0000) knlGS:0000000000000000 [ 70.724561] CS: 0010 DS: 0000 ES: 0000 C ---truncated---

In the Linux kernel, the following vulnerability has been resolved: ocfs2: remove unreasonable unlock in ocfs2_read_blocks Patch series "Misc fixes for ocfs2_read_blocks", v5. This series contains 2 fixes for ocfs2_read_blocks(). The first patch fix the issue reported by syzbot, which detects bad unlock balance in ocfs2_read_blocks(). The second patch fixes an issue reported by Heming Zhao when reviewing above fix. This patch (of 2): There was a lock release before exiting, so remove the unreasonable unlock.