Описание
Security update for the Linux Kernel (Live Patch 42 for SUSE Linux Enterprise 15 SP5)
This update for the SUSE Linux Enterprise Kernel 5.14.21-150500.55.172 fixes various security issues:
The following security issues were fixed:
- CVE-2026-43038: ipv6: icmp: clear skb2->cb[] in ip6_err_gen_icmpv6_unreach() (bsc#1271648).
- CVE-2026-53359: KVM: x86: Fix shadow paging use-after-free due to unexpected role (bsc#1270060).
Список пакетов
SUSE Linux Enterprise Live Patching 15 SP4
SUSE Linux Enterprise Live Patching 15 SP5
Ссылки
- Link for SUSE-SU-2026:3350-1
- E-Mail link for SUSE-SU-2026:3350-1
- SUSE Security Ratings
- SUSE Bug 1270060
- SUSE Bug 1271648
- SUSE CVE CVE-2026-43038 page
- SUSE CVE CVE-2026-53359 page
Описание
In the Linux kernel, the following vulnerability has been resolved: ipv6: icmp: clear skb2->cb[] in ip6_err_gen_icmpv6_unreach() Sashiko AI-review observed: In ip6_err_gen_icmpv6_unreach(), the skb is an outer IPv4 ICMP error packet where its cb contains an IPv4 inet_skb_parm. When skb is cloned into skb2 and passed to icmp6_send(), it uses IP6CB(skb2). IP6CB interprets the IPv4 inet_skb_parm as an inet6_skb_parm. The cipso offset in inet_skb_parm.opt directly overlaps with dsthao in inet6_skb_parm at offset 18. If an attacker sends a forged ICMPv4 error with a CIPSO IP option, dsthao would be a non-zero offset. Inside icmp6_send(), mip6_addr_swap() is called and uses ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO). This would scan the inner, attacker-controlled IPv6 packet starting at that offset, potentially returning a fake TLV without checking if the remaining packet length can hold the full 18-byte struct ipv6_destopt_hao. Could mip6_addr_swap() then perform a 16-byte swap that extends past the end of the packet data into skb_shared_info? Should the cb array also be cleared in ip6_err_gen_icmpv6_unreach() and ip6ip6_err() to prevent this? This patch implements the first suggestion. I am not sure if ip6ip6_err() needs to be changed. A separate patch would be better anyway.
Затронутые продукты
Ссылки
- CVE-2026-43038
- SUSE Bug 1264097
- SUSE Bug 1271648
Описание
In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Fix shadow paging use-after-free due to unexpected role Commit 0cb2af2ea66ad ("KVM: x86: Fix shadow paging use-after-free due to unexpected GFN") fixed a shadow paging mismatch between stored and computed GFNs; the bug could be triggered by changing a PDE mapping from outside the guest, and then deleting a memslot. The rmap_remove() call would miss entries created after the PDE change because the GFN of the leaf SPTE does not match the GFN of the struct kvm_mmu_page. A similar hole however remains if the modified PDE points to a non-leaf page. In this case the gfn can be made to match, but the role does not match: the original large 2MB page creates a kvm_mmu_page with direct=1, while the new 4KB needs a kvm_mmu_page with direct=0. However, kvm_mmu_get_child_sp() does not compare the role, and therefore reuses the page. The next step is installing a leaf (4KB) SPTE on the new path which records an rmap entry under the gfn resolved by the walk. But when that child is zapped its parent kvm_mmu_page has direct=1 and kvm_mmu_page_get_gfn() computes the gfn for the 4KB page as sp->gfn + index instead of using sp->shadowed_translation[] (or sp->gfns[] in older kernels). It therefore fails to remove the recorded entry. When the memslot is dropped the shadow page is freed but the rmap entry survives, as in the scenario that was already fixed. Code that later walks that gfn (dirty logging, MMU notifier invalidation, and so on) dereferences an sptep that lies in the freed page, causing the use-after-free.
Затронутые продукты
Ссылки
- CVE-2026-53359
- SUSE Bug 1270059
- SUSE Bug 1270060
- SUSE Bug 1271478