Debian: CVE-2024-40957: linux, linux-6.1 -- security update

Debian: CVE-2024-40957: linux, linux-6.1 -- security update

Severity

5

CVSS

(AV:L/AC:L/Au:S/C:N/I:N/A:C)

Published

07/12/2024

Created

07/19/2024

Added

07/18/2024

Modified

01/28/2025

Description

In the Linux kernel, the following vulnerability has been resolved: seg6: fix parameter passing when calling NF_HOOK() in End.DX4 and End.DX6 behaviors input_action_end_dx4() and input_action_end_dx6() are called NF_HOOK() for PREROUTING hook, in PREROUTING hook, we should passing a valid indev, and a NULL outdev to NF_HOOK(), otherwise may trigger a NULL pointer dereference, as below: [74830.647293] BUG: kernel NULL pointer dereference, address: 0000000000000090 [74830.655633] #PF: supervisor read access in kernel mode [74830.657888] #PF: error_code(0x0000) - not-present page [74830.659500] PGD 0 P4D 0 [74830.660450] Oops: 0000 [#1] PREEMPT SMP PTI ... [74830.664953] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 [74830.666569] RIP: 0010:rpfilter_mt+0x44/0x15e [ipt_rpfilter] ... [74830.689725] Call Trace: [74830.690402]<IRQ> [74830.690953]? show_trace_log_lvl+0x1c4/0x2df [74830.692020]? show_trace_log_lvl+0x1c4/0x2df [74830.693095]? ipt_do_table+0x286/0x710 [ip_tables] [74830.694275]? __die_body.cold+0x8/0xd [74830.695205]? page_fault_oops+0xac/0x140 [74830.696244]? exc_page_fault+0x62/0x150 [74830.697225]? asm_exc_page_fault+0x22/0x30 [74830.698344]? rpfilter_mt+0x44/0x15e [ipt_rpfilter] [74830.699540]ipt_do_table+0x286/0x710 [ip_tables] [74830.700758]? ip6_route_input+0x19d/0x240 [74830.701752]nf_hook_slow+0x3f/0xb0 [74830.702678]input_action_end_dx4+0x19b/0x1e0 [74830.703735]? input_action_end_t+0xe0/0xe0 [74830.704734]seg6_local_input_core+0x2d/0x60 [74830.705782]lwtunnel_input+0x5b/0xb0 [74830.706690]__netif_receive_skb_one_core+0x63/0xa0 [74830.707825]process_backlog+0x99/0x140 [74830.709538]__napi_poll+0x2c/0x160 [74830.710673]net_rx_action+0x296/0x350 [74830.711860]__do_softirq+0xcb/0x2ac [74830.713049]do_softirq+0x63/0x90 input_action_end_dx4() passing a NULL indev to NF_HOOK(), and finally trigger a NULL dereference in rpfilter_mt()->rpfilter_is_loopback(): static bool rpfilter_is_loopback(const struct sk_buff *skb, const struct net_device *in) { // in is NULL return skb->pkt_type == PACKET_LOOPBACK || in->flags & IFF_LOOPBACK; }

Solution(s)

• debian-upgrade-linux
• debian-upgrade-linux-6-1

References

• https://attackerkb.com/topics/cve-2024-40957
• CVE - 2024-40957
• DSA-5731-1