Linux Kernel up to 5.15.169/6.1.114/6.6.58/6.11.5 devmap null pointer dereference

Summaryinfo

A vulnerability was found in Linux Kernel up to 5.15.169/6.1.114/6.6.58/6.11.5. It has been rated as problematic. Impacted is an unknown function of the component devmap. The manipulation leads to null pointer dereference. This vulnerability is traded as CVE-2024-50162. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.15.169/6.1.114/6.6.58/6.11.5. It has been rated as problematic. This issue affects an unknown function of the component devmap. The manipulation with an unknown input leads to a null pointer dereference vulnerability. Using CWE to declare the problem leads to CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. Impacted is availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: bpf: devmap: provide rxq after redirect rxq contains a pointer to the device from where the redirect happened. Currently, the BPF program that was executed after a redirect via BPF_MAP_TYPE_DEVMAP* does not have it set. This is particularly bad since accessing ingress_ifindex, e.g. SEC("xdp") int prog(struct xdp_md *pkt) { return bpf_redirect_map(&dev_redirect_map, 0, 0); } SEC("xdp/devmap") int prog_after_redirect(struct xdp_md *pkt) { bpf_printk("ifindex %i", pkt->ingress_ifindex); return XDP_PASS; } depends on access to rxq, so a NULL pointer gets dereferenced: [ 574.475170] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 574.475188] #PF: supervisor read access in kernel mode [ 574.475194] #PF: error_code(0x0000) - not-present page [ 574.475199] PGD 0 P4D 0 [ 574.475207] Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI [ 574.475217] CPU: 4 UID: 0 PID: 217 Comm: kworker/4:1 Not tainted 6.11.0-rc5-reduced-00859-g780801200300 #23 [ 574.475226] Hardware name: Intel(R) Client Systems NUC13ANHi7/NUC13ANBi7, BIOS ANRPL357.0026.2023.0314.1458 03/14/2023 [ 574.475231] Workqueue: mld mld_ifc_work [ 574.475247] RIP: 0010:bpf_prog_5e13354d9cf5018a_prog_after_redirect+0x17/0x3c [ 574.475257] Code: cc cc cc cc cc cc cc 80 00 00 00 cc cc cc cc cc cc cc cc f3 0f 1e fa 0f 1f 44 00 00 66 90 55 48 89 e5 f3 0f 1e fa 48 8b 57 20 8b 52 00 8b 92 e0 00 00 00 48 bf f8 a6 d5 c4 5d a0 ff ff be 0b [ 574.475263] RSP: 0018:ffffa62440280c98 EFLAGS: 00010206 [ 574.475269] RAX: ffffa62440280cd8 RBX: 0000000000000001 RCX: 0000000000000000 [ 574.475274] RDX: 0000000000000000 RSI: ffffa62440549048 RDI: ffffa62440280ce0 [ 574.475278] RBP: ffffa62440280c98 R08: 0000000000000002 R09: 0000000000000001 [ 574.475281] R10: ffffa05dc8b98000 R11: ffffa05f577fca40 R12: ffffa05dcab24000 [ 574.475285] R13: ffffa62440280ce0 R14: ffffa62440549048 R15: ffffa62440549000 [ 574.475289] FS: 0000000000000000(0000) GS:ffffa05f4f700000(0000) knlGS:0000000000000000 [ 574.475294] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 574.475298] CR2: 0000000000000000 CR3: 000000025522e000 CR4: 0000000000f50ef0 [ 574.475303] PKRU: 55555554 [ 574.475306] Call Trace: [ 574.475313] [ 574.475318] ? __die+0x23/0x70 [ 574.475329] ? page_fault_oops+0x180/0x4c0 [ 574.475339] ? skb_pp_cow_data+0x34c/0x490 [ 574.475346] ? kmem_cache_free+0x257/0x280 [ 574.475357] ? exc_page_fault+0x67/0x150 [ 574.475368] ? asm_exc_page_fault+0x26/0x30 [ 574.475381] ? bpf_prog_5e13354d9cf5018a_prog_after_redirect+0x17/0x3c [ 574.475386] bq_xmit_all+0x158/0x420 [ 574.475397] __dev_flush+0x30/0x90 [ 574.475407] veth_poll+0x216/0x250 [veth] [ 574.475421] __napi_poll+0x28/0x1c0 [ 574.475430] net_rx_action+0x32d/0x3a0 [ 574.475441] handle_softirqs+0xcb/0x2c0 [ 574.475451] do_softirq+0x40/0x60 [ 574.475458] [ 574.475461] [ 574.475464] __local_bh_enable_ip+0x66/0x70 [ 574.475471] __dev_queue_xmit+0x268/0xe40 [ 574.475480] ? selinux_ip_postroute+0x213/0x420 [ 574.475491] ? alloc_skb_with_frags+0x4a/0x1d0 [ 574.475502] ip6_finish_output2+0x2be/0x640 [ 574.475512] ? nf_hook_slow+0x42/0xf0 [ 574.475521] ip6_finish_output+0x194/0x300 [ 574.475529] ? __pfx_ip6_finish_output+0x10/0x10 [ 574.475538] mld_sendpack+0x17c/0x240 [ 574.475548] mld_ifc_work+0x192/0x410 [ 574.475557] process_one_work+0x15d/0x380 [ 574.475566] worker_thread+0x29d/0x3a0 [ 574.475573] ? __pfx_worker_thread+0x10/0x10 [ 574.475580] ? __pfx_worker_thread+0x10/0x10 [ 574.475587] kthread+0xcd/0x100 [ 574.475597] ? __pfx_kthread+0x10/0x10 [ 574.475606] ret_from_fork+0x31/0x50 [ 574.475615] ? __pfx_kthread+0x10/0x10 [ 574.475623] ret_from_fork_asm+0x1a/0x ---truncated---

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2024-50162 since 10/21/2024. The exploitation is known to be difficult. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 212918 (CBL Mariner 2.0 Security Update: kernel (CVE-2024-50162)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.15.170, 6.1.115, 6.6.59 or 6.11.6 eliminates this vulnerability. Applying the patch fe068afb8686/a778fbe087c1/49454f09936a/9167d1c274a3/ca9984c5f0ab is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at Tenable (212918). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.15.169
• 6.1.114
• 6.6.0
• 6.6.1
• 6.6.2
• 6.6.3
• 6.6.4
• 6.6.5
• 6.6.6
• 6.6.7
• 6.6.8
• 6.6.9
• 6.6.10
• 6.6.11
• 6.6.12
• 6.6.13
• 6.6.14
• 6.6.15
• 6.6.16
• 6.6.17
• 6.6.18
• 6.6.19
• 6.6.20
• 6.6.21
• 6.6.22
• 6.6.23
• 6.6.24
• 6.6.25
• 6.6.26
• 6.6.27
• 6.6.28
• 6.6.29
• 6.6.30
• 6.6.31
• 6.6.32
• 6.6.33
• 6.6.34
• 6.6.35
• 6.6.36
• 6.6.37
• 6.6.38
• 6.6.39
• 6.6.40
• 6.6.41
• 6.6.42
• 6.6.43
• 6.6.44
• 6.6.45
• 6.6.46
• 6.6.47
• 6.6.48
• 6.6.49
• 6.6.50
• 6.6.51
• 6.6.52
• 6.6.53
• 6.6.54
• 6.6.55
• 6.6.56
• 6.6.57
• 6.6.58
• 6.11.0
• 6.11.1
• 6.11.2
• 6.11.3
• 6.11.4
• 6.11.5

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion