UBUNTU-CVE-2024-35839
In the Linux kernel, the following vulnerability has been resolved: netfilter: bridge: replace physindev with physinif in nf_bridge_info An skb can be added to a neigh->arp_queue while waiting for an arp reply. Where original skb's skb->dev can be different to neigh's neigh->dev. For instance in case of bridging dnated skb from one veth to another, the skb would be added to a neigh->arp_queue of the bridge. As skb->dev can be reset back to nf_bridge->physindev and used, and as there is no explicit mechanism that prevents this physindev from been freed under us (for instance neigh_flush_dev doesn't cleanup skbs from different device's neigh queue) we can crash on e.g. this stack: arp_process neigh_update skb = __skb_dequeue(&neigh->arp_queue) neigh_resolve_output(..., skb) ... br_nf_dev_xmit br_nf_pre_routing_finish_bridge_slow skb->dev = nf_bridge->physindev br_handle_frame_finish Let's use plain ifindex instead of net_device link. To peek into the original net_device we will use dev_get_by_index_rcu(). Thus either we get device and are safe to use it or we don't get it and drop skb.
02 / AFFECTED SOFTWARE
Affected packages
7 explicit affected versions
53 explicit affected versions
116 explicit affected versions
89 explicit affected versions
50 explicit affected versions
6 explicit affected versions
12 explicit affected versions
16 explicit affected versions
6 explicit affected versions
100 explicit affected versions
85 explicit affected versions
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76 explicit affected versions
7 explicit affected versions
90 explicit affected versions
7 explicit affected versions
84 explicit affected versions
9 explicit affected versions
85 explicit affected versions
35 explicit affected versions
51 explicit affected versions
50 explicit affected versions
18 explicit affected versions
42 explicit affected versions
118 explicit affected versions
64 explicit affected versions
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13 explicit affected versions
4 explicit affected versions
121 explicit affected versions
23 explicit affected versions
124 explicit affected versions
1 explicit affected versions
21 explicit affected versions
9 explicit affected versions
16 explicit affected versions
10 explicit affected versions
76 explicit affected versions
7 explicit affected versions
12 explicit affected versions
111 explicit affected versions
12 explicit affected versions
10 explicit affected versions
1 explicit affected versions
7 explicit affected versions
104 explicit affected versions
12 explicit affected versions
105 explicit affected versions
12 explicit affected versions
120 explicit affected versions
45 explicit affected versions
10 explicit affected versions
37 explicit affected versions
9 explicit affected versions
10 explicit affected versions
68 explicit affected versions
1 explicit affected versions
26 explicit affected versions
13 explicit affected versions
144 explicit affected versions
37 explicit affected versions
1 explicit affected versions
29 explicit affected versions
111 explicit affected versions
13 explicit affected versions
96 explicit affected versions
1 explicit affected versions
100 explicit affected versions
92 explicit affected versions
55 explicit affected versions
33 explicit affected versions
23 explicit affected versions
60 explicit affected versions
10 explicit affected versions
188 explicit affected versions
11 explicit affected versions
12 explicit affected versions
7 explicit affected versions
12 explicit affected versions
138 explicit affected versions
2 explicit affected versions
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93 explicit affected versions
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10 explicit affected versions
26 explicit affected versions
1 explicit affected versions
69 explicit affected versions
13 explicit affected versions
139 explicit affected versions
78 explicit affected versions
16 explicit affected versions
91 explicit affected versions
116 explicit affected versions
3 explicit affected versions
132 explicit affected versions
93 explicit affected versions
1 explicit affected versions
2 explicit affected versions
51 explicit affected versions
92 explicit affected versions
1 explicit affected versions
12 explicit affected versions
71 explicit affected versions
80 explicit affected versions
27 explicit affected versions
66 explicit affected versions
121 explicit affected versions
1 explicit affected versions
1 explicit affected versions
98 explicit affected versions
8 explicit affected versions
55 explicit affected versions
5 explicit affected versions
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1 explicit affected versions
10 explicit affected versions
9 explicit affected versions
110 explicit affected versions
13 explicit affected versions
72 explicit affected versions
7 explicit affected versions
140 explicit affected versions
94 explicit affected versions
10 explicit affected versions
12 explicit affected versions
39 explicit affected versions
108 explicit affected versions
80 explicit affected versions
56 explicit affected versions
44 explicit affected versions
16 explicit affected versions
3 explicit affected versions
13 explicit affected versions
26 explicit affected versions
45 explicit affected versions
37 explicit affected versions
14 explicit affected versions
38 explicit affected versions
167 explicit affected versions
9 explicit affected versions
11 explicit affected versions
92 explicit affected versions
8 explicit affected versions
7 explicit affected versions
97 explicit affected versions
121 explicit affected versions
4 explicit affected versions
81 explicit affected versions
1 explicit affected versions
1 explicit affected versions
91 explicit affected versions
80 explicit affected versions
79 explicit affected versions
10 explicit affected versions
43 explicit affected versions
77 explicit affected versions
119 explicit affected versions
10 explicit affected versions
8 explicit affected versions
88 explicit affected versions
14 explicit affected versions
4 explicit affected versions
78 explicit affected versions
7 explicit affected versions
1 explicit affected versions
69 explicit affected versions
123 explicit affected versions
80 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
In the Linux kernel, the following vulnerability has been resolved: netfilter: bridge: replace physindev with physinif in nf_bridge_info An skb can be added to a neigh->arp_queue while waiting for an arp reply. Where original skb's skb->dev can be different to neigh's neigh->dev. For instance in case of bridging dnated skb from one veth to another, the skb would be added to a neigh->arp_queue of the bridge. As skb->dev can be reset back to nf_bridge->physindev and used, and as there is no explicit mechanism that prevents this physindev from been freed under us (for instance neigh_flush_dev doesn't cleanup skbs from different device's neigh queue) we can crash on e.g. this stack: arp_process neigh_update skb = __skb_dequeue(&neigh->arp_queue) neigh_resolve_output(..., skb) ... br_nf_dev_xmit br_nf_pre_routing_finish_bridge_slow skb->dev = nf_bridge->physindev br_handle_frame_finish Let's use plain ifindex instead of net_device link. To peek into the original net_device we will use dev_get_by_index_rcu(). Thus either we get device and are safe to use it or we don't get it and drop skb.
05 / REFERENCES
Further evidence
- https://git.kernel.org/linus/9874808878d9eed407e3977fd11fee49de1e1d86
- https://git.kernel.org/stable/c/544add1f1cfb78c3dfa3e6edcf4668f6be5e730c
- https://git.kernel.org/stable/c/7ae19ee81ca56b13c50a78de6c47d5b8fdc9d97b
- https://git.kernel.org/stable/c/9325e3188a9cf3f69fc6f32af59844bbc5b90547
- https://git.kernel.org/stable/c/9874808878d9eed407e3977fd11fee49de1e1d86
- https://ubuntu.com/security/CVE-2024-35839
- https://ubuntu.com/security/notices/USN-6818-1
- https://ubuntu.com/security/notices/USN-6818-2
- https://ubuntu.com/security/notices/USN-6818-3
- https://ubuntu.com/security/notices/USN-6818-4
- https://ubuntu.com/security/notices/USN-6819-1
- https://ubuntu.com/security/notices/USN-6819-2
- https://ubuntu.com/security/notices/USN-6819-3
- https://ubuntu.com/security/notices/USN-6819-4
- https://www.cve.org/CVERecord?id=CVE-2024-35839