CVE-2021-47162
published 2024-03-25CVE-2021-47162: In the Linux kernel, the following vulnerability has been resolved: tipc: skb_linearize the head skb when reassembling msgs It's not a good idea to append the…
PriorityP421medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.74%
51.0th percentile
In the Linux kernel, the following vulnerability has been resolved:
tipc: skb_linearize the head skb when reassembling msgs
It's not a good idea to append the frag skb to a skb's frag_list if
the frag_list already has skbs from elsewhere, such as this skb was
created by pskb_copy() where the frag_list was cloned (all the skbs
in it were skb_get'ed) and shared by multiple skbs.
However, the new appended frag skb should have been only seen by the
current skb. Otherwise, it will cause use after free crashes as this
appended frag skb are seen by multiple skbs but it only got skb_get
called once.
The same thing happens with a skb updated by pskb_may_pull() with a
skb_cloned skb. Li Shuang has reported quite a few crashes caused
by this when doing testing over macvlan devices:
[] kernel BUG at net/core/skbuff.c:1970!
[] Call Trace:
[] skb_clone+0x4d/0xb0
[] macvlan_broadcast+0xd8/0x160 [macvlan]
[] macvlan_process_broadcast+0x148/0x150 [macvlan]
[] process_one_work+0x1a7/0x360
[] worker_thread+0x30/0x390
[] kernel BUG at mm/usercopy.c:102!
[] Call Trace:
[] __check_heap_object+0xd3/0x100
[] __check_object_size+0xff/0x16b
[] simple_copy_to_iter+0x1c/0x30
[] __skb_datagram_iter+0x7d/0x310
[] __skb_datagram_iter+0x2a5/0x310
[] skb_copy_datagram_iter+0x3b/0x90
[] tipc_recvmsg+0x14a/0x3a0 [tipc]
[] ____sys_recvmsg+0x91/0x150
[] ___sys_recvmsg+0x7b/0xc0
[] kernel BUG at mm/slub.c:305!
[] Call Trace:
[]
[] kmem_cache_free+0x3ff/0x400
[] __netif_receive_skb_core+0x12c/0xc40
[] ? kmem_cache_alloc+0x12e/0x270
[] netif_receive_skb_internal+0x3d/0xb0
[] ? get_rx_page_info+0x8e/0xa0 [be2net]
[] be_poll+0x6ef/0xd00 [be2net]
[] ? irq_exit+0x4f/0x100
[] net_rx_action+0x149/0x3b0
...
This patch is to fix it by linearizing the head skb if it has frag_list
set in tipc_buf_append(). Note that we choose to do this before calling
skb_unshare(), as __skb_linearize() will avoid skb_copy(). Also, we can
not just drop the frag_list either as the early time.
Affected
28 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 5.14.6-1 (bookworm) | linux 5.14.6-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | — | — |
| linux | linux | — | — |
| linux | linux | >= 4.1.14 < 4.2 | 4.2 |
| linux | linux | >= 4.2.7 < 4.3 | 4.3 |
| linux | linux | >= 45c8b7b175ceb2d542e0fe15247377bf3bce29ec < b2c8d28c34b3070407cb1741f9ba3f15d0284b8b | b2c8d28c34b3070407cb1741f9ba3f15d0284b8b |
| linux | linux | >= 45c8b7b175ceb2d542e0fe15247377bf3bce29ec < 5489f30bb78ff0dafb4229a69632afc2ba20765c | 5489f30bb78ff0dafb4229a69632afc2ba20765c |
| linux | linux | >= 45c8b7b175ceb2d542e0fe15247377bf3bce29ec < 436d650d374329a591c30339a91fa5078052ed1e | 436d650d374329a591c30339a91fa5078052ed1e |
| linux | linux | >= 45c8b7b175ceb2d542e0fe15247377bf3bce29ec < 4b1761898861117c97066aea6c58f68a7787f0bf | 4b1761898861117c97066aea6c58f68a7787f0bf |
| linux | linux | >= 45c8b7b175ceb2d542e0fe15247377bf3bce29ec < 64d17ec9f1ded042c4b188d15734f33486ed9966 | 64d17ec9f1ded042c4b188d15734f33486ed9966 |
| linux | linux | >= 45c8b7b175ceb2d542e0fe15247377bf3bce29ec < 6da24cfc83ba4f97ea44fc7ae9999a006101755c | 6da24cfc83ba4f97ea44fc7ae9999a006101755c |
| linux | linux | >= 45c8b7b175ceb2d542e0fe15247377bf3bce29ec < ace300eecbccaa698e2b472843c74a5f33f7dce8 | ace300eecbccaa698e2b472843c74a5f33f7dce8 |
| linux | linux | >= 45c8b7b175ceb2d542e0fe15247377bf3bce29ec < b7df21cf1b79ab7026f545e7bf837bd5750ac026 | b7df21cf1b79ab7026f545e7bf837bd5750ac026 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 5.10.46-1 | 5.10.46-1 |
| linux | linux_kernel | >= 0 < 5.14.6-1 | 5.14.6-1 |
| linux | linux_kernel | >= 0 < 5.14.6-1 | 5.14.6-1 |
| linux | linux_kernel | >= 0 < 5.14.6-1 | 5.14.6-1 |
| linux | linux_kernel | >= 4.10 < 4.14.235 | 4.14.235 |
| linux | linux_kernel | >= 4.15 < 4.19.193 | 4.19.193 |
| linux | linux_kernel | >= 4.20 < 5.4.124 | 5.4.124 |
| linux | linux_kernel | >= 4.3 < 4.4.271 | 4.4.271 |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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Red Hat
kernel: tipc: skb_linearize the head skb when reassembling msgs
vendor_redhat·2024-03-25·CVSS 5.5
CVE-2021-47162 [MEDIUM] CWE-416 kernel: tipc: skb_linearize the head skb when reassembling msgs
kernel: tipc: skb_linearize the head skb when reassembling msgs
In the Linux kernel, the following vulnerability has been resolved:
tipc: skb_linearize the head skb when reassembling msgs
It's not a good idea to append the frag skb to a skb's frag_list if
the frag_list already has skbs from elsewhere, such as this skb was
created by pskb_copy() where the frag_list was cloned (all the skbs
in it were skb_get'ed) and shared by multiple skbs.
However, the new appended frag skb should have been only seen by the
current skb. Otherwise, it will cause use after free crashes as this
appended frag skb are seen by multiple skbs but it only got skb_get
called once.
The same thing happens with a skb updated by pskb_may_pull() with a
skb_cloned skb. Li Shuang has reported quite a few crashes caused
by
Debian
CVE-2021-47162: linux - In the Linux kernel, the following vulnerability has been resolved: tipc: skb_l...
vendor_debian·2021·CVSS 5.5
CVE-2021-47162 [MEDIUM] CVE-2021-47162: linux - In the Linux kernel, the following vulnerability has been resolved: tipc: skb_l...
In the Linux kernel, the following vulnerability has been resolved: tipc: skb_linearize the head skb when reassembling msgs It's not a good idea to append the frag skb to a skb's frag_list if the frag_list already has skbs from elsewhere, such as this skb was created by pskb_copy() where the frag_list was cloned (all the skbs in it were skb_get'ed) and shared by multiple skbs. However, the new appended frag skb should have been only seen by the current skb. Otherwise, it will cause use after free crashes as this appended frag skb are seen by multiple skbs but it only got skb_get called once. The same thing happens with a skb updated by pskb_may_pull() with a skb_cloned skb. Li Shuang has reported quite a few crashes caused by this when doing testing over macvlan devices: [] kernel BUG at n
VulDB
Linux Kernel up to 5.12.8 net/core/skbuff.c pskb_copy use after free (WID-SEC-2024-0699)
vuldb·2026-08-05·CVSS 5.5
CVE-2021-47162 [MEDIUM] Linux Kernel up to 5.12.8 net/core/skbuff.c pskb_copy use after free (WID-SEC-2024-0699)
A vulnerability was found in Linux Kernel up to 5.12.8. It has been rated as critical. This affects the function pskb_copy of the file net/core/skbuff.c. The manipulation leads to use after free.
This vulnerability is documented as CVE-2021-47162. The attack requires being on the local network. There is not any exploit available.
Upgrading the affected component is advised.
GHSA
GHSA-86fr-x2qv-cxp5: In the Linux kernel, the following vulnerability has been resolved:
tipc: skb_linearize the head skb when reassembling msgs
It's not a good idea to
ghsa_unreviewed·2024-03-25
CVE-2021-47162 [MEDIUM] CWE-416 GHSA-86fr-x2qv-cxp5: In the Linux kernel, the following vulnerability has been resolved:
tipc: skb_linearize the head skb when reassembling msgs
It's not a good idea to
In the Linux kernel, the following vulnerability has been resolved:
tipc: skb_linearize the head skb when reassembling msgs
It's not a good idea to append the frag skb to a skb's frag_list if
the frag_list already has skbs from elsewhere, such as this skb was
created by pskb_copy() where the frag_list was cloned (all the skbs
in it were skb_get'ed) and shared by multiple skbs.
However, the new appended frag skb should have been only seen by the
current skb. Otherwise, it will cause use after free crashes as this
appended frag skb are seen by multiple skbs but it only got skb_get
called once.
The same thing happens with a skb updated by pskb_may_pull() with a
skb_cloned skb. Li Shuang has reported quite a few crashes caused
by this when doing testing over macvlan devices:
[] kernel BUG
OSV
CVE-2021-47162: In the Linux kernel, the following vulnerability has been resolved: tipc: skb_linearize the head skb when reassembling msgs It's not a good idea to ap
osv·2024-03-25·CVSS 5.5
CVE-2021-47162 [MEDIUM] CVE-2021-47162: In the Linux kernel, the following vulnerability has been resolved: tipc: skb_linearize the head skb when reassembling msgs It's not a good idea to ap
In the Linux kernel, the following vulnerability has been resolved: tipc: skb_linearize the head skb when reassembling msgs It's not a good idea to append the frag skb to a skb's frag_list if the frag_list already has skbs from elsewhere, such as this skb was created by pskb_copy() where the frag_list was cloned (all the skbs in it were skb_get'ed) and shared by multiple skbs. However, the new appended frag skb should have been only seen by the current skb. Otherwise, it will cause use after free crashes as this appended frag skb are seen by multiple skbs but it only got skb_get called once. The same thing happens with a skb updated by pskb_may_pull() with a skb_cloned skb. Li Shuang has reported quite a few crashes caused by this when doing testing over macvlan devices: [] kernel BUG at n
No detection rules found.
No public exploits indexed.
https://git.kernel.org/stable/c/436d650d374329a591c30339a91fa5078052ed1ehttps://git.kernel.org/stable/c/4b1761898861117c97066aea6c58f68a7787f0bfhttps://git.kernel.org/stable/c/5489f30bb78ff0dafb4229a69632afc2ba20765chttps://git.kernel.org/stable/c/64d17ec9f1ded042c4b188d15734f33486ed9966https://git.kernel.org/stable/c/6da24cfc83ba4f97ea44fc7ae9999a006101755chttps://git.kernel.org/stable/c/ace300eecbccaa698e2b472843c74a5f33f7dce8https://git.kernel.org/stable/c/b2c8d28c34b3070407cb1741f9ba3f15d0284b8bhttps://git.kernel.org/stable/c/b7df21cf1b79ab7026f545e7bf837bd5750ac026https://git.kernel.org/stable/c/436d650d374329a591c30339a91fa5078052ed1ehttps://git.kernel.org/stable/c/4b1761898861117c97066aea6c58f68a7787f0bfhttps://git.kernel.org/stable/c/5489f30bb78ff0dafb4229a69632afc2ba20765chttps://git.kernel.org/stable/c/64d17ec9f1ded042c4b188d15734f33486ed9966https://git.kernel.org/stable/c/6da24cfc83ba4f97ea44fc7ae9999a006101755chttps://git.kernel.org/stable/c/ace300eecbccaa698e2b472843c74a5f33f7dce8https://git.kernel.org/stable/c/b2c8d28c34b3070407cb1741f9ba3f15d0284b8bhttps://git.kernel.org/stable/c/b7df21cf1b79ab7026f545e7bf837bd5750ac026
2024-03-25
Published