CVE-2024-35934

In the Linux kernel, the following vulnerability has been resolved: net/smc: reduce rtnl pressure in smc_pnet_create_pnetids_list() Many syzbot reports show extreme rtnl pressure, and many of them hint that smc acquires rtnl in netns creation for no good reason [1] This patch returns early from smc_pnet_net_init() if there is no netdevice yet. I am not even sure why smc_pnet_create_pnetids_list() even exists, because smc_pnet_netdev_event() is also calling smc_pnet_add_base_pnetid() when handling NETDEV_UP event. [1] extract of typical syzbot reports 2 locks held by syz-executor.3/12252: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 locks held by syz-executor.4/12253: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 locks held by syz-executor.1/12257: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 locks held by syz-executor.2/12261: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 locks held by syz-executor.0/12265: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 locks held by syz-executor.3/12268: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 locks held by syz-executor.4/12271: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 locks held by syz-executor.1/12274: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 locks held by syz-executor.2/12280: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878
Configurations

Configuration 1 (hide)

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

Configuration 2 (hide)

cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

History

17 Dec 2025, 03:40

Type Values Removed Values Added
First Time Linux
Debian
Debian debian Linux
Linux linux Kernel
CWE NVD-CWE-noinfo
CPE cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
References () https://git.kernel.org/stable/c/00af2aa93b76b1bade471ad0d0525d4d29ca5cc0 - () https://git.kernel.org/stable/c/00af2aa93b76b1bade471ad0d0525d4d29ca5cc0 - Patch
References () https://git.kernel.org/stable/c/6e920422e7104928f760fc0e12b6d65ab097a2e7 - () https://git.kernel.org/stable/c/6e920422e7104928f760fc0e12b6d65ab097a2e7 - Patch
References () https://git.kernel.org/stable/c/a2e6bffc0388526ed10406040279a693d62b36ec - () https://git.kernel.org/stable/c/a2e6bffc0388526ed10406040279a693d62b36ec - Patch
References () https://git.kernel.org/stable/c/b9117dc783c0ab0a3866812f70e07bf2ea071ac4 - () https://git.kernel.org/stable/c/b9117dc783c0ab0a3866812f70e07bf2ea071ac4 - Patch
References () https://git.kernel.org/stable/c/bc4d1ebca11b4f194e262326bd45938e857c59d2 - () https://git.kernel.org/stable/c/bc4d1ebca11b4f194e262326bd45938e857c59d2 - Patch
References () https://git.kernel.org/stable/c/d7ee3bf0caf599c14db0bf4af7aacd6206ef8a23 - () https://git.kernel.org/stable/c/d7ee3bf0caf599c14db0bf4af7aacd6206ef8a23 - Patch
References () https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html - () https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html - Third Party Advisory, Mailing List
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 5.5

21 Nov 2024, 09:21

Type Values Removed Values Added
References
  • () https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html -
References () https://git.kernel.org/stable/c/00af2aa93b76b1bade471ad0d0525d4d29ca5cc0 - () https://git.kernel.org/stable/c/00af2aa93b76b1bade471ad0d0525d4d29ca5cc0 -
References () https://git.kernel.org/stable/c/6e920422e7104928f760fc0e12b6d65ab097a2e7 - () https://git.kernel.org/stable/c/6e920422e7104928f760fc0e12b6d65ab097a2e7 -
References () https://git.kernel.org/stable/c/a2e6bffc0388526ed10406040279a693d62b36ec - () https://git.kernel.org/stable/c/a2e6bffc0388526ed10406040279a693d62b36ec -
References () https://git.kernel.org/stable/c/b9117dc783c0ab0a3866812f70e07bf2ea071ac4 - () https://git.kernel.org/stable/c/b9117dc783c0ab0a3866812f70e07bf2ea071ac4 -
References () https://git.kernel.org/stable/c/bc4d1ebca11b4f194e262326bd45938e857c59d2 - () https://git.kernel.org/stable/c/bc4d1ebca11b4f194e262326bd45938e857c59d2 -
References () https://git.kernel.org/stable/c/d7ee3bf0caf599c14db0bf4af7aacd6206ef8a23 - () https://git.kernel.org/stable/c/d7ee3bf0caf599c14db0bf4af7aacd6206ef8a23 -

05 Nov 2024, 10:16

Type Values Removed Values Added
References
  • {'url': 'https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html', 'source': '416baaa9-dc9f-4396-8d5f-8c081fb06d67'}

25 Jun 2024, 22:15

Type Values Removed Values Added
References
  • () https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html -
Summary
  • (es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net/smc: reduce la presión rtnl en smc_pnet_create_pnetids_list() Muchos informes de syzbot muestran una presión rtnl extrema, y muchos de ellos insinúan que smc adquiere rtnl en la creación de netns sin una buena razón [1] Este parche regresa temprano desde smc_pnet_net_init() si aún no hay un netdevice. Ni siquiera estoy seguro de por qué existe smc_pnet_create_pnetids_list(), porque smc_pnet_netdev_event() también llama a smc_pnet_add_base_pnetid() cuando maneja el evento NETDEV_UP. [1] extracto de informes típicos de syzbot 2 bloqueos mantenidos por syz-executor.3/12252: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, en: copy_net_ns+0x4c7/0x7b0 net/core /net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, en: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [en línea] #1: ffffffff8f375b88 (rtnl_mutex){+ .+.}-{3:3}, en: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 bloqueos retenidos por syz-executor.4/12253: #0: ffffffff8f369610 (pernet_ops_rwsem){+++ +}-{3:3}, en: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, en: smc_pnet_create_pnetids_list net/ smc/smc_pnet.c:809 [en línea] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, en: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 bloqueos retenidos por syz-executor.1/12257: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, en: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex ){+.+.}-{3:3}, en: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [en línea] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, en : smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 bloqueos retenidos por syz-executor.2/12261: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, en: copy_net_ns +0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, en: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [en línea] #1 : ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, en: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 bloqueos retenidos por syz-executor.0/12265: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, en: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3 }, en: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [en línea] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, en: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet. c:878 2 bloqueos retenidos por syz-executor.3/12268: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, en: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c: 491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, en: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [en línea] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}- {3:3}, en: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 bloqueos retenidos por syz-executor.4/12271: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3 :3}, en: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, en: smc_pnet_create_pnetids_list net/smc/smc_pnet.c :809 [en línea] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, en: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 bloqueos retenidos por syz-executor.1 /12274: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, en: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+ .}-{3:3}, en: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [en línea] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, en: smc_pnet_net_init+0x10a/ 0x1e0 net/smc/smc_pnet.c:878 2 bloqueos retenidos por syz-executor.2/12280: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, en: copy_net_ns+0x4c7/0x7b0 net /core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, en: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [en línea] #1: ffffffff8f375b88 (rtnl_mutex) {+.+.}-{3:3}, en: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878

19 May 2024, 11:15

Type Values Removed Values Added
New CVE

Information

Published : 2024-05-19 11:15

Updated : 2025-12-17 03:40


NVD link : CVE-2024-35934

Mitre link : CVE-2024-35934

CVE.ORG link : CVE-2024-35934


JSON object : View

Products Affected

debian

  • debian_linux

linux

  • linux_kernel