cbcvebase.
CVE-2026-23273
published 2026-03-20

CVE-2026-23273: In the Linux kernel, the following vulnerability has been resolved: macvlan: observe an RCU grace period in macvlan_common_newlink() error path valis reported…

PriorityP340high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.13%
2.6th percentile
In the Linux kernel, the following vulnerability has been resolved: macvlan: observe an RCU grace period in macvlan_common_newlink() error path valis reported that a race condition still happens after my prior patch. macvlan_common_newlink() might have made @dev visible before detecting an error, and its caller will directly call free_netdev(dev). We must respect an RCU period, either in macvlan or the core networking stack. After adding a temporary mdelay(1000) in macvlan_forward_source_one() to open the race window, valis repro was: ip link add p1 type veth peer p2 ip link set address 00:00:00:00:00:20 dev p1 ip link set up dev p1 ip link set up dev p2 ip link add mv0 link p2 type macvlan mode source (ip link add invalid% link p2 type macvlan mode source macaddr add 00:00:00:00:00:20 &) ; sleep 0.5 ; ping -c1 -I p1 1.2.3.4 PING 1.2.3.4 (1.2.3.4): 56 data bytes RTNETLINK answers: Invalid argument BUG: KASAN: slab-use-after-free in macvlan_forward_source (drivers/net/macvlan.c:408 drivers/net/macvlan.c:444) Read of size 8 at addr ffff888016bb89c0 by task e/175 CPU: 1 UID: 1000 PID: 175 Comm: e Not tainted 6.19.0-rc8+ #33 NONE Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014 Call Trace: dump_stack_lvl (lib/dump_stack.c:123) print_report (mm/kasan/report.c:379 mm/kasan/report.c:482) ? macvlan_forward_source (drivers/net/macvlan.c:408 drivers/net/macvlan.c:444) kasan_report (mm/kasan/report.c:597) ? macvlan_forward_source (drivers/net/macvlan.c:408 drivers/net/macvlan.c:444) macvlan_forward_source (drivers/net/macvlan.c:408 drivers/net/macvlan.c:444) ? tasklet_init (kernel/softirq.c:983) macvlan_handle_frame (drivers/net/macvlan.c:501) Allocated by task 169: kasan_save_stack (mm/kasan/common.c:58) kasan_save_track (./arch/x86/include/asm/current.h:25 mm/kasan/common.c:70 mm/kasan/common.c:79) __kasan_kmalloc (mm/kasan/common.c:419) __kvmalloc_node_noprof (./include/linux/kasan.h:263 mm/slub.c:5657 mm/slub.c:7140) alloc_netdev_m

Affected

71 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.18.14-1 (forky)linux 6.18.14-1 (forky)
linuxlinux
linuxlinux>= 11ba9f0dc865136174cb98834280fb21bbc950c7 < 19c7d8ac51988d053709c1e85bd8482076af845d19c7d8ac51988d053709c1e85bd8482076af845d
linuxlinux>= 5.10.250 < 5.10.2525.10.252
linuxlinux>= 5.15.200 < 5.15.2025.15.202
linuxlinux>= 5dae6b36a7cb7a4fcf4121b95e9ca7f96f816c8a < 3d94323c80d7fc4da5f10f9bb06a45d39d5d3cc43d94323c80d7fc4da5f10f9bb06a45d39d5d3cc4
linuxlinux>= 6.1.163 < 6.1.1656.1.165
linuxlinux>= 6.12.70 < 6.12.756.12.75
linuxlinux>= 6.18.10 < 6.18.146.18.14
linuxlinux>= 6.6.124 < 6.6.1286.6.128
linuxlinux>= 986967a162142710076782d5b93daab93a892980 < a1f686d273d129b45712d95f4095843b864466bda1f686d273d129b45712d95f4095843b864466bd
linuxlinux>= c43d0e787cbba569ec9d11579ed370b50fab6c9c < 721eb342d9ba19bad5c4815ea3921465158b7362721eb342d9ba19bad5c4815ea3921465158b7362
linuxlinux>= cdedcd5aa3f3cb8b7ae0f87ab3a936d0bd583d66 < d34f7a8aa9a25b7e64e0e46e444697c0f702374dd34f7a8aa9a25b7e64e0e46e444697c0f702374d
linuxlinux>= da5c6b8ae47e414be47e5e04def15b25d5c962dc < 91e4ff8d966978901630fc29582c1a76d3c6e46c91e4ff8d966978901630fc29582c1a76d3c6e46c
linuxlinux>= f8db6475a83649689c087a8f52486fcc53e627e9 < 1e58ae87ad1e6e24368dea9aec9048c758cd0e2b1e58ae87ad1e6e24368dea9aec9048c758cd0e2b
linuxlinux>= f8db6475a83649689c087a8f52486fcc53e627e9 < e3f000f0dee1bfab52e2e61ca6a3835d9e187e35e3f000f0dee1bfab52e2e61ca6a3835d9e187e35
linuxlinux_kernel>= 0 < 6.18.14-16.18.14-1
linuxlinux_kernel>= 0 < 5.10.2525.10.252
linuxlinux_kernel>= 5.10.250 < 5.10.2525.10.252
linuxlinux_kernel>= 5.11.0 < 5.15.2025.15.202
linuxlinux_kernel>= 5.15.200 < 5.15.2025.15.202
linuxlinux_kernel>= 5.16.0 < 6.1.1656.1.165
linuxlinux_kernel>= 6.1.163 < 6.1.1656.1.165
linuxlinux_kernel>= 6.12.70 < 6.12.756.12.75
linuxlinux_kernel>= 6.13.0 < 6.18.146.18.14

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_ubuntu9.8CRITICAL
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
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