cbcvebase.
CVE-2025-21858
published 2025-03-12

CVE-2025-21858: In the Linux kernel, the following vulnerability has been resolved: geneve: Fix use-after-free in geneve_find_dev(). syzkaller reported a use-after-free in…

PriorityP339high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.23%
14.3th percentile
In the Linux kernel, the following vulnerability has been resolved: geneve: Fix use-after-free in geneve_find_dev(). syzkaller reported a use-after-free in geneve_find_dev() [0] without repro. geneve_configure() links struct geneve_dev.next to net_generic(net, geneve_net_id)->geneve_list. The net here could differ from dev_net(dev) if IFLA_NET_NS_PID, IFLA_NET_NS_FD, or IFLA_TARGET_NETNSID is set. When dev_net(dev) is dismantled, geneve_exit_batch_rtnl() finally calls unregister_netdevice_queue() for each dev in the netns, and later the dev is freed. However, its geneve_dev.next is still linked to the backend UDP socket netns. Then, use-after-free will occur when another geneve dev is created in the netns. Let's call geneve_dellink() instead in geneve_destroy_tunnels(). [0]: BUG: KASAN: slab-use-after-free in geneve_find_dev drivers/net/geneve.c:1295 [inline] BUG: KASAN: slab-use-after-free in geneve_configure+0x234/0x858 drivers/net/geneve.c:1343 Read of size 2 at addr ffff000054d6ee24 by task syz.1.4029/13441 CPU: 1 UID: 0 PID: 13441 Comm: syz.1.4029 Not tainted 6.13.0-g0ad9617c78ac #24 dc35ca22c79fb82e8e7bc5c9c9adafea898b1e3d Hardware name: linux,dummy-virt (DT) Call trace: show_stack+0x38/0x50 arch/arm64/kernel/stacktrace.c:466 (C) __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0xbc/0x108 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x16c/0x6f0 mm/kasan/report.c:489 kasan_report+0xc0/0x120 mm/kasan/report.c:602 __asan_report_load2_noabort+0x20/0x30 mm/kasan/report_generic.c:379 geneve_find_dev drivers/net/geneve.c:1295 [inline] geneve_configure+0x234/0x858 drivers/net/geneve.c:1343 geneve_newlink+0xb8/0x128 drivers/net/geneve.c:1634 rtnl_newlink_create+0x23c/0x868 net/core/rtnetlink.c:3795 __rtnl_newlink net/core/rtnetlink.c:3906 [inline] rtnl_newlink+0x1054/0x1630 net/core/rtnetlink.c:4021 rtnetlink_rcv_msg+0x61c/0x918 net/core/rtnetlink.c:6911 netlink_rcv_skb+0x1dc/0x398 net/netlink/af_netlink.c

Affected

27 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.133-1 (bookworm)linux 6.1.133-1 (bookworm)
debianlinux-6.1< linux 6.1.133-1 (bookworm)linux 6.1.133-1 (bookworm)
linuxlinux
linuxlinux>= 2d07dc79fe04a43d82a346ced6bbf07bdb523f1b < d5e86e27de0936f3cb0a299ce519d993e9cf3886d5e86e27de0936f3cb0a299ce519d993e9cf3886
linuxlinux>= 2d07dc79fe04a43d82a346ced6bbf07bdb523f1b < 5a0538ac6826807d6919f6aecbb8996c2865af2c5a0538ac6826807d6919f6aecbb8996c2865af2c
linuxlinux>= 2d07dc79fe04a43d82a346ced6bbf07bdb523f1b < f74f6560146714241c6e167b03165ee77a86e316f74f6560146714241c6e167b03165ee77a86e316
linuxlinux>= 2d07dc79fe04a43d82a346ced6bbf07bdb523f1b < 904e746b2e7fa952ab8801b303ce826a63153d78904e746b2e7fa952ab8801b303ce826a63153d78
linuxlinux>= 2d07dc79fe04a43d82a346ced6bbf07bdb523f1b < 3ce92ca990cfac88a87c61df3cc0b5880e688ecf3ce92ca990cfac88a87c61df3cc0b5880e688ecf
linuxlinux>= 2d07dc79fe04a43d82a346ced6bbf07bdb523f1b < da9b0ae47f084014b1e4b3f31f70a0defd047ff3da9b0ae47f084014b1e4b3f31f70a0defd047ff3
linuxlinux>= 2d07dc79fe04a43d82a346ced6bbf07bdb523f1b < 788dbca056a8783ec063da3c9d49a3a71c76c283788dbca056a8783ec063da3c9d49a3a71c76c283
linuxlinux>= 2d07dc79fe04a43d82a346ced6bbf07bdb523f1b < 9593172d93b9f91c362baec4643003dc298029299593172d93b9f91c362baec4643003dc29802929
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.237-15.10.237-1
linuxlinux_kernel>= 0 < 6.1.133-16.1.133-1
linuxlinux_kernel>= 0 < 6.12.17-16.12.17-1
linuxlinux_kernel>= 0 < 6.12.17-16.12.17-1
linuxlinux_kernel>= 0 < 5.4.0-216.2365.4.0-216.236
linuxlinux_kernel>= 0 < 5.15.0-140.1505.15.0-140.150
linuxlinux_kernel>= 0 < 6.8.0-78.786.8.0-78.78
linuxlinux_kernel>= 4.2 < 6.1.1306.1.130
linuxlinux_kernel>= 6.13 < 6.13.56.13.5
linuxlinux_kernel>= 6.2 < 6.6.806.6.80
linuxlinux_kernel>= 6.7 < 6.12.176.12.17
msrcazl3_kernel_6.6.78.1-3_on_azure_linux_3.0
msrcazl3_kernel_6.6.82.1-1_on_azure_linux_3.0

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv8.8HIGH
vendor_ubuntu8.8HIGH
vendor_debian7.8HIGH
vendor_msrc7.8HIGH
vendor_redhat7.8HIGH
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