cbcvebase.
CVE-2025-21867
published 2025-03-27

CVE-2025-21867: In the Linux kernel, the following vulnerability has been resolved: bpf, test_run: Fix use-after-free issue in eth_skb_pkt_type() KMSAN reported a…

PriorityP339high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.18%
7.9th percentile
In the Linux kernel, the following vulnerability has been resolved: bpf, test_run: Fix use-after-free issue in eth_skb_pkt_type() KMSAN reported a use-after-free issue in eth_skb_pkt_type()[1]. The cause of the issue was that eth_skb_pkt_type() accessed skb's data that didn't contain an Ethernet header. This occurs when bpf_prog_test_run_xdp() passes an invalid value as the user_data argument to bpf_test_init(). Fix this by returning an error when user_data is less than ETH_HLEN in bpf_test_init(). Additionally, remove the check for "if (user_size > size)" as it is unnecessary. [1] BUG: KMSAN: use-after-free in eth_skb_pkt_type include/linux/etherdevice.h:627 [inline] BUG: KMSAN: use-after-free in eth_type_trans+0x4ee/0x980 net/ethernet/eth.c:165 eth_skb_pkt_type include/linux/etherdevice.h:627 [inline] eth_type_trans+0x4ee/0x980 net/ethernet/eth.c:165 __xdp_build_skb_from_frame+0x5a8/0xa50 net/core/xdp.c:635 xdp_recv_frames net/bpf/test_run.c:272 [inline] xdp_test_run_batch net/bpf/test_run.c:361 [inline] bpf_test_run_xdp_live+0x2954/0x3330 net/bpf/test_run.c:390 bpf_prog_test_run_xdp+0x148e/0x1b10 net/bpf/test_run.c:1318 bpf_prog_test_run+0x5b7/0xa30 kernel/bpf/syscall.c:4371 __sys_bpf+0x6a6/0xe20 kernel/bpf/syscall.c:5777 __do_sys_bpf kernel/bpf/syscall.c:5866 [inline] __se_sys_bpf kernel/bpf/syscall.c:5864 [inline] __x64_sys_bpf+0xa4/0xf0 kernel/bpf/syscall.c:5864 x64_sys_call+0x2ea0/0x3d90 arch/x86/include/generated/asm/syscalls_64.h:322 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd9/0x1d0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Uninit was created at: free_pages_prepare mm/page_alloc.c:1056 [inline] free_unref_page+0x156/0x1320 mm/page_alloc.c:2657 __free_pages+0xa3/0x1b0 mm/page_alloc.c:4838 bpf_ringbuf_free kernel/bpf/ringbuf.c:226 [inline] ringbuf_map_free+0xff/0x1e0 kernel/bpf/ringbuf.c:235 bpf_map_free kernel/bpf/syscall.c:838 [inline] bpf_map_free_deferred+0x17c/0x310 kernel/bpf/syscall.c:862 process

Affected

21 ranges
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>= be3d72a2896cb24090f268dce4aa8a304d40bc23 < f615fccfc689cb48977d275ac2e391297b52392bf615fccfc689cb48977d275ac2e391297b52392b
linuxlinux>= be3d72a2896cb24090f268dce4aa8a304d40bc23 < d56d8a23d95100b65f40438639dd82db2af81c11d56d8a23d95100b65f40438639dd82db2af81c11
linuxlinux>= be3d72a2896cb24090f268dce4aa8a304d40bc23 < 972bafed67ca73ad9a56448384281eb5fd5c0ba3972bafed67ca73ad9a56448384281eb5fd5c0ba3
linuxlinux>= be3d72a2896cb24090f268dce4aa8a304d40bc23 < 1a9e1284e87d59b1303b69d1808d310821d6e5f71a9e1284e87d59b1303b69d1808d310821d6e5f7
linuxlinux>= be3d72a2896cb24090f268dce4aa8a304d40bc23 < 6b3d638ca897e099fa99bd6d02189d3176f80a476b3d638ca897e099fa99bd6d02189d3176f80a47
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
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 < 6.8.0-78.786.8.0-78.78
linuxlinux_kernel>= 5.18 < 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
osv7.8HIGH
vendor_debian7.8HIGH
vendor_msrc7.8HIGH
vendor_redhat7.8HIGH
vendor_ubuntu5.5MEDIUM
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