{"id":"AZL-60302","summary":"CVE-2025-21961 affecting package kernel 6.6.126.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\neth: bnxt: fix truesize for mb-xdp-pass case\n\nWhen mb-xdp is set and return is XDP_PASS, packet is converted from\nxdp_buff to sk_buff with xdp_update_skb_shared_info() in\nbnxt_xdp_build_skb().\nbnxt_xdp_build_skb() passes incorrect truesize argument to\nxdp_update_skb_shared_info().\nThe truesize is calculated as BNXT_RX_PAGE_SIZE * sinfo-\u003enr_frags but\nthe skb_shared_info was wiped by napi_build_skb() before.\nSo it stores sinfo-\u003enr_frags before bnxt_xdp_build_skb() and use it\ninstead of getting skb_shared_info from xdp_get_shared_info_from_buff().\n\nSplat looks like:\n ------------[ cut here ]------------\n WARNING: CPU: 2 PID: 0 at net/core/skbuff.c:6072 skb_try_coalesce+0x504/0x590\n Modules linked in: xt_nat xt_tcpudp veth af_packet xt_conntrack nft_chain_nat xt_MASQUERADE nf_conntrack_netlink xfrm_user xt_addrtype nft_coms\n CPU: 2 UID: 0 PID: 0 Comm: swapper/2 Not tainted 6.14.0-rc2+ #3\n RIP: 0010:skb_try_coalesce+0x504/0x590\n Code: 4b fd ff ff 49 8b 34 24 40 80 e6 40 0f 84 3d fd ff ff 49 8b 74 24 48 40 f6 c6 01 0f 84 2e fd ff ff 48 8d 4e ff e9 25 fd ff ff \u003c0f\u003e 0b e99\n RSP: 0018:ffffb62c4120caa8 EFLAGS: 00010287\n RAX: 0000000000000003 RBX: ffffb62c4120cb14 RCX: 0000000000000ec0\n RDX: 0000000000001000 RSI: ffffa06e5d7dc000 RDI: 0000000000000003\n RBP: ffffa06e5d7ddec0 R08: ffffa06e6120a800 R09: ffffa06e7a119900\n R10: 0000000000002310 R11: ffffa06e5d7dcec0 R12: ffffe4360575f740\n R13: ffffe43600000000 R14: 0000000000000002 R15: 0000000000000002\n FS:  0000000000000000(0000) GS:ffffa0755f700000(0000) knlGS:0000000000000000\n CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 00007f147b76b0f8 CR3: 00000001615d4000 CR4: 00000000007506f0\n PKRU: 55555554\n Call Trace:\n  \u003cIRQ\u003e\n  ? __warn+0x84/0x130\n  ? skb_try_coalesce+0x504/0x590\n  ? report_bug+0x18a/0x1a0\n  ? handle_bug+0x53/0x90\n  ? exc_invalid_op+0x14/0x70\n  ? asm_exc_invalid_op+0x16/0x20\n  ? skb_try_coalesce+0x504/0x590\n  inet_frag_reasm_finish+0x11f/0x2e0\n  ip_defrag+0x37a/0x900\n  ip_local_deliver+0x51/0x120\n  ip_sublist_rcv_finish+0x64/0x70\n  ip_sublist_rcv+0x179/0x210\n  ip_list_rcv+0xf9/0x130\n\nHow to reproduce:\n\u003cNode A\u003e\nip link set $interface1 xdp obj xdp_pass.o\nip link set $interface1 mtu 9000 up\nip a a 10.0.0.1/24 dev $interface1\n\u003cNode B\u003e\nip link set $interfac2 mtu 9000 up\nip a a 10.0.0.2/24 dev $interface2\nping 10.0.0.1 -s 65000\n\nFollowing ping.py patch adds xdp-mb-pass case. so ping.py is going to be\nable to reproduce this issue.","modified":"2026-04-01T05:19:36.707175Z","published":"2025-04-01T16:15:27Z","upstream":["CVE-2025-21961"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-21961"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"6.6.126.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-60302.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}