GHSA-MF99-5486-2JH2
Vulnerability from github – Published: 2026-05-08 15:31 – Updated: 2026-05-11 09:30In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: RX, Fix XDP multi-buf frag counting for legacy RQ
XDP multi-buf programs can modify the layout of the XDP buffer when the program calls bpf_xdp_pull_data() or bpf_xdp_adjust_tail(). The referenced commit in the fixes tag corrected the assumption in the mlx5 driver that the XDP buffer layout doesn't change during a program execution. However, this fix introduced another issue: the dropped fragments still need to be counted on the driver side to avoid page fragment reference counting issues.
Such issue can be observed with the test_xdp_native_adjst_tail_shrnk_data selftest when using a payload of 3600 and shrinking by 256 bytes (an upcoming selftest patch): the last fragment gets released by the XDP code but doesn't get tracked by the driver. This results in a negative pp_ref_count during page release and the following splat:
WARNING: include/net/page_pool/helpers.h:297 at mlx5e_page_release_fragmented.isra.0+0x4a/0x50 [mlx5_core], CPU#12: ip/3137 Modules linked in: [...] CPU: 12 UID: 0 PID: 3137 Comm: ip Not tainted 6.19.0-rc3+ #12 NONE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 RIP: 0010:mlx5e_page_release_fragmented.isra.0+0x4a/0x50 [mlx5_core] [...] Call Trace: mlx5e_dealloc_rx_wqe+0xcb/0x1a0 [mlx5_core] mlx5e_free_rx_descs+0x7f/0x110 [mlx5_core] mlx5e_close_rq+0x50/0x60 [mlx5_core] mlx5e_close_queues+0x36/0x2c0 [mlx5_core] mlx5e_close_channel+0x1c/0x50 [mlx5_core] mlx5e_close_channels+0x45/0x80 [mlx5_core] mlx5e_safe_switch_params+0x1a5/0x230 [mlx5_core] mlx5e_change_mtu+0xf3/0x2f0 [mlx5_core] netif_set_mtu_ext+0xf1/0x230 do_setlink.isra.0+0x219/0x1180 rtnl_newlink+0x79f/0xb60 rtnetlink_rcv_msg+0x213/0x3a0 netlink_rcv_skb+0x48/0xf0 netlink_unicast+0x24a/0x350 netlink_sendmsg+0x1ee/0x410 __sock_sendmsg+0x38/0x60 _syssendmsg+0x232/0x280 _sys_sendmsg+0x78/0xb0 __sys_sendmsg+0x5f/0xb0 [...] do_syscall_64+0x57/0xc50
This patch fixes the issue by doing page frag counting on all the original XDP buffer fragments for all relevant XDP actions (XDP_TX , XDP_REDIRECT and XDP_PASS). This is basically reverting to the original counting before the commit in the fixes tag.
As frag_page is still pointing to the original tail, the nr_frags parameter to xdp_update_skb_frags_info() needs to be calculated in a different way to reflect the new nr_frags.
{
"affected": [],
"aliases": [
"CVE-2026-43464"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-05-08T15:16:59Z",
"severity": "HIGH"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/mlx5e: RX, Fix XDP multi-buf frag counting for legacy RQ\n\nXDP multi-buf programs can modify the layout of the XDP buffer when the\nprogram calls bpf_xdp_pull_data() or bpf_xdp_adjust_tail(). The\nreferenced commit in the fixes tag corrected the assumption in the mlx5\ndriver that the XDP buffer layout doesn\u0027t change during a program\nexecution. However, this fix introduced another issue: the dropped\nfragments still need to be counted on the driver side to avoid page\nfragment reference counting issues.\n\nSuch issue can be observed with the\ntest_xdp_native_adjst_tail_shrnk_data selftest when using a payload of\n3600 and shrinking by 256 bytes (an upcoming selftest patch): the last\nfragment gets released by the XDP code but doesn\u0027t get tracked by the\ndriver. This results in a negative pp_ref_count during page release and\nthe following splat:\n\n WARNING: include/net/page_pool/helpers.h:297 at mlx5e_page_release_fragmented.isra.0+0x4a/0x50 [mlx5_core], CPU#12: ip/3137\n Modules linked in: [...]\n CPU: 12 UID: 0 PID: 3137 Comm: ip Not tainted 6.19.0-rc3+ #12 NONE\n Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014\n RIP: 0010:mlx5e_page_release_fragmented.isra.0+0x4a/0x50 [mlx5_core]\n [...]\n Call Trace:\n \u003cTASK\u003e\n mlx5e_dealloc_rx_wqe+0xcb/0x1a0 [mlx5_core]\n mlx5e_free_rx_descs+0x7f/0x110 [mlx5_core]\n mlx5e_close_rq+0x50/0x60 [mlx5_core]\n mlx5e_close_queues+0x36/0x2c0 [mlx5_core]\n mlx5e_close_channel+0x1c/0x50 [mlx5_core]\n mlx5e_close_channels+0x45/0x80 [mlx5_core]\n mlx5e_safe_switch_params+0x1a5/0x230 [mlx5_core]\n mlx5e_change_mtu+0xf3/0x2f0 [mlx5_core]\n netif_set_mtu_ext+0xf1/0x230\n do_setlink.isra.0+0x219/0x1180\n rtnl_newlink+0x79f/0xb60\n rtnetlink_rcv_msg+0x213/0x3a0\n netlink_rcv_skb+0x48/0xf0\n netlink_unicast+0x24a/0x350\n netlink_sendmsg+0x1ee/0x410\n __sock_sendmsg+0x38/0x60\n ____sys_sendmsg+0x232/0x280\n ___sys_sendmsg+0x78/0xb0\n __sys_sendmsg+0x5f/0xb0\n [...]\n do_syscall_64+0x57/0xc50\n\nThis patch fixes the issue by doing page frag counting on all the\noriginal XDP buffer fragments for all relevant XDP actions (XDP_TX ,\nXDP_REDIRECT and XDP_PASS). This is basically reverting to the original\ncounting before the commit in the fixes tag.\n\nAs frag_page is still pointing to the original tail, the nr_frags\nparameter to xdp_update_skb_frags_info() needs to be calculated\nin a different way to reflect the new nr_frags.",
"id": "GHSA-mf99-5486-2jh2",
"modified": "2026-05-11T09:30:32Z",
"published": "2026-05-08T15:31:29Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-43464"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/03cb50e5b74fce8bf6d92b860371b66253cf0f8d"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/a6413e6f6c9d9bb9833324cb3753582f7bc0f2fa"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/c74557495efb4bd0adefdfc8678ecdbc82a06da3"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
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