CVE-2026-46287

In the Linux kernel, the following vulnerability has been resolved:

net: txgbe: fix RTNL assertion warning when remove module

For the copper NIC with external PHY, the driver called phylink_connect_phy() during probe and phylink_disconnect_phy() during remove. It caused an RTNL assertion warning in phylink_disconnect_phy() upon module remove.

To fix this, add rtnl_lock() and rtnl_unlock() around the phylink_disconnect_phy() in remove function.

————[ cut here ]———— RTNL: assertion failed at drivers/net/phy/phylink.c (2351) WARNING: drivers/net/phy/phylink.c:2351 at phylink_disconnect_phy+0xd8/0xf0 [phylink], CPU#0: rmmod/4464 Modules linked in: … CPU: 0 UID: 0 PID: 4464 Comm: rmmod Kdump: loaded Not tainted 7.0.0-rc4+ Hardware name: Micro-Star International Co., Ltd. MS-7E16/X670E GAMING PLUS WIFI (MS-7E16), BIOS 1.90 12/31/2024 RIP: 0010:phylink_disconnect_phy+0xe4/0xf0 [phylink] Code: 5b 41 5c 41 5d 41 5e 41 5f 5d 31 c0 31 d2 31 f6 31 ff e9 3a 38 8f e7 48 8d 3d 48 87 e2 ff ba 2f 09 00 00 48 c7 c6 c1 22 24 c0 <67> 48 0f b9 3a e9 34 ff ff ff 66 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffce7288363ac0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff89654b2a1a00 RCX: 0000000000000000 RDX: 000000000000092f RSI: ffffffffc02422c1 RDI: ffffffffc0239020 RBP: ffffce7288363ae8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8964c4022000 R13: ffff89654fce3028 R14: ffff89654ebb4000 R15: ffffffffc0226348 FS: 0000795e80d93780(0000) GS:ffff896c52857000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005b528b592000 CR3: 0000000170d0f000 CR4: 0000000000f50ef0 PKRU: 55555554 Call Trace: txgbe_remove_phy+0xbb/0xd0 [txgbe] txgbe_remove+0x4c/0xb0 [txgbe] pci_device_remove+0x41/0xb0 device_remove+0x43/0x80 device_release_driver_internal+0x206/0x270 driver_detach+0x4a/0xa0 bus_remove_driver+0x83/0x120 driver_unregister+0x2f/0x60 pci_unregister_driver+0x40/0x90 txgbe_driver_exit+0x10/0x850 [txgbe] __do_sys_delete_module.isra.0+0x1c3/0x2f0 __x64_sys_delete_module+0x12/0x20 x64_sys_call+0x20c3/0x2390 do_syscall_64+0x11c/0x1500 ? srso_alias_return_thunk+0x5/0xfbef5 ? do_syscall_64+0x15a/0x1500 ? srso_alias_return_thunk+0x5/0xfbef5 ? do_fault+0x312/0x580 ? srso_alias_return_thunk+0x5/0xfbef5 ? __handle_mm_fault+0x9d5/0x1040 ? srso_alias_return_thunk+0x5/0xfbef5 ? count_memcg_events+0x101/0x1d0 ? srso_alias_return_thunk+0x5/0xfbef5 ? handle_mm_fault+0x1e8/0x2f0 ? srso_alias_return_thunk+0x5/0xfbef5 ? do_user_addr_fault+0x2f8/0x820 ? srso_alias_return_thunk+0x5/0xfbef5 ? irqentry_exit+0xb2/0x600 ? srso_alias_return_thunk+0x5/0xfbef5 ? exc_page_fault+0x92/0x1c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Weakness

The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.

Affected Software

Extended Description

While assertion is good for catching logic errors and reducing the chances of reaching more serious vulnerability conditions, it can still lead to a denial of service. For example, if a server handles multiple simultaneous connections, and an assert() occurs in one single connection that causes all other connections to be dropped, this is a reachable assertion that leads to a denial of service.

Potential Mitigations

References

• https://git.kernel.org/stable/c/0305e7118451c7c363c18f8113b0d8e0077ffa4c
• https://git.kernel.org/stable/c/3e223a7fd41ce6fffdb10577df9350385262bf33
• https://git.kernel.org/stable/c/6c5ec52c68a6a442c8a159615ae092512562318a
• https://git.kernel.org/stable/c/d29cafc7e4ee9e28a150ba17e9a565ec5d881fbc
• https://git.kernel.org/stable/c/e159f05e12cc1111a3103b99375ddf0dfd0e7d63