Live › vulnerability › CVE-2026-98922
Go to dashboardThe Linux kernel's emac Ethernet driver set up its netdev operations too late, so a PHY attach during probe dereferenced a NULL pointer and crashed the kernel at driver initialization. The sources describe a crash (denial of service) on affected PowerPC 44x boards, and do not describe code execution.
Summary written from the sources below. Check the originals before acting.
First seen by InfraStack 2026-10-23 21:57 UTC. All times on this page are UTC.
Only systems running Linux kernels from v7.3-rc1 onward that load the emac Ethernet driver, which the sources describe on PowerPC 44x boards such as the WD MyBook Live (RGMII). The crash happens during driver initialization at boot. Teams running x86, ARM or other hardware without the emac driver can skip it.
No product ranges from the sources yet.
uname -rlsmod | grep emac or dmesg | grep -i emacEach row is the first time that source carried this signal. The analyst’s rows are its own findings.
In the Linux kernel, the following vulnerability has been resolved:
net: emac: move setting of netops to fix crash
fixes the following crash on driver initialization:
|BUG: Kernel NULL pointer dereference on read at 0x00000158 |Faulting instruction address: 0xc0566b40 |Oops: Kernel access of bad area, sig: 11 [#1] |BE PAGE_SIZE=4K PowerPC 44x Platform |Modules linked in: |CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Tainted: GW 7.3.0-rc3+ #1 |Tainted: [W]=WARN |Hardware name: MyBook Live APM821XX 0x12c41c83 PowerPC 44x Platform |NIP: c0566b40 LR: c05648f8 CTR: c04c1e9c |REGS: c1053a20 TRAP: 0300 Tainted: GW (7.3.0-rc3+) |MSR: 0002b000 <CE,EE,FP,ME> CR: 24008808 XER: 00000000 |DEAR: 00000158 ESR: 00000000 |GPR00: c05648f8 c1053b10 c1063600 c1030000 c5ab3000 00000000 [...] |GPR08: 00000002 00000000 00000000 c1053b40 84002808 00000000 [...] |GPR16: cfffd210 00000002 c0beafcc cfffc960 00000000 c1030644 [...] |GPR24: c0beafbc c1037000 00000000 0000000a 00000000 c1030000 [...] |NIP [c0566b40] phy_link_topo_add_phy+0x2c/0x1d0 |LR [c05648f8] phy_attach_direct+0x1a4/0x368 |Call Trace: |[c1053b10] [c0811e04] klist_put+0x54/0xb4 (unreliable) |[c1053b40] [c05648f8] phy_attach_direct+0x1a4/0x368 |[c1053b70] [c0564ae8] phy_connect_direct+0x2c/0x60 |[c1053b90] [c056c7a8] of_phy_connect+0x50/0x74 |[c1053bc0] [c0572a88] emac_probe+0xd50/0x119c |[c1053c90] [c04cb770] platform_probe+0x74/0xa4 |[c1053cb0] [c04c8f08] really_probe+0x120/0x2b0 |[c1053cd0] [c04c9254] __driver_probe_device+0x1bc/0x1fc |[c1053d00] [c04c9334] driver_probe_device+0x38/0xa8 |[c1053d30] [c04c9560] __driver_attach+0xf4/0x10c |[c1053d50] [c04c6af8] bus_for_each_dev+0x68/0xd0 |[c1053d90] [c04c7c34] bus_add_driver+0xcc/0x1ec |[c1053dc0] [c04c9f6c] driver_register+0xcc/0x110 |[c1053de0] [c0aa3f40] emac_init+0x1c4/0x200
This bug showed up starting with v7.3-rc1. At the NIP in phy_link_topo_add_phy() is a netdev_need_ops_lock() check. This was added by the following commit ded86da4bbb7 ("net: ethtool: relax ethnl_req_get_phydev() locking assertion")
The bug shows up because at the time of_phy_connect() was called, the netdev_ops were not yet determined. My fix is to move the code that sets netdev_ops+commac.ops+ethtool_ops further up as emac_init_config() derives that by looking at the device-tree and sets the required dev->phy_mode accordingly.
During review, the Sashiko bot's AI stated that the commac assignment became a dead store. Great catch! To keep the original behavior as-is, one mentioned option "set dev->commac.ops = &emac_commac_ops only in the non-gige case?" sounded like a great plan. So the dev->commac.ops assignment for the non-gige-case moves into the else block.
This patch was tested on a WD MyBook Live (RGMII). the device now works again.
This page as .md · .json · in your agent: get_signal("CVE-2026-98922")
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