CVE-2025-38123
CriticalCVSS 9.8Exploitation Probability (EPSS)
Low risk32th percentile - higher than 32% of all known CVEs
Summary
In the Linux kernel t7xx WWAN driver, a NAPI RX poll issue occurs: after network interface disconnection (dellink), the netdev is freed but still used during skb processing in polling, causing a kernel panic (NULL pointer dereference).
Risk Assessment
An attacker could trigger a kernel panic by initiating a disconnect operation during ongoing NAPI polling, leading to network service disruption and potential data loss.
Recommendation
Apply the Linux kernel patch that adds a netdev validity check before use in the t7xx_ccmni_recv_skb function during NAPI polling.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: net: wwan: t7xx: Fix napi rx poll issue When driver handles the napi rx polling requests, the netdev might have been released by the dellink logic triggered by the disconnect operation on user plane. However, in the logic of processing skb in polling, an invalid netdev is still being used, which causes a panic. BUG: kernel NULL pointer dereference, address: 00000000000000f1 Oops: 0000 [#1] PREEMPT SMP NOPTI RIP: 0010:dev_gro_receive+0x3a/0x620 [...] Call Trace: <IRQ> ? __die_body+0x68/0xb0 ? page_fault_oops+0x379/0x3e0 ? exc_page_fault+0x4f/0xa0 ? asm_exc_page_fault+0x22/0x30 ? __pfx_t7xx_ccmni_recv_skb+0x10/0x10 [mtk_t7xx (HASH:1400 7)] ? dev_gro_receive+0x3a/0x620 napi_gro_receive+0xad/0x170 t7xx_ccmni_recv_skb+0x48/0x70 [mtk_t7xx (HASH:1400 7)] t7xx_dpmaif_napi_rx_poll+0x590/0x800 [mtk_t7xx (HASH:1400 7)] net_rx_action+0x103/0x470 irq_exit_rcu+0x13a/0x310 sysvec_apic_timer_interrupt+0x56/0x90 </IRQ>