Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
net/bnx2x: Prevent access to a freed page in page_pool
Fix race condition leading to system crash during EEH error handling
During EEH error recovery, the bnx2x driver’s transmit timeout logic could cause a race condition when handling reset tasks. The bnx2x_tx_timeout() schedules reset tasks via bnx2x_sp_rtnl_task(), which ultimately leads to bnx2x_nic_unload(). In bnx2x_nic_unload() SGEs are freed using bnx2x_free_rx_sge_range(). However, this could overlap with the EEH driver’s attempt to reset the device using bnx2x_io_slot_reset(), which also tries to free SGEs. This race condition can result in system crashes due to accessing freed memory locations in bnx2x_free_rx_sge()
799 static inline void bnx2x_free_rx_sge(struct bnx2x *bp, 800 struct bnx2x_fastpath *fp, u16 index) 801 { 802 struct sw_rx_page *sw_buf = &fp->rx_page_ring[index]; 803 struct page *page = sw_buf->page; …. where sw_buf was set to NULL after the call to dma_unmap_page() by the preceding thread.
EEH: Beginning: ‘slot_reset’ PCI 0011:01:00.0#10000: EEH: Invoking bnx2x->slot_reset() bnx2x: [bnx2x_io_slot_reset:14228(eth1)]IO slot reset initializing… bnx2x 0011:01:00.0: enabling device (0140 -> 0142) bnx2x: [bnx2x_io_slot_reset:14244(eth1)]IO slot reset –> driver unload Kernel attempted to read user page (0) - exploit attempt? (uid: 0) BUG: Kernel NULL pointer dereference on read at 0x00000000 Faulting instruction address: 0xc0080000025065fc Oops: Kernel access of bad area, sig: 11 [#1] ….. Call Trace: [c000000003c67a20] [c00800000250658c] bnx2x_io_slot_reset+0x204/0x610 [bnx2x] (unreliable) [c000000003c67af0] [c0000000000518a8] eeh_report_reset+0xb8/0xf0 [c000000003c67b60] [c000000000052130] eeh_pe_report+0x180/0x550 [c000000003c67c70] [c00000000005318c] eeh_handle_normal_event+0x84c/0xa60 [c000000003c67d50] [c000000000053a84] eeh_event_handler+0xf4/0x170 [c000000003c67da0] [c000000000194c58] kthread+0x1c8/0x1d0 [c000000003c67e10] [c00000000000cf64] ret_from_kernel_thread+0x5c/0x64
To solve this issue, we need to verify page pool allocations before freeing.
Details
- Affected product:
- AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , CentOS 6 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , CloudLinux 6 ELS , Debian 10 ELS , Oracle Linux 6 ELS , Oracle Linux 7 ELS , TuxCare 9.6 ESU , TuxCare 9.8 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
- Affected packages:
- kernel @ 5.10.0 (+17 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| AlmaLinux 8 | Released |
42 kernels
|
| Amazon Linux 2 | Released |
81 kernels
|
| Amazon Linux 2 5.10 | Will Not Fix | — |
| Amazon Linux 2 5.4 | Released |
45 kernels
|
| CentOS 8 | Released |
33 kernels
|
| CloudLinux OS 7h | Released |
57 kernels
|
| CloudLinux OS 8 | Released |
53 kernels
|
| Debian 10 | Will Not Fix | — |
| Debian 10 cloud | Will Not Fix | — |
| Debian 11 | Released |
28 kernels
|
| Debian 11 cloud | Released |
8 kernels
|
| Oracle Linux 6 UEK 4 | Planned | — |
| Oracle Linux 7 UEK 4 | Planned | — |
| Oracle Linux 8 | Released |
66 kernels
|
| Proxmox VE 7 5.15 | Released |
44 kernels
|
| RHEL 8 | Released |
63 kernels
|
| Rocky Linux 8 | Released |
36 kernels
|
| Ubuntu 20.04 | Planned | — |
| Ubuntu 20.04 AWS | Will Not Fix | — |
| Ubuntu 20.04 Azure | Planned | — |
| Ubuntu 20.04 GCP | Planned | — |
| Ubuntu 20.04 HWE AWS | Released |
39 kernels
|
| Ubuntu 20.04 HWE Azure | Released |
23 kernels
|
| Ubuntu 22.04 | Released |
52 kernels
|
| Ubuntu 22.04 AWS | Released |
46 kernels
|
| Ubuntu 22.04 Azure | Released |
43 kernels
|
| Ubuntu 24.04 | Released |
1 kernel
|