CVE-2024-26859: net/bnx2x: Prevent access to a freed page in page_pool

Description

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 0x0000000...

Classification

CVE ID: CVE-2024-26859

Affected Products

Vendor: Linux

Product: Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.04% (probability of being exploited)

EPSS Percentile: 15.26% (scored less or equal to compared to others)

EPSS Date: 2025-02-04 (when was this score calculated)

References

Timeline

2024-12-20 00:34:32 UTC
CVE

net/bnx2x: Prevent access to a freed page in page_pool