CVE-2024-26725: dpll: fix possible deadlock during netlink dump operation

Description

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

dpll: fix possible deadlock during netlink dump operation

Recently, I've been hitting following deadlock warning during dpll pin
dump:

[52804.637962] ======================================================
[52804.638536] WARNING: possible circular locking dependency detected
[52804.639111] 6.8.0-rc2jiri+ #1 Not tainted
[52804.639529] ------------------------------------------------------
[52804.640104] python3/2984 is trying to acquire lock:
[52804.640581] ffff88810e642678 (nlk_cb_mutex-GENERIC){+.+.}-{3:3}, at: netlink_dump+0xb3/0x780
[52804.641417]
but task is already holding lock:
[52804.642010] ffffffff83bde4c8 (dpll_lock){+.+.}-{3:3}, at: dpll_lock_dumpit+0x13/0x20
[52804.642747]
which lock already depends on the new lock.

[52804.643551]
the existing dependency chain (in reverse order) is:
[52804.644259]
-> #1 (dpll_lock){+.+.}-{3:3}:
[52804.644836] lock_acquire+0x174/0x3e0
[52804.645271] __mutex_lock+0x119/0x1150
[52804.645723] dpll_lock_dumpit+0x13/0x20
[52804.646169] genl_start+0x266/0x320
[52804.646578] __netlink_dump_start+0x321/0x450
[52804.647056] genl_family_rcv_msg_dumpit+0x155/0x1e0
[52804.647575] genl_rcv_msg+0x1ed/0x3b0
[52804.648001] netlink_rcv_skb+0xdc/0x210
[52804.648440] genl_rcv+0x24/0x40
[52804.648831] netlink_unicast+0x2f1/0x490
[52804.649290] ...

Classification

CVE ID: CVE-2024-26725

Affected Products

Vendor: Linux

Product: Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.04% (probability of being exploited)

EPSS Percentile: 11.48% (scored less or equal to compared to others)

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

References

https://git.kernel.org/stable/c/087739cbd0d0b87b6cec2c0799436ac66e24acc8
https://git.kernel.org/stable/c/53c0441dd2c44ee93fddb5473885fd41e4bc2361

Timeline