Description
In the Linux kernel, the following vulnerability has been resolved: staging: fbtft: make dirty_lock IRQ-safe fbtft_mkdirty() can be reached from the fbcon rendering path while processing printk() in hardirq context. Meanwhile, dirty_lock is also taken by fbtft_deferred_io() in workqueue context with local interrupts enabled. Lockdep reports a possible IRQ lock inversion involving dirty_lock and console_owner. A hardirq can interrupt a CPU holding dirty_lock and enter the console rendering path, which can attempt to acquire dirty_lock again. The following lockdep report was observed on an RK3566 system with CONFIG_PROVE_LOCKING enabled: WARNING: possible irq lock inversion dependency detected swapper/2/0 just changed the state of lock: (console_owner){-...}-{0:0} but this lock took another, HARDIRQ-unsafe lock in the past: (&par->dirty_lock){+.+.}-{2:2} CPU0 CPU1 ---- ---- lock(&par->dirty_lock); local_irq_disable(); lock(console_owner); lock(&par->dirty_lock); <Interrupt> lock(console_owner); *** DEADLOCK *** Use spin_lock_irqsave() for fbtft_mkdirty() and spin_lock_irq() for fbtft_deferred_io(). They only access the dirty line range, so the IRQ-off regions remain short.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
c296d5f9957c03994a699d6739c27d4581a9f6c7 to < 0843298b159599ee7bc6d14800efdb4bc7349706affectedc296d5f9957c03994a699d6739c27d4581a9f6c7 to < a323066337ed85c38decfc7f6bbf42f27605dff1affectedc296d5f9957c03994a699d6739c27d4581a9f6c7 to < f2451e18826eb6a33ea51419f39bdd2eb99fa1eaaffectedc296d5f9957c03994a699d6739c27d4581a9f6c7 to < 10cc145b873670438d3b105133dffdae70822db6affectedc296d5f9957c03994a699d6739c27d4581a9f6c7 to < 2a609e29efbba79f9abd68c4ec8a2bd7ecf291e7affectedc296d5f9957c03994a699d6739c27d4581a9f6c7 to < f0c869df2c33793c8828acaab3e4a5e0176f9f00affectedc296d5f9957c03994a699d6739c27d4581a9f6c7 to < dcb48fde8003492256dee45815144aa5ed26ce7caffectedc296d5f9957c03994a699d6739c27d4581a9f6c7 to < f576944a59f31bcffff121117ebf452c5dd162b7affected
Linux Linux
Default version status: affected
4.0affected0 to < 4.0unaffected5.10.271 to ≤ 5.10.*unaffected5.15.222 to ≤ 5.15.*unaffected6.1.189 to ≤ 6.1.*unaffected6.6.158 to ≤ 6.6.*unaffected6.12.111 to ≤ 6.12.*unaffected6.18.53 to ≤ 6.18.*unaffected7.2.7 to ≤ 7.2.*unaffected7.3 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/0843298b159599ee7bc6d14800efdb4bc7349706 ↗
- https://git.kernel.org/stable/c/a323066337ed85c38decfc7f6bbf42f27605dff1 ↗
- https://git.kernel.org/stable/c/f2451e18826eb6a33ea51419f39bdd2eb99fa1ea ↗
- https://git.kernel.org/stable/c/10cc145b873670438d3b105133dffdae70822db6 ↗
- https://git.kernel.org/stable/c/2a609e29efbba79f9abd68c4ec8a2bd7ecf291e7 ↗
- https://git.kernel.org/stable/c/f0c869df2c33793c8828acaab3e4a5e0176f9f00 ↗
- https://git.kernel.org/stable/c/dcb48fde8003492256dee45815144aa5ed26ce7c ↗
- https://git.kernel.org/stable/c/f576944a59f31bcffff121117ebf452c5dd162b7 ↗