On Wed, 18 Aug 2021 22:05:18 +1000, Michael Ellerman wrote:
> Laurent reported that STRICT_MODULE_RWX was causing intermittent crashes
> on one of his systems:
>
> kernel tried to execute exec-protected page (c008000004073278) - exploit
> attempt? (uid: 0)
> BUG: Unable to handle kernel instruction fetch
> Faulting instruction address: 0xc008000004073278
> Oops: Kernel access of bad area, sig: 11 [#1]
> LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries
> Modules linked in: drm virtio_console fuse drm_panel_orientation_quirks ...
> CPU: 3 PID: 44 Comm: kworker/3:1 Not tainted 5.14.0-rc4+ #12
> Workqueue: events control_work_handler [virtio_console]
> NIP: c008000004073278 LR: c008000004073278 CTR: c0000000001e9de0
> REGS: c00000002e4ef7e0 TRAP: 0400 Not tainted (5.14.0-rc4+)
> MSR: 800000004280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 24002822 XER:
> 200400cf
> ...
> NIP fill_queue+0xf0/0x210 [virtio_console]
> LR fill_queue+0xf0/0x210 [virtio_console]
> Call Trace:
> fill_queue+0xb4/0x210 [virtio_console] (unreliable)
> add_port+0x1a8/0x470 [virtio_console]
> control_work_handler+0xbc/0x1e8 [virtio_console]
> process_one_work+0x290/0x590
> worker_thread+0x88/0x620
> kthread+0x194/0x1a0
> ret_from_kernel_thread+0x5c/0x64
>
> [...]
Applied to powerpc/fixes.
[1/1] powerpc/mm: Fix set_memory_*() against concurrent accesses
https://git.kernel.org/powerpc/c/9f7853d7609d59172eecfc5e7ccf503bc1b690bd
cheers
