cve/2024/CVE-2024-56701.md

### [CVE-2024-56701](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2024-56701)
![](https://img.shields.io/static/v1?label=Product&message=Linux&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=06220d78f24a20549757be1014e57c382406cc92%3C%206956c0e7346ce1bbfc726755aa8da10d26e84276%20&color=brighgreen)
![](https://img.shields.io/static/v1?label=Vulnerability&message=n%2Fa&color=brighgreen)

### Description

In the Linux kernel, the following vulnerability has been resolved:powerpc/pseries: Fix dtl_access_lock to be a rw_semaphoreThe dtl_access_lock needs to be a rw_sempahore, a sleeping lock, becausethe code calls kmalloc() while holding it, which can sleep:  # echo 1 > /proc/powerpc/vcpudispatch_stats  BUG: sleeping function called from invalid context at include/linux/sched/mm.h:337  in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 199, name: sh  preempt_count: 1, expected: 0  3 locks held by sh/199:   #0: c00000000a0743f8 (sb_writers#3){.+.+}-{0:0}, at: vfs_write+0x324/0x438   #1: c0000000028c7058 (dtl_enable_mutex){+.+.}-{3:3}, at: vcpudispatch_stats_write+0xd4/0x5f4   #2: c0000000028c70b8 (dtl_access_lock){+.+.}-{2:2}, at: vcpudispatch_stats_write+0x220/0x5f4  CPU: 0 PID: 199 Comm: sh Not tainted 6.10.0-rc4 #152  Hardware name: IBM pSeries (emulated by qemu) POWER9 (raw) 0x4e1202 0xf000005 of:SLOF,HEAD hv:linux,kvm pSeries  Call Trace:    dump_stack_lvl+0x130/0x148 (unreliable)    __might_resched+0x174/0x410    kmem_cache_alloc_noprof+0x340/0x3d0    alloc_dtl_buffers+0x124/0x1ac    vcpudispatch_stats_write+0x2a8/0x5f4    proc_reg_write+0xf4/0x150    vfs_write+0xfc/0x438    ksys_write+0x88/0x148    system_call_exception+0x1c4/0x5a0    system_call_common+0xf4/0x258

### POC

#### Reference
No PoCs from references.

#### Github
- https://github.com/cku-heise/euvd-api-doc