cve/2023/CVE-2023-52621.md

### [CVE-2023-52621](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-52621)
![](https://img.shields.io/static/v1?label=Product&message=Linux&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=1da177e4c3f4%3C%20d6d6fe4bb105%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:bpf: Check rcu_read_lock_trace_held() before calling bpf map helpersThese three bpf_map_{lookup,update,delete}_elem() helpers are alsoavailable for sleepable bpf program, so add the corresponding lockassertion for sleepable bpf program, otherwise the following warningwill be reported when a sleepable bpf program manipulates bpf map underinterpreter mode (aka bpf_jit_enable=0):  WARNING: CPU: 3 PID: 4985 at kernel/bpf/helpers.c:40 ......  CPU: 3 PID: 4985 Comm: test_progs Not tainted 6.6.0+ #2  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ......  RIP: 0010:bpf_map_lookup_elem+0x54/0x60  ......  Call Trace:   <TASK>   ? __warn+0xa5/0x240   ? bpf_map_lookup_elem+0x54/0x60   ? report_bug+0x1ba/0x1f0   ? handle_bug+0x40/0x80   ? exc_invalid_op+0x18/0x50   ? asm_exc_invalid_op+0x1b/0x20   ? __pfx_bpf_map_lookup_elem+0x10/0x10   ? rcu_lockdep_current_cpu_online+0x65/0xb0   ? rcu_is_watching+0x23/0x50   ? bpf_map_lookup_elem+0x54/0x60   ? __pfx_bpf_map_lookup_elem+0x10/0x10   ___bpf_prog_run+0x513/0x3b70   __bpf_prog_run32+0x9d/0xd0   ? __bpf_prog_enter_sleepable_recur+0xad/0x120   ? __bpf_prog_enter_sleepable_recur+0x3e/0x120   bpf_trampoline_6442580665+0x4d/0x1000   __x64_sys_getpgid+0x5/0x30   ? do_syscall_64+0x36/0xb0   entry_SYSCALL_64_after_hwframe+0x6e/0x76   </TASK>

### POC

#### Reference
No PoCs from references.

#### Github
- https://github.com/fkie-cad/nvd-json-data-feeds