CVE:CVE-2015-4170
CNNVD:CNNVD-201506-088
Linux kernel是美国Linux基金会发布的开源操作系统Linux所使用的内核。NFSv4 implementation是其中的一个分布式文件系统协议。
Linux kernel 3.13-rc4-next-20131218之前版本的drivers/tty/tty_ldsem.c文件中的‘ldsem_cmpxchg’函数存在竞争条件漏洞。本地攻击者可通过在关闭tty进程期间建立一个新的tty进程利用该漏洞造成拒绝服务（ldsem_down_read和ldsem_down_write死锁）。
solution:Upgrade linux linux_kernel to a higher version than 3.13.3,and avoid the version (,3.13.3]; Upgrade redhat enterprise_linux_compute_node_eus to a higher version than 7.1,and avoid the version 7.1; Upgrade redhat enterprise_linux_for_ibm_z_systems_eus to a higher version than 7.1_s390x,and avoid the version 7.1_s390x; Upgrade redhat enterprise_linux_for_power_big_endian_eus to a higher version than 7.1_ppc64,and avoid the version 7.1_ppc64; Upgrade redhat enterprise_linux_for_power_little_endian_eus to a higher version than 7.1_ppc64le,and avoid the version 7.1_ppc64le; Upgrade redhat enterprise_linux_server_eus to a higher version than 7.1,and avoid the version 7.1