High CPU utilization causing all new processes to segfault

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High CPU utilization causing all new processes to segfault

Postby mstm1 » Sun Jun 05, 2016 7:08 pm

It can be easily reproduced here by compiling a kernel. After 10-15 minutes the subprocesses will start to segfault and any attempt to start any new process under any user fails until the system is rebooted.

Occasionally it will spontaneously reboot rather than just cause new processes to segfault, but I haven't been able to track down the reason in either case yet, as no messages other than the single line segfault notices are printed on the console, running dmesg afterward also segfaults, and netconsole shows no new messages.

The grsec version it currently happens on is grsecurity-3.1-4.5.5-201605291201.patch with zfs v0.6.5.7 included as builtin at compile time. I can email the kernel config or image if needed, GRKERNSEC & PAX options below.

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Code: Select all
CONFIG_GRKERNSEC=y
CONFIG_GRKERNSEC_CONFIG_AUTO=y
# CONFIG_GRKERNSEC_CONFIG_CUSTOM is not set
# CONFIG_GRKERNSEC_CONFIG_SERVER is not set
CONFIG_GRKERNSEC_CONFIG_DESKTOP=y
CONFIG_GRKERNSEC_CONFIG_VIRT_NONE=y
# CONFIG_GRKERNSEC_CONFIG_VIRT_GUEST is not set
# CONFIG_GRKERNSEC_CONFIG_VIRT_HOST is not set
CONFIG_GRKERNSEC_CONFIG_PRIORITY_PERF=y
# CONFIG_GRKERNSEC_CONFIG_PRIORITY_SECURITY is not set
CONFIG_GRKERNSEC_PROC_GID=5000
CONFIG_GRKERNSEC_TPE_TRUSTED_GID=7000
CONFIG_GRKERNSEC_SYMLINKOWN_GID=6000
CONFIG_GRKERNSEC_KMEM=y
# CONFIG_GRKERNSEC_IO is not set
CONFIG_GRKERNSEC_BPF_HARDEN=y
CONFIG_GRKERNSEC_PERF_HARDEN=y
CONFIG_GRKERNSEC_RAND_THREADSTACK=y
CONFIG_GRKERNSEC_PROC_MEMMAP=y
CONFIG_GRKERNSEC_KSTACKOVERFLOW=y
# CONFIG_GRKERNSEC_BRUTE is not set
CONFIG_GRKERNSEC_MODHARDEN=y
# CONFIG_GRKERNSEC_HIDESYM is not set
# CONFIG_GRKERNSEC_RANDSTRUCT is not set
CONFIG_GRKERNSEC_KERN_LOCKOUT=y
# CONFIG_GRKERNSEC_NO_RBAC is not set
CONFIG_GRKERNSEC_ACL_HIDEKERN=y
CONFIG_GRKERNSEC_ACL_MAXTRIES=3
CONFIG_GRKERNSEC_ACL_TIMEOUT=30
CONFIG_GRKERNSEC_PROC=y
CONFIG_GRKERNSEC_PROC_USER=y
CONFIG_GRKERNSEC_PROC_ADD=y
CONFIG_GRKERNSEC_LINK=y
CONFIG_GRKERNSEC_SYMLINKOWN=y
CONFIG_GRKERNSEC_FIFO=y
# CONFIG_GRKERNSEC_SYSFS_RESTRICT is not set
# CONFIG_GRKERNSEC_ROFS is not set
CONFIG_GRKERNSEC_DEVICE_SIDECHANNEL=y
# CONFIG_GRKERNSEC_CHROOT is not set
# CONFIG_GRKERNSEC_AUDIT_GROUP is not set
# CONFIG_GRKERNSEC_EXECLOG is not set
# CONFIG_GRKERNSEC_RESLOG is not set
# CONFIG_GRKERNSEC_CHROOT_EXECLOG is not set
# CONFIG_GRKERNSEC_AUDIT_PTRACE is not set
# CONFIG_GRKERNSEC_AUDIT_CHDIR is not set
# CONFIG_GRKERNSEC_AUDIT_MOUNT is not set
CONFIG_GRKERNSEC_SIGNAL=y
CONFIG_GRKERNSEC_FORKFAIL=y
CONFIG_GRKERNSEC_TIME=y
CONFIG_GRKERNSEC_PROC_IPADDR=y
CONFIG_GRKERNSEC_RWXMAP_LOG=y
CONFIG_GRKERNSEC_DMESG=y
CONFIG_GRKERNSEC_HARDEN_PTRACE=y
CONFIG_GRKERNSEC_PTRACE_READEXEC=y
CONFIG_GRKERNSEC_SETXID=y
CONFIG_GRKERNSEC_HARDEN_IPC=y
CONFIG_GRKERNSEC_HARDEN_TTY=y
CONFIG_GRKERNSEC_TPE=y
CONFIG_GRKERNSEC_TPE_ALL=y
CONFIG_GRKERNSEC_TPE_INVERT=y
CONFIG_GRKERNSEC_TPE_GID=7000
CONFIG_GRKERNSEC_BLACKHOLE=y
CONFIG_GRKERNSEC_NO_SIMULT_CONNECT=y
# CONFIG_GRKERNSEC_SOCKET is not set
CONFIG_GRKERNSEC_DENYUSB=y
# CONFIG_GRKERNSEC_DENYUSB_FORCE is not set
CONFIG_GRKERNSEC_SYSCTL=y
CONFIG_GRKERNSEC_SYSCTL_ON=y
CONFIG_GRKERNSEC_FLOODTIME=10
CONFIG_GRKERNSEC_FLOODBURST=32


Code: Select all
CONFIG_PAX_KERNEXEC_PLUGIN=y
CONFIG_PAX_PER_CPU_PGD=y
CONFIG_PAX_USERCOPY_SLABS=y
CONFIG_PAX=y
# CONFIG_PAX_SOFTMODE is not set
# CONFIG_PAX_EI_PAX is not set
# CONFIG_PAX_PT_PAX_FLAGS is not set
CONFIG_PAX_XATTR_PAX_FLAGS=y
# CONFIG_PAX_NO_ACL_FLAGS is not set
CONFIG_PAX_HAVE_ACL_FLAGS=y
# CONFIG_PAX_HOOK_ACL_FLAGS is not set
CONFIG_PAX_NOEXEC=y
CONFIG_PAX_PAGEEXEC=y
CONFIG_PAX_EMUTRAMP=y
CONFIG_PAX_MPROTECT=y
# CONFIG_PAX_MPROTECT_COMPAT is not set
# CONFIG_PAX_ELFRELOCS is not set
CONFIG_PAX_KERNEXEC=y
# CONFIG_PAX_KERNEXEC_PLUGIN_METHOD_BTS is not set
CONFIG_PAX_KERNEXEC_PLUGIN_METHOD_OR=y
CONFIG_PAX_KERNEXEC_PLUGIN_METHOD="or"
CONFIG_PAX_ASLR=y
CONFIG_PAX_RANDKSTACK=y
CONFIG_PAX_RANDUSTACK=y
CONFIG_PAX_RANDMMAP=y
# CONFIG_PAX_MEMORY_SANITIZE is not set
CONFIG_PAX_MEMORY_STACKLEAK=y
CONFIG_PAX_MEMORY_STRUCTLEAK=y
# CONFIG_PAX_MEMORY_UDEREF is not set
CONFIG_PAX_REFCOUNT=y
CONFIG_PAX_CONSTIFY_PLUGIN=y
CONFIG_PAX_USERCOPY=y
# CONFIG_PAX_USERCOPY_DEBUG is not set
CONFIG_PAX_SIZE_OVERFLOW=y
CONFIG_PAX_LATENT_ENTROPY=y
# CONFIG_PAX_RAP is not set
mstm1
 
Posts: 1
Joined: Sun Jun 05, 2016 6:52 pm

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