Xiaoming Ni cb5fe25c82 proc_sysctl: fix oops caused by incorrect command parameters ... commit 697edcb0e4eadc41645fe88c991fe6a206b1a08d upstream. The process_sysctl_arg() does not check whether val is empty before invoking strlen(val). If the command line parameter () is incorrectly configured and val is empty, oops is triggered. For example: "hung_task_panic=1" is incorrectly written as "hung_task_panic", oops is triggered. The call stack is as follows: Kernel command line: .... hung_task_panic ...... Call trace: __pi_strlen+0x10/0x98 parse_args+0x278/0x344 do_sysctl_args+0x8c/0xfc kernel_init+0x5c/0xf4 ret_from_fork+0x10/0x30 To fix it, check whether "val" is empty when "phram" is a sysctl field. Error codes are returned in the failure branch, and error logs are generated by parse_args(). Link: https://lkml.kernel.org/r/20210118133029.28580-1-nixiaoming@huawei.com Fixes: 3db978d480 ("kernel/sysctl: support setting sysctl parameters from kernel command line") Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Iurii Zaikin <yzaikin@google.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Heiner Kallweit <hkallweit1@gmail.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: <stable@vger.kernel.org> [5.8+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2021-01-27 11:55:14 +01:00
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array.c
base.c
bootconfig.c
cmdline.c
consoles.c
cpuinfo.c
devices.c
fd.c
fd.h
generic.c
inode.c
internal.h
interrupts.c
Kconfig
kcore.c
kmsg.c
loadavg.c
Makefile
meminfo.c
namespaces.c
nommu.c
page.c
proc_net.c
proc_sysctl.c	proc_sysctl: fix oops caused by incorrect command parameters	2021-01-27 11:55:14 +01:00
proc_tty.c
root.c
self.c
softirqs.c
stat.c
task_mmu.c	mm: don't play games with pinned pages in clear_page_refs	2021-01-19 18:27:29 +01:00
task_nommu.c
thread_self.c
uptime.c
util.c
version.c
vmcore.c