6cd0c583b0
The 'group' variable in sched_domain_debug_one() is not checked when firstly used in cpumask_test_cpu(cpu, sched_group_span(group)), but it might be NULL (it is checked later in the following while loop) and may cause NULL pointer dereference. We need to check it before using to avoid NULL dereference. Signed-off-by: Yi Wang <wang.yi59@zte.com.cn> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Jiang Biao <jiang.biao2@zte.com.cn> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: zhong.weidong@zte.com.cn Link: http://lkml.kernel.org/r/1532319547-33335-1-git-send-email-wang.yi59@zte.com.cn Signed-off-by: Ingo Molnar <mingo@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.