In fork_init a division by zero may occur. In the first patch the calculation of max_threads is moved from fork_init to a new separate function.
The incorrect calculation of max threads is addressed in the second patch. Furthermore max_threads is checked against FUTEX_TID_MASK. The third patch addresses max_threads being set by writing to /proc/sys/kernel/threads-max. The same limits are applied as in fork_init. The fourth patch adds a description of threads-max to Documentation/sysctl/kernel.txt. New in version 6: Check against overflow of totalram_pages * PAGE_SIZE. Introduce argument of set_max_threads in 3rd patch where it is needed, not before. Update Documentation/sysctl/kernel.txt concerning threads-max. New in version 5: Do not update limits of the init process Do not update max_threads on memory hotplug events Corrections to commit messages New in version 4: Separation of refactoring and correction into separate patches (as requested by Ingo Molnar) Remove redundant argument of fork_init New in version 3: Determination of max_threads moved to separate function. Handling of /proc/sys/kernel/threads-max Handling of memory hotplugging. New in version 2: Use div64_u64 for 64-bit division. Thank you for your helpful feedback: Andrew Morton <a...@linux-foundation.org> David Rientjes <rient...@google.com> Guenter Roeck <li...@roeck-us.net> Ingo Molnar <mi...@kernel.org> Oleg Nesterov <o...@redhat.com> Peter Zijlstra <pet...@infradead.org> Vladimir Davydov <vdavy...@parallels.com> Heinrich Schuchardt (4): kernel/fork.c: new function for max_threads kernel/fork.c: avoid division by zero kernel/sysctl.c: threads-max observe limits Doc/sysctl/kernel.txt: document threads-max Documentation/sysctl/kernel.txt | 21 +++++++++++ include/linux/sysctl.h | 3 ++ init/main.c | 4 +-- kernel/fork.c | 78 ++++++++++++++++++++++++++++++++++------- kernel/sysctl.c | 6 ++-- 5 files changed, 93 insertions(+), 19 deletions(-) -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
