From: Sukadev Bhattiprolu <sukadev@xxxxxxxxxxxxxxxxxx> As pointed out by Oren Laadan, we want to ensure that unused bits in the clone-flags remain unused and available for future. To ensure this, define a mask of clone-flags and check the flags in the clone() system calls. Changelog[v9]: - Include the unused clone-flag (CLONE_UNUSED) to VALID_CLONE_FLAGS to avoid breaking any applications that may have set it. IOW, this patch/check only applies to clone-flags bits 33 and higher. Changelog[v8]: - New patch in set Signed-off-by: Sukadev Bhattiprolu <sukadev@xxxxxxxxxxxxxxxxxx> Acked-by: Serge E. Hallyn <serue@xxxxxxxxxx> Tested-by: Serge E. Hallyn <serue@xxxxxxxxxx> Acked-by: Oren Laadan <orenl.cs.columbia.edu> --- include/linux/sched.h | 12 ++++++++++++ kernel/fork.c | 3 +++ 2 files changed, 15 insertions(+), 0 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index 78efe7c..d57eab8 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -29,6 +29,18 @@ #define CLONE_NEWNET 0x40000000 /* New network namespace */ #define CLONE_IO 0x80000000 /* Clone io context */ +#define CLONE_UNUSED 0x00001000 /* Can be reused ? */ + +#define VALID_CLONE_FLAGS (CSIGNAL | CLONE_VM | CLONE_FS | CLONE_FILES |\ + CLONE_SIGHAND | CLONE_UNUSED | CLONE_PTRACE |\ + CLONE_VFORK | CLONE_PARENT | CLONE_THREAD |\ + CLONE_NEWNS | CLONE_SYSVSEM | CLONE_SETTLS |\ + CLONE_PARENT_SETTID | CLONE_CHILD_CLEARTID |\ + CLONE_DETACHED | CLONE_UNTRACED |\ + CLONE_CHILD_SETTID | CLONE_STOPPED |\ + CLONE_NEWUTS | CLONE_NEWIPC | CLONE_NEWUSER |\ + CLONE_NEWPID | CLONE_NEWNET | CLONE_IO) + /* * Scheduling policies */ diff --git a/kernel/fork.c b/kernel/fork.c index 737bca9..f95cbd2 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -987,6 +987,9 @@ static struct task_struct *copy_process(unsigned long clone_flags, struct task_struct *p; int cgroup_callbacks_done = 0; + if (clone_flags & ~VALID_CLONE_FLAGS) + return ERR_PTR(-EINVAL); + if ((clone_flags & (CLONE_NEWNS|CLONE_FS)) == (CLONE_NEWNS|CLONE_FS)) return ERR_PTR(-EINVAL); -- 1.6.3.3 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>