Messages in this thread Patch in this message | | | Subject | [RFC 12/12][PATCH] SCHED_DEADLINE: modified sched_*_ex API | From | Raistlin <> | Date | Fri, 16 Oct 2009 17:48:06 +0200 |
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This commit amends the new API introduced to deal with the new sched_param_ex scheduling parameter data structure.
What we add is one more parameter to all the functions, containing the size of sched_param_ex. It might turn out useful in possible future extensions of sched_param_ex itself, to avoid issue with ABI of legacy applications.
Signed-off-by: Raistlin <raistlin@linux.it> --- include/linux/syscalls.h | 6 +++--- kernel/sched.c | 25 ++++++++++++++++--------- 2 files changed, 19 insertions(+), 12 deletions(-)
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index e01f59c..60a99a7 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -391,16 +391,16 @@ asmlinkage long sys_clock_nanosleep(clockid_t which_clock, int flags, asmlinkage long sys_nice(int increment); asmlinkage long sys_sched_setscheduler(pid_t pid, int policy, struct sched_param __user *param); -asmlinkage long sys_sched_setscheduler_ex(pid_t pid, int policy, +asmlinkage long sys_sched_setscheduler_ex(pid_t pid, int policy, unsigned len, struct sched_param_ex __user *param); asmlinkage long sys_sched_setparam(pid_t pid, struct sched_param __user *param); -asmlinkage long sys_sched_setparam_ex(pid_t pid, +asmlinkage long sys_sched_setparam_ex(pid_t pid, unsigned len, struct sched_param_ex __user *param); asmlinkage long sys_sched_getscheduler(pid_t pid); asmlinkage long sys_sched_getparam(pid_t pid, struct sched_param __user *param); -asmlinkage long sys_sched_getparam_ex(pid_t pid, +asmlinkage long sys_sched_getparam_ex(pid_t pid, unsigned len, struct sched_param_ex __user *param); asmlinkage long sys_sched_setaffinity(pid_t pid, unsigned int len, unsigned long __user *user_mask_ptr); diff --git a/kernel/sched.c b/kernel/sched.c index a8ebfa2..d3a61f5 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -6662,7 +6662,7 @@ do_sched_setscheduler(pid_t pid, int policy, struct sched_param __user *param) } static int -do_sched_setscheduler_ex(pid_t pid, int policy, +do_sched_setscheduler_ex(pid_t pid, int policy, unsigned int len, struct sched_param_ex __user *param_ex) { struct sched_param lparam; @@ -6672,8 +6672,9 @@ do_sched_setscheduler_ex(pid_t pid, int policy, if (!param_ex || pid < 0) return -EINVAL; - if (copy_from_user(&lparam_ex, param_ex, - sizeof(struct sched_param_ex))) + if (len > sizeof(struct sched_param_ex)) + return -EINVAL; + if (copy_from_user(&lparam_ex, param_ex,len)) return -EFAULT; rcu_read_lock(); @@ -6708,15 +6709,17 @@ SYSCALL_DEFINE3(sched_setscheduler, pid_t, pid, int, policy, * sys_sched_setscheduler_ex - set/change the scheduler policy to SCHED_DEADLINE * @pid: the pid in question. * @policy: new policy (should be SCHED_DEADLINE). + * @len: size of data pointed by param_ex. * @param: structure containg the extended deadline parameters. */ -SYSCALL_DEFINE3(sched_setscheduler_ex, pid_t, pid, int, policy, +SYSCALL_DEFINE4(sched_setscheduler_ex, pid_t, pid, + int, policy, unsigned, len, struct sched_param_ex __user *, param_ex) { if (policy < 0) return -EINVAL; - return do_sched_setscheduler_ex(pid, policy, param_ex); + return do_sched_setscheduler_ex(pid, policy, len, param_ex); } /** @@ -6732,12 +6735,13 @@ SYSCALL_DEFINE2(sched_setparam, pid_t, pid, struct sched_param __user *, param) /** * sys_sched_setparam - set/change the DEADLINE parameters of a thread * @pid: the pid in question. + * @len: size of data pointed by param_ex. * @param_ex: structure containing the new parameters (deadline, runtime, etc.). */ -SYSCALL_DEFINE2(sched_setparam_ex, pid_t, pid, +SYSCALL_DEFINE3(sched_setparam_ex, pid_t, pid, unsigned, len, struct sched_param_ex __user *, param_ex) { - return do_sched_setscheduler_ex(pid, -1, param_ex); + return do_sched_setscheduler_ex(pid, -1, len, param_ex); } /** @@ -6807,9 +6811,10 @@ out_unlock: /** * sys_sched_getparam - get the DEADLINE task parameters of a thread * @pid: the pid in question. + * @len: size of data pointed by param_ex. * @param_ex: structure containing the new parameters (deadline, runtime, etc.). */ -SYSCALL_DEFINE2(sched_getparam_ex, pid_t, pid, +SYSCALL_DEFINE3(sched_getparam_ex, pid_t, pid, unsigned, len, struct sched_param_ex __user *, param_ex) { struct sched_param_ex lp; @@ -6818,6 +6823,8 @@ SYSCALL_DEFINE2(sched_getparam_ex, pid_t, pid, if (!param_ex || pid < 0) return -EINVAL; + if (len < sizeof(struct sched_param_ex)) + return -EINVAL; read_lock(&tasklist_lock); p = find_process_by_pid(pid); @@ -6837,7 +6844,7 @@ SYSCALL_DEFINE2(sched_getparam_ex, pid_t, pid, /* * This one might sleep, we cannot do it with a spinlock held ... */ - retval = copy_to_user(param_ex, &lp, sizeof(*param_ex)) ? -EFAULT : 0; + retval = copy_to_user(param_ex, &lp, len) ? -EFAULT : 0; return retval; -- 1.6.0.4 -- <<This happens because I choose it to happen!>> (Raistlin Majere) ---------------------------------------------------------------------- Dario Faggioli, ReTiS Lab, Scuola Superiore Sant'Anna, Pisa (Italy) http://blog.linux.it/raistlin / raistlin@ekiga.net / dario.faggioli@jabber.org [unhandled content-type:application/pgp-signature] | |