diff options
authorMichael Kerrisk <mtk.manpages@gmail.com>2014-05-09 16:54:15 +0200
committerShow Liu <show.liu@linaro.org>2014-06-18 12:05:23 +0800
commit6d63822a84a707217878bc7c3ac33e7bbd7ef0ee (patch)
parent1086a7c8498c4f420ea8838350c402d4a1fc1db4 (diff)
sched: Make sched_setattr() correctly return -EFBIG
commit 143cf23df25b7082cd706c3c53188e741e7881c3 upstream. The documented[1] behavior of sched_attr() in the proposed man page text is: sched_attr::size must be set to the size of the structure, as in sizeof(struct sched_attr), if the provided structure is smaller than the kernel structure, any additional fields are assumed '0'. If the provided structure is larger than the kernel structure, the kernel verifies all additional fields are '0' if not the syscall will fail with -E2BIG. As currently implemented, sched_copy_attr() returns -EFBIG for for this case, but the logic in sys_sched_setattr() converts that error to -EFAULT. This patch fixes the behavior. [1] http://thread.gmane.org/gmane.linux.kernel/1615615/focus=1697760 Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/536CEC17.9070903@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 files changed, 3 insertions, 2 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index c87074ae554..5dd2f8daec4 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -3680,8 +3680,9 @@ SYSCALL_DEFINE3(sched_setattr, pid_t, pid, struct sched_attr __user *, uattr,
if (!uattr || pid < 0 || flags)
return -EINVAL;
- if (sched_copy_attr(uattr, &attr))
- return -EFAULT;
+ retval = sched_copy_attr(uattr, &attr);
+ if (retval)
+ return retval;
if (attr.sched_policy < 0)
return -EINVAL;