Commit-ID: 4efbc454ba68def5ef285b26ebfcfdb605b52755 Gitweb: http://git.kernel.org/tip/4efbc454ba68def5ef285b26ebfcfdb605b52755 Author: Vegard Nossum <vegard.nossum@xxxxxxxxxx> AuthorDate: Sun, 16 Feb 2014 22:24:17 +0100 Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx> CommitDate: Fri, 21 Feb 2014 21:27:10 +0100 sched: Fix information leak in sys_sched_getattr() We're copying the on-stack structure to userspace, but forgot to give the right number of bytes to copy. This allows the calling process to obtain up to PAGE_SIZE bytes from the stack (and possibly adjacent kernel memory). This fix copies only as much as we actually have on the stack (attr->size defaults to the size of the struct) and leaves the rest of the userspace-provided buffer untouched. Found using kmemcheck + trinity. Fixes: d50dde5a10f30 ("sched: Add new scheduler syscalls to support an extended scheduling parameters ABI") Cc: Dario Faggioli <raistlin@xxxxxxxx> Cc: Juri Lelli <juri.lelli@xxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Signed-off-by: Vegard Nossum <vegard.nossum@xxxxxxxxxx> Signed-off-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/1392585857-10725-1-git-send-email-vegard.nossum@xxxxxxxxxx Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> --- kernel/sched/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 33d030a..a6e7470 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3786,7 +3786,7 @@ static int sched_read_attr(struct sched_attr __user *uattr, attr->size = usize; } - ret = copy_to_user(uattr, attr, usize); + ret = copy_to_user(uattr, attr, attr->size); if (ret) return -EFAULT; -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html