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Ensure the updates are >> done in lockstep in case we error out on a write to user-space. >> >> Fixes: 7d5265ffcd8b ("rseq: Validate read-only fields under DEBUG_RSEQ config") >> Signed-off-by: Michael Jeanson >> Reviewed-by: Mathieu Desnoyers >> --- >> kernel/rseq.c | 85 +++++++++++++++++++++++++++------------------------ >> 1 file changed, 45 insertions(+), 40 deletions(-) >> >> diff --git a/kernel/rseq.c b/kernel/rseq.c >> index 2cb16091ec0a..88aa780f8cf4 100644 >> --- a/kernel/rseq.c >> +++ b/kernel/rseq.c >> @@ -26,6 +26,11 @@ >> RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL | \ >> RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE) >> >> +static struct rseq __user *rseq_user_fields(struct task_struct *t) >> +{ >> + return (struct rseq __user *) t->rseq; > > Why is this wrapper needed? > > task_struct::rseq is already of that exact type AFAICS: > > struct rseq __user *rseq; It's not needed, I can remove it and resend. Thanks, Michael