From 0ed96051531ecc6965f6456d25b19b9b6bdb5c28 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 13 Apr 2021 13:33:51 -0700 Subject: [PATCH] rseq: Remove redundant access_ok() After commit 8f2817701492 ("rseq: Use get_user/put_user rather than __get_user/__put_user") we no longer need an access_ok() call from __rseq_handle_notify_resume() Mathieu pointed out the same cleanup can be done in rseq_syscall(). Signed-off-by: Eric Dumazet Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Mathieu Desnoyers Link: https://lkml.kernel.org/r/20210413203352.71350-3-eric.dumazet@gmail.com --- kernel/rseq.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/kernel/rseq.c b/kernel/rseq.c index f020f18f512a..cfe01ab5253c 100644 --- a/kernel/rseq.c +++ b/kernel/rseq.c @@ -273,8 +273,6 @@ void __rseq_handle_notify_resume(struct ksignal *ksig, struct pt_regs *regs) if (unlikely(t->flags & PF_EXITING)) return; - if (unlikely(!access_ok(t->rseq, sizeof(*t->rseq)))) - goto error; ret = rseq_ip_fixup(regs); if (unlikely(ret < 0)) goto error; @@ -301,8 +299,7 @@ void rseq_syscall(struct pt_regs *regs) if (!t->rseq) return; - if (!access_ok(t->rseq, sizeof(*t->rseq)) || - rseq_get_rseq_cs(t, &rseq_cs) || in_rseq_cs(ip, &rseq_cs)) + if (rseq_get_rseq_cs(t, &rseq_cs) || in_rseq_cs(ip, &rseq_cs)) force_sig(SIGSEGV); }