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From: Al Viro <viro@ZenIV.linux.org.uk>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>, linux-kernel@vger.kernel.org
Subject: [RFC][PATCH 3/7] [parisc, s390, sparc64] no need for access_ok() in futex handling
Date: Mon, 23 Mar 2020 18:51:23 +0000	[thread overview]
Message-ID: <20200323185127.252501-3-viro@ZenIV.linux.org.uk> (raw)
In-Reply-To: <20200323185127.252501-1-viro@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

access_ok() is always true on those

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 arch/parisc/include/asm/futex.h   | 3 ---
 arch/s390/include/asm/futex.h     | 2 --
 arch/sparc/include/asm/futex_64.h | 2 --
 3 files changed, 7 deletions(-)

diff --git a/arch/parisc/include/asm/futex.h b/arch/parisc/include/asm/futex.h
index c10cc9010cc1..c459f656c8c3 100644
--- a/arch/parisc/include/asm/futex.h
+++ b/arch/parisc/include/asm/futex.h
@@ -39,9 +39,6 @@ arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr)
 	int oldval, ret;
 	u32 tmp;
 
-	if (!access_ok(uaddr, sizeof(u32)))
-		return -EFAULT;
-
 	_futex_spin_lock_irqsave(uaddr, &flags);
 
 	ret = -EFAULT;
diff --git a/arch/s390/include/asm/futex.h b/arch/s390/include/asm/futex.h
index ed965c3ecd5b..26f9144562c9 100644
--- a/arch/s390/include/asm/futex.h
+++ b/arch/s390/include/asm/futex.h
@@ -28,8 +28,6 @@ static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval,
 	int oldval = 0, newval, ret;
 	mm_segment_t old_fs;
 
-	if (!access_ok(uaddr, sizeof(u32)))
-		return -EFAULT;
 	old_fs = enable_sacf_uaccess();
 	switch (op) {
 	case FUTEX_OP_SET:
diff --git a/arch/sparc/include/asm/futex_64.h b/arch/sparc/include/asm/futex_64.h
index 84fffaaf59d3..72de967318d7 100644
--- a/arch/sparc/include/asm/futex_64.h
+++ b/arch/sparc/include/asm/futex_64.h
@@ -35,8 +35,6 @@ static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval,
 {
 	int oldval = 0, ret, tem;
 
-	if (!access_ok(uaddr, sizeof(u32)))
-		return -EFAULT;
 	if (unlikely((((unsigned long) uaddr) & 0x3UL)))
 		return -EINVAL;
 
-- 
2.11.0


  parent reply	other threads:[~2020-03-23 18:51 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-23 18:50 [RFC][PATCHSET] futex uaccess cleanups Al Viro
2020-03-23 18:51 ` [RFC][PATCH 1/7] futex: arch_futex_atomic_op_inuser() calling conventions change Al Viro
2020-03-23 18:51   ` [RFC][PATCH 2/7] sh: no need of access_ok() in arch_futex_atomic_op_inuser() Al Viro
2020-03-23 18:51   ` Al Viro [this message]
2020-03-23 18:51   ` [RFC][PATCH 4/7] objtool: whitelist __sanitizer_cov_trace_switch() Al Viro
2020-03-23 18:51   ` [RFC][PATCH 5/7] x86: convert arch_futex_atomic_op_inuser() to user_access_begin/user_access_end() Al Viro
2020-03-23 19:06     ` Linus Torvalds
2020-03-24  2:08       ` Al Viro
2020-03-24 16:19         ` Linus Torvalds
2020-03-24 20:42           ` Al Viro
2020-03-24 20:57             ` Linus Torvalds
2020-03-27  2:42               ` Al Viro
2020-03-27  3:42                 ` Linus Torvalds
2020-03-27  3:49                   ` Linus Torvalds
2020-03-27  4:03                     ` Linus Torvalds
2020-03-27  4:35                       ` Josh Poimboeuf
2020-03-23 18:51   ` [RFC][PATCH 6/7] generic arch_futex_atomic_op_inuser() doesn't need access_ok() Al Viro
2020-03-23 18:51   ` [RFC][PATCH 7/7] x86: get rid of user_atomic_cmpxchg_inatomic() Al Viro

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