Remove 'type' argument from access_ok() function

Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.

It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access.  But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.

A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model.  And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.

This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.

There were a couple of notable cases:

 - csky still had the old "verify_area()" name as an alias.

 - the iter_iov code had magical hardcoded knowledge of the actual
   values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
   really used it)

 - microblaze used the type argument for a debug printout

but other than those oddities this should be a total no-op patch.

I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something.  Any missed conversion should be trivially fixable, though.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

12 files changed, 47 insertions, 42 deletions

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 0607db304def..b155cd17c1bd 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -79,7 +79,7 @@ int bpf_check_uarg_tail_zero(void __user *uaddr,
         if (unlikely(actual_size > PAGE_SIZE))  /* silly large */
                 return -E2BIG;
 
-        if (unlikely(!access_ok(VERIFY_READ, uaddr, actual_size)))
+        if (unlikely(!access_ok(uaddr, actual_size)))
                 return -EFAULT;
 
         if (actual_size <= expected_size)
diff --git a/kernel/compat.c b/kernel/compat.c
index 089d00d0da9c..705d4ae6c018 100644
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -95,28 +95,28 @@ int compat_put_timex(struct compat_timex __user *utp, const struct timex *txc)
 
 static int __compat_get_timeval(struct timeval *tv, const struct old_timeval32 __user *ctv)
 {
-        return (!access_ok(VERIFY_READ, ctv, sizeof(*ctv)) ||
+        return (!access_ok(ctv, sizeof(*ctv)) ||
                         __get_user(tv->tv_sec, &ctv->tv_sec) ||
                         __get_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0;
 }
 
 static int __compat_put_timeval(const struct timeval *tv, struct old_timeval32 __user *ctv)
 {
-        return (!access_ok(VERIFY_WRITE, ctv, sizeof(*ctv)) ||
+        return (!access_ok(ctv, sizeof(*ctv)) ||
                         __put_user(tv->tv_sec, &ctv->tv_sec) ||
                         __put_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0;
 }
 
 static int __compat_get_timespec(struct timespec *ts, const struct old_timespec32 __user *cts)
 {
-        return (!access_ok(VERIFY_READ, cts, sizeof(*cts)) ||
+        return (!access_ok(cts, sizeof(*cts)) ||
                         __get_user(ts->tv_sec, &cts->tv_sec) ||
                         __get_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
 }
 
 static int __compat_put_timespec(const struct timespec *ts, struct old_timespec32 __user *cts)
 {
-        return (!access_ok(VERIFY_WRITE, cts, sizeof(*cts)) ||
+        return (!access_ok(cts, sizeof(*cts)) ||
                         __put_user(ts->tv_sec, &cts->tv_sec) ||
                         __put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
 }
@@ -335,7 +335,7 @@ int get_compat_sigevent(struct sigevent *event,
                 const struct compat_sigevent __user *u_event)
 {
         memset(event, 0, sizeof(*event));
-        return (!access_ok(VERIFY_READ, u_event, sizeof(*u_event)) ||
+        return (!access_ok(u_event, sizeof(*u_event)) ||
                 __get_user(event->sigev_value.sival_int,
                         &u_event->sigev_value.sival_int) ||
                 __get_user(event->sigev_signo, &u_event->sigev_signo) ||
@@ -354,7 +354,7 @@ long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask,
         bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
         nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
 
-        if (!access_ok(VERIFY_READ, umask, bitmap_size / 8))
+        if (!access_ok(umask, bitmap_size / 8))
                 return -EFAULT;
 
         user_access_begin();
@@ -384,7 +384,7 @@ long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
         bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
         nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
 
-        if (!access_ok(VERIFY_WRITE, umask, bitmap_size / 8))
+        if (!access_ok(umask, bitmap_size / 8))
                 return -EFAULT;
 
         user_access_begin();
@@ -438,7 +438,7 @@ void __user *compat_alloc_user_space(unsigned long len)
 
         ptr = arch_compat_alloc_user_space(len);
 
-        if (unlikely(!access_ok(VERIFY_WRITE, ptr, len)))
+        if (unlikely(!access_ok(ptr, len)))
                 return NULL;
 
         return ptr;
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 67ecac337374..3cd13a30f732 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -10135,7 +10135,7 @@ static int perf_copy_attr(struct perf_event_attr __user *uattr,
         u32 size;
         int ret;
 
-        if (!access_ok(VERIFY_WRITE, uattr, PERF_ATTR_SIZE_VER0))
+        if (!access_ok(uattr, PERF_ATTR_SIZE_VER0))
                 return -EFAULT;
 
         /*
diff --git a/kernel/exit.c b/kernel/exit.c
index 0e21e6d21f35..8a01b671dc1f 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -1604,7 +1604,7 @@ SYSCALL_DEFINE5(waitid, int, which, pid_t, upid, struct siginfo __user *,
         if (!infop)
                 return err;
 
-        if (!access_ok(VERIFY_WRITE, infop, sizeof(*infop)))
+        if (!access_ok(infop, sizeof(*infop)))
                 return -EFAULT;
 
         user_access_begin();
@@ -1732,7 +1732,7 @@ COMPAT_SYSCALL_DEFINE5(waitid,
         if (!infop)
                 return err;
 
-        if (!access_ok(VERIFY_WRITE, infop, sizeof(*infop)))
+        if (!access_ok(infop, sizeof(*infop)))
                 return -EFAULT;
 
         user_access_begin();
diff --git a/kernel/futex.c b/kernel/futex.c
index 054105854e0e..be3bff2315ff 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -481,13 +481,18 @@ static void drop_futex_key_refs(union futex_key *key)
         }
 }
 
+enum futex_access {
+        FUTEX_READ,
+        FUTEX_WRITE
+};
+
 /**
  * get_futex_key() - Get parameters which are the keys for a futex
  * @uaddr:      virtual address of the futex
  * @fshared:    0 for a PROCESS_PRIVATE futex, 1 for PROCESS_SHARED
  * @key:        address where result is stored.
- * @rw:         mapping needs to be read/write (values: VERIFY_READ,
- *              VERIFY_WRITE)
+ * @rw:         mapping needs to be read/write (values: FUTEX_READ,
+ *              FUTEX_WRITE)
  *
  * Return: a negative error code or 0
  *
@@ -500,7 +505,7 @@ static void drop_futex_key_refs(union futex_key *key)
  * lock_page() might sleep, the caller should not hold a spinlock.
  */
 static int
-get_futex_key(u32 __user *uaddr, int fshared, union futex_key *key, int rw)
+get_futex_key(u32 __user *uaddr, int fshared, union futex_key *key, enum futex_access rw)
 {
         unsigned long address = (unsigned long)uaddr;
         struct mm_struct *mm = current->mm;
@@ -516,7 +521,7 @@ get_futex_key(u32 __user *uaddr, int fshared, union futex_key *key, int rw)
                 return -EINVAL;
         address -= key->both.offset;
 
-        if (unlikely(!access_ok(rw, uaddr, sizeof(u32))))
+        if (unlikely(!access_ok(uaddr, sizeof(u32))))
                 return -EFAULT;
 
         if (unlikely(should_fail_futex(fshared)))
@@ -546,7 +551,7 @@ again:
          * If write access is not required (eg. FUTEX_WAIT), try
          * and get read-only access.
          */
-        if (err == -EFAULT && rw == VERIFY_READ) {
+        if (err == -EFAULT && rw == FUTEX_READ) {
                 err = get_user_pages_fast(address, 1, 0, &page);
                 ro = 1;
         }
@@ -1583,7 +1588,7 @@ futex_wake(u32 __user *uaddr, unsigned int flags, int nr_wake, u32 bitset)
         if (!bitset)
                 return -EINVAL;
 
-        ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &key, VERIFY_READ);
+        ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &key, FUTEX_READ);
         if (unlikely(ret != 0))
                 goto out;
 
@@ -1642,7 +1647,7 @@ static int futex_atomic_op_inuser(unsigned int encoded_op, u32 __user *uaddr)
                 oparg = 1 << oparg;
         }
 
-        if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
+        if (!access_ok(uaddr, sizeof(u32)))
                 return -EFAULT;
 
         ret = arch_futex_atomic_op_inuser(op, oparg, &oldval, uaddr);
@@ -1682,10 +1687,10 @@ futex_wake_op(u32 __user *uaddr1, unsigned int flags, u32 __user *uaddr2,
         DEFINE_WAKE_Q(wake_q);
 
 retry:
-        ret = get_futex_key(uaddr1, flags & FLAGS_SHARED, &key1, VERIFY_READ);
+        ret = get_futex_key(uaddr1, flags & FLAGS_SHARED, &key1, FUTEX_READ);
         if (unlikely(ret != 0))
                 goto out;
-        ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2, VERIFY_WRITE);
+        ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2, FUTEX_WRITE);
         if (unlikely(ret != 0))
                 goto out_put_key1;
 
@@ -1961,11 +1966,11 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
         }
 
 retry:
-        ret = get_futex_key(uaddr1, flags & FLAGS_SHARED, &key1, VERIFY_READ);
+        ret = get_futex_key(uaddr1, flags & FLAGS_SHARED, &key1, FUTEX_READ);
         if (unlikely(ret != 0))
                 goto out;
         ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2,
-                            requeue_pi ? VERIFY_WRITE : VERIFY_READ);
+                            requeue_pi ? FUTEX_WRITE : FUTEX_READ);
         if (unlikely(ret != 0))
                 goto out_put_key1;
 
@@ -2634,7 +2639,7 @@ static int futex_wait_setup(u32 __user *uaddr, u32 val, unsigned int flags,
          * while the syscall executes.
          */
 retry:
-        ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &q->key, VERIFY_READ);
+        ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &q->key, FUTEX_READ);
         if (unlikely(ret != 0))
                 return ret;
 
@@ -2793,7 +2798,7 @@ static int futex_lock_pi(u32 __user *uaddr, unsigned int flags,
         }
 
 retry:
-        ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &q.key, VERIFY_WRITE);
+        ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &q.key, FUTEX_WRITE);
         if (unlikely(ret != 0))
                 goto out;
 
@@ -2972,7 +2977,7 @@ retry:
         if ((uval & FUTEX_TID_MASK) != vpid)
                 return -EPERM;
 
-        ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &key, VERIFY_WRITE);
+        ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &key, FUTEX_WRITE);
         if (ret)
                 return ret;
 
@@ -3199,7 +3204,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
          */
         rt_mutex_init_waiter(&rt_waiter);
 
-        ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2, VERIFY_WRITE);
+        ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2, FUTEX_WRITE);
         if (unlikely(ret != 0))
                 goto out;
 
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 1306fe0c1dc6..d3d170374ceb 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -1466,7 +1466,7 @@ int do_syslog(int type, char __user *buf, int len, int source)
                         return -EINVAL;
                 if (!len)
                         return 0;
-                if (!access_ok(VERIFY_WRITE, buf, len))
+                if (!access_ok(buf, len))
                         return -EFAULT;
                 error = wait_event_interruptible(log_wait,
                                                  syslog_seq != log_next_seq);
@@ -1484,7 +1484,7 @@ int do_syslog(int type, char __user *buf, int len, int source)
                         return -EINVAL;
                 if (!len)
                         return 0;
-                if (!access_ok(VERIFY_WRITE, buf, len))
+                if (!access_ok(buf, len))
                         return -EFAULT;
                 error = syslog_print_all(buf, len, clear);
                 break;
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index c2cee9db5204..771e93f9c43f 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -1073,7 +1073,7 @@ int ptrace_request(struct task_struct *child, long request,
                 struct iovec kiov;
                 struct iovec __user *uiov = datavp;
 
-                if (!access_ok(VERIFY_WRITE, uiov, sizeof(*uiov)))
+                if (!access_ok(uiov, sizeof(*uiov)))
                         return -EFAULT;
 
                 if (__get_user(kiov.iov_base, &uiov->iov_base) ||
@@ -1229,7 +1229,7 @@ int compat_ptrace_request(struct task_struct *child, compat_long_t request,
                 compat_uptr_t ptr;
                 compat_size_t len;
 
-                if (!access_ok(VERIFY_WRITE, uiov, sizeof(*uiov)))
+                if (!access_ok(uiov, sizeof(*uiov)))
                         return -EFAULT;
 
                 if (__get_user(ptr, &uiov->iov_base) ||
diff --git a/kernel/rseq.c b/kernel/rseq.c
index c6242d8594dc..25e9a7b60eba 100644
--- a/kernel/rseq.c
+++ b/kernel/rseq.c
@@ -267,7 +267,7 @@ void __rseq_handle_notify_resume(struct ksignal *ksig, struct pt_regs *regs)
 
         if (unlikely(t->flags & PF_EXITING))
                 return;
-        if (unlikely(!access_ok(VERIFY_WRITE, t->rseq, sizeof(*t->rseq))))
+        if (unlikely(!access_ok(t->rseq, sizeof(*t->rseq))))
                 goto error;
         ret = rseq_ip_fixup(regs);
         if (unlikely(ret < 0))
@@ -295,7 +295,7 @@ void rseq_syscall(struct pt_regs *regs)
 
         if (!t->rseq)
                 return;
-        if (!access_ok(VERIFY_READ, t->rseq, sizeof(*t->rseq)) ||
+        if (!access_ok(t->rseq, sizeof(*t->rseq)) ||
             rseq_get_rseq_cs(t, &rseq_cs) || in_rseq_cs(ip, &rseq_cs))
                 force_sig(SIGSEGV, t);
 }
@@ -351,7 +351,7 @@ SYSCALL_DEFINE4(rseq, struct rseq __user *, rseq, u32, rseq_len,
         if (!IS_ALIGNED((unsigned long)rseq, __alignof__(*rseq)) ||
             rseq_len != sizeof(*rseq))
                 return -EINVAL;
-        if (!access_ok(VERIFY_WRITE, rseq, rseq_len))
+        if (!access_ok(rseq, rseq_len))
                 return -EFAULT;
         current->rseq = rseq;
         current->rseq_len = rseq_len;
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index f66920173370..1f3e19fd6dc6 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -4450,7 +4450,7 @@ static int sched_copy_attr(struct sched_attr __user *uattr, struct sched_attr *a
         u32 size;
         int ret;
 
-        if (!access_ok(VERIFY_WRITE, uattr, SCHED_ATTR_SIZE_VER0))
+        if (!access_ok(uattr, SCHED_ATTR_SIZE_VER0))
                 return -EFAULT;
 
         /* Zero the full structure, so that a short copy will be nice: */
@@ -4650,7 +4650,7 @@ static int sched_read_attr(struct sched_attr __user *uattr,
 {
         int ret;
 
-        if (!access_ok(VERIFY_WRITE, uattr, usize))
+        if (!access_ok(uattr, usize))
                 return -EFAULT;
 
         /*
diff --git a/kernel/signal.c b/kernel/signal.c
index 53e07d97ffe0..e1d7ad8e6ab1 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -3997,7 +3997,7 @@ SYSCALL_DEFINE3(sigaction, int, sig,
 
         if (act) {
                 old_sigset_t mask;
-                if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
+                if (!access_ok(act, sizeof(*act)) ||
                     __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
                     __get_user(new_ka.sa.sa_restorer, &act->sa_restorer) ||
                     __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
@@ -4012,7 +4012,7 @@ SYSCALL_DEFINE3(sigaction, int, sig,
         ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
 
         if (!ret && oact) {
-                if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
+                if (!access_ok(oact, sizeof(*oact)) ||
                     __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
                     __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer) ||
                     __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
@@ -4034,7 +4034,7 @@ COMPAT_SYSCALL_DEFINE3(sigaction, int, sig,
         compat_uptr_t handler, restorer;
 
         if (act) {
-                if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
+                if (!access_ok(act, sizeof(*act)) ||
                     __get_user(handler, &act->sa_handler) ||
                     __get_user(restorer, &act->sa_restorer) ||
                     __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
@@ -4052,7 +4052,7 @@ COMPAT_SYSCALL_DEFINE3(sigaction, int, sig,
         ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
 
         if (!ret && oact) {
-                if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
+                if (!access_ok(oact, sizeof(*oact)) ||
                     __put_user(ptr_to_compat(old_ka.sa.sa_handler),
                                &oact->sa_handler) ||
                     __put_user(ptr_to_compat(old_ka.sa.sa_restorer),
diff --git a/kernel/sys.c b/kernel/sys.c
index 64b5a230f38d..a48cbf1414b8 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -2627,7 +2627,7 @@ COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info)
                 s.freehigh >>= bitcount;
         }
 
-        if (!access_ok(VERIFY_WRITE, info, sizeof(struct compat_sysinfo)) ||
+        if (!access_ok(info, sizeof(struct compat_sysinfo)) ||
             __put_user(s.uptime, &info->uptime) ||
             __put_user(s.loads[0], &info->loads[0]) ||
             __put_user(s.loads[1], &info->loads[1]) ||
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 9ddb6fddb4e0..8b068adb9da1 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -170,7 +170,7 @@ BPF_CALL_3(bpf_probe_write_user, void *, unsafe_ptr, const void *, src,
                 return -EPERM;
         if (unlikely(uaccess_kernel()))
                 return -EPERM;
-        if (!access_ok(VERIFY_WRITE, unsafe_ptr, size))
+        if (!access_ok(unsafe_ptr, size))
                 return -EPERM;
 
         return probe_kernel_write(unsafe_ptr, src, size);