xiaomi-sm8450/android_kernel_xiaomi_sm8450
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fix abuses of ptrdiff_t

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Use of ptrdiff_t in places like

-                       if (!access_ok(VERIFY_WRITE, u_tmp->rx_buf, u_tmp->len))
+                       if (!access_ok(VERIFY_WRITE, (u8 __user *)
+                                               (ptrdiff_t) u_tmp->rx_buf,
+                                               u_tmp->len))

is wrong; for one thing, it's a bad C (it's what uintptr_t is for; in general
we are not even promised that ptrdiff_t is large enough to hold a pointer,
just enough to hold a difference between two pointers within the same object).
For another, it confuses the fsck out of sparse.

Use unsigned long or uintptr_t instead.  There are several places misusing
ptrdiff_t; fixed.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Al Viro
2007-10-29 05:11:28 +00:00
committed by Linus Torvalds
parent 0c7eb2eb80
commit 142956af52
5 changed files with 13 additions and 11 deletions
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6
drivers/spi/spidev.c
View File

@@ -184,14 +184,14 @@ static int spidev_message(struct spidev_data *spidev,
if (u_tmp->rx_buf) {
k_tmp->rx_buf = buf;
if (!access_ok(VERIFY_WRITE, (u8 __user *)
(ptrdiff_t) u_tmp->rx_buf,
(uintptr_t) u_tmp->rx_buf,
u_tmp->len))
goto done;
}
if (u_tmp->tx_buf) {
k_tmp->tx_buf = buf;
if (copy_from_user(buf, (const u8 __user *)
(ptrdiff_t) u_tmp->tx_buf,
(uintptr_t) u_tmp->tx_buf,
u_tmp->len))
goto done;
}
@@ -224,7 +224,7 @@ static int spidev_message(struct spidev_data *spidev,
for (n = n_xfers, u_tmp = u_xfers; n; n--, u_tmp++) {
if (u_tmp->rx_buf) {
if (__copy_to_user((u8 __user *)
(ptrdiff_t) u_tmp->rx_buf, buf,
(uintptr_t) u_tmp->rx_buf, buf,
u_tmp->len)) {
status = -EFAULT;
goto done;