[PATCH] sound/oss/emu10k1: handle userspace copy errors
Propagate copy_to/from_user() errors back through callers.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/sound/oss/emu10k1/cardwi.c b/sound/oss/emu10k1/cardwi.c
index 8bbf44b..060d1be 100644
--- a/sound/oss/emu10k1/cardwi.c
+++ b/sound/oss/emu10k1/cardwi.c
@@ -304,11 +304,12 @@
}
}
-static void copy_block(u8 __user *dst, u8 * src, u32 str, u32 len, u8 cov)
+static int copy_block(u8 __user *dst, u8 * src, u32 str, u32 len, u8 cov)
{
- if (cov == 1)
- __copy_to_user(dst, src + str, len);
- else {
+ if (cov == 1) {
+ if (__copy_to_user(dst, src + str, len))
+ return -EFAULT;
+ } else {
u8 byte;
u32 i;
@@ -316,22 +317,26 @@
for (i = 0; i < len; i++) {
byte = src[2 * i] ^ 0x80;
- __copy_to_user(dst + i, &byte, 1);
+ if (__copy_to_user(dst + i, &byte, 1))
+ return -EFAULT;
}
}
+
+ return 0;
}
-void emu10k1_wavein_xferdata(struct wiinst *wiinst, u8 __user *data, u32 * size)
+int emu10k1_wavein_xferdata(struct wiinst *wiinst, u8 __user *data, u32 * size)
{
struct wavein_buffer *buffer = &wiinst->buffer;
u32 sizetocopy, sizetocopy_now, start;
unsigned long flags;
+ int ret;
sizetocopy = min_t(u32, buffer->size, *size);
*size = sizetocopy;
if (!sizetocopy)
- return;
+ return 0;
spin_lock_irqsave(&wiinst->lock, flags);
start = buffer->pos;
@@ -345,11 +350,17 @@
if (sizetocopy > sizetocopy_now) {
sizetocopy -= sizetocopy_now;
- copy_block(data, buffer->addr, start, sizetocopy_now, buffer->cov);
- copy_block(data + sizetocopy_now, buffer->addr, 0, sizetocopy, buffer->cov);
+ ret = copy_block(data, buffer->addr, start, sizetocopy_now,
+ buffer->cov);
+ if (ret == 0)
+ ret = copy_block(data + sizetocopy_now, buffer->addr, 0,
+ sizetocopy, buffer->cov);
} else {
- copy_block(data, buffer->addr, start, sizetocopy, buffer->cov);
+ ret = copy_block(data, buffer->addr, start, sizetocopy,
+ buffer->cov);
}
+
+ return ret;
}
void emu10k1_wavein_update(struct emu10k1_card *card, struct wiinst *wiinst)