Yaya48
cf256aa081
Upstream: https://gitlab.com/qemu-project/qemu.git Upstream-Commit: d2e570cc0f97b936902a5b1b86b73c0f5998b475
66 lines
1.7 KiB
C
66 lines
1.7 KiB
C
/* User memory access */
|
|
#include "qemu/osdep.h"
|
|
#include "qemu/cutils.h"
|
|
|
|
#include "qemu.h"
|
|
|
|
/* copy_from_user() and copy_to_user() are usually used to copy data
|
|
* buffers between the target and host. These internally perform
|
|
* locking/unlocking of the memory.
|
|
*/
|
|
abi_long copy_from_user(void *hptr, abi_ulong gaddr, size_t len)
|
|
{
|
|
abi_long ret = 0;
|
|
void *ghptr;
|
|
|
|
if ((ghptr = lock_user(VERIFY_READ, gaddr, len, 1))) {
|
|
memcpy(hptr, ghptr, len);
|
|
unlock_user(ghptr, gaddr, 0);
|
|
} else
|
|
ret = -TARGET_EFAULT;
|
|
|
|
return ret;
|
|
}
|
|
|
|
|
|
abi_long copy_to_user(abi_ulong gaddr, void *hptr, size_t len)
|
|
{
|
|
abi_long ret = 0;
|
|
void *ghptr;
|
|
|
|
if ((ghptr = lock_user(VERIFY_WRITE, gaddr, len, 0))) {
|
|
memcpy(ghptr, hptr, len);
|
|
unlock_user(ghptr, gaddr, len);
|
|
} else
|
|
ret = -TARGET_EFAULT;
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* Return the length of a string in target memory or -TARGET_EFAULT if
|
|
access error */
|
|
abi_long target_strlen(abi_ulong guest_addr1)
|
|
{
|
|
uint8_t *ptr;
|
|
abi_ulong guest_addr;
|
|
size_t max_len, len;
|
|
|
|
guest_addr = guest_addr1;
|
|
for (;;) {
|
|
max_len = TARGET_PAGE_SIZE - (guest_addr & ~TARGET_PAGE_MASK);
|
|
ptr = lock_user(VERIFY_READ, guest_addr, max_len, 1);
|
|
if (!ptr)
|
|
return -TARGET_EFAULT;
|
|
len = strnlen((const char *)ptr, max_len);
|
|
unlock_user(ptr, guest_addr, 0);
|
|
guest_addr += len;
|
|
/* we don't allow wrapping or integer overflow */
|
|
if (guest_addr == 0 ||
|
|
(guest_addr - guest_addr1) > 0x7fffffff)
|
|
return -TARGET_EFAULT;
|
|
if (len != max_len)
|
|
break;
|
|
}
|
|
return guest_addr - guest_addr1;
|
|
}
|