mirror of
https://github.com/xemu-project/xemu.git
synced 2024-11-27 13:30:52 +00:00
3d5e2b4f26
We are not currently bounding the search to the 1024 bytes that we allocated, possibly overrunning the buffer. Use softmmu_strlen_user to find the length and allocate the correct size from the beginning. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
92 lines
2.3 KiB
C
92 lines
2.3 KiB
C
/*
|
|
* Helper routines to provide target memory access for semihosting
|
|
* syscalls in system emulation mode.
|
|
*
|
|
* Copyright (c) 2007 CodeSourcery.
|
|
*
|
|
* This code is licensed under the GPL
|
|
*/
|
|
|
|
#include "qemu/osdep.h"
|
|
#include "exec/exec-all.h"
|
|
#include "semihosting/softmmu-uaccess.h"
|
|
|
|
void *softmmu_lock_user(CPUArchState *env, target_ulong addr,
|
|
target_ulong len, bool copy)
|
|
{
|
|
void *p = malloc(len);
|
|
if (p && copy) {
|
|
if (cpu_memory_rw_debug(env_cpu(env), addr, p, len, 0)) {
|
|
free(p);
|
|
p = NULL;
|
|
}
|
|
}
|
|
return p;
|
|
}
|
|
|
|
ssize_t softmmu_strlen_user(CPUArchState *env, target_ulong addr)
|
|
{
|
|
int mmu_idx = cpu_mmu_index(env, false);
|
|
size_t len = 0;
|
|
|
|
while (1) {
|
|
size_t left_in_page;
|
|
int flags;
|
|
void *h;
|
|
|
|
/* Find the number of bytes remaining in the page. */
|
|
left_in_page = TARGET_PAGE_SIZE - (addr & ~TARGET_PAGE_MASK);
|
|
|
|
flags = probe_access_flags(env, addr, MMU_DATA_LOAD,
|
|
mmu_idx, true, &h, 0);
|
|
if (flags & TLB_INVALID_MASK) {
|
|
return -1;
|
|
}
|
|
if (flags & TLB_MMIO) {
|
|
do {
|
|
uint8_t c;
|
|
if (cpu_memory_rw_debug(env_cpu(env), addr, &c, 1, 0)) {
|
|
return -1;
|
|
}
|
|
if (c == 0) {
|
|
return len;
|
|
}
|
|
addr++;
|
|
len++;
|
|
if (len > INT32_MAX) {
|
|
return -1;
|
|
}
|
|
} while (--left_in_page != 0);
|
|
} else {
|
|
char *p = memchr(h, 0, left_in_page);
|
|
if (p) {
|
|
len += p - (char *)h;
|
|
return len <= INT32_MAX ? (ssize_t)len : -1;
|
|
}
|
|
addr += left_in_page;
|
|
len += left_in_page;
|
|
if (len > INT32_MAX) {
|
|
return -1;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
char *softmmu_lock_user_string(CPUArchState *env, target_ulong addr)
|
|
{
|
|
ssize_t len = softmmu_strlen_user(env, addr);
|
|
if (len < 0) {
|
|
return NULL;
|
|
}
|
|
return softmmu_lock_user(env, addr, len + 1, true);
|
|
}
|
|
|
|
void softmmu_unlock_user(CPUArchState *env, void *p,
|
|
target_ulong addr, target_ulong len)
|
|
{
|
|
if (len) {
|
|
cpu_memory_rw_debug(env_cpu(env), addr, p, len, 1);
|
|
}
|
|
free(p);
|
|
}
|