qemu/target-mips/mips-semi.c
Leon Alrae 26e7e982b2 target-mips: fix resource leak reported by Coverity
UHI assert and link operations call lock_user_string() twice to obtain two
strings pointed by gpr[4] and gpr[5]. If the second lock_user_string()
fails, then the first one won't get freed. Fix this by introducing another
macro responsible for obtaining two strings and handling allocation
failure.

Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
2015-07-15 14:07:25 +01:00

374 lines
10 KiB
C

/*
* Unified Hosting Interface syscalls.
*
* Copyright (c) 2015 Imagination Technologies
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include <sys/stat.h>
#include "cpu.h"
#include "exec/helper-proto.h"
#include "exec/softmmu-semi.h"
#include "exec/semihost.h"
typedef enum UHIOp {
UHI_exit = 1,
UHI_open = 2,
UHI_close = 3,
UHI_read = 4,
UHI_write = 5,
UHI_lseek = 6,
UHI_unlink = 7,
UHI_fstat = 8,
UHI_argc = 9,
UHI_argnlen = 10,
UHI_argn = 11,
UHI_plog = 13,
UHI_assert = 14,
UHI_pread = 19,
UHI_pwrite = 20,
UHI_link = 22
} UHIOp;
typedef struct UHIStat {
int16_t uhi_st_dev;
uint16_t uhi_st_ino;
uint32_t uhi_st_mode;
uint16_t uhi_st_nlink;
uint16_t uhi_st_uid;
uint16_t uhi_st_gid;
int16_t uhi_st_rdev;
uint64_t uhi_st_size;
uint64_t uhi_st_atime;
uint64_t uhi_st_spare1;
uint64_t uhi_st_mtime;
uint64_t uhi_st_spare2;
uint64_t uhi_st_ctime;
uint64_t uhi_st_spare3;
uint64_t uhi_st_blksize;
uint64_t uhi_st_blocks;
uint64_t uhi_st_spare4[2];
} UHIStat;
enum UHIOpenFlags {
UHIOpen_RDONLY = 0x0,
UHIOpen_WRONLY = 0x1,
UHIOpen_RDWR = 0x2,
UHIOpen_APPEND = 0x8,
UHIOpen_CREAT = 0x200,
UHIOpen_TRUNC = 0x400,
UHIOpen_EXCL = 0x800
};
/* Errno values taken from asm-mips/errno.h */
static uint16_t host_to_mips_errno[] = {
[ENAMETOOLONG] = 78,
#ifdef EOVERFLOW
[EOVERFLOW] = 79,
#endif
#ifdef ELOOP
[ELOOP] = 90,
#endif
};
static int errno_mips(int err)
{
if (err < 0 || err >= ARRAY_SIZE(host_to_mips_errno)) {
return EINVAL;
} else if (host_to_mips_errno[err]) {
return host_to_mips_errno[err];
} else {
return err;
}
}
static int copy_stat_to_target(CPUMIPSState *env, const struct stat *src,
target_ulong vaddr)
{
hwaddr len = sizeof(struct UHIStat);
UHIStat *dst = lock_user(VERIFY_WRITE, vaddr, len, 0);
if (!dst) {
errno = EFAULT;
return -1;
}
dst->uhi_st_dev = tswap16(src->st_dev);
dst->uhi_st_ino = tswap16(src->st_ino);
dst->uhi_st_mode = tswap32(src->st_mode);
dst->uhi_st_nlink = tswap16(src->st_nlink);
dst->uhi_st_uid = tswap16(src->st_uid);
dst->uhi_st_gid = tswap16(src->st_gid);
dst->uhi_st_rdev = tswap16(src->st_rdev);
dst->uhi_st_size = tswap64(src->st_size);
dst->uhi_st_atime = tswap64(src->st_atime);
dst->uhi_st_mtime = tswap64(src->st_mtime);
dst->uhi_st_ctime = tswap64(src->st_ctime);
#ifdef _WIN32
dst->uhi_st_blksize = 0;
dst->uhi_st_blocks = 0;
#else
dst->uhi_st_blksize = tswap64(src->st_blksize);
dst->uhi_st_blocks = tswap64(src->st_blocks);
#endif
unlock_user(dst, vaddr, len);
return 0;
}
static int get_open_flags(target_ulong target_flags)
{
int open_flags = 0;
if (target_flags & UHIOpen_RDWR) {
open_flags |= O_RDWR;
} else if (target_flags & UHIOpen_WRONLY) {
open_flags |= O_WRONLY;
} else {
open_flags |= O_RDONLY;
}
open_flags |= (target_flags & UHIOpen_APPEND) ? O_APPEND : 0;
open_flags |= (target_flags & UHIOpen_CREAT) ? O_CREAT : 0;
open_flags |= (target_flags & UHIOpen_TRUNC) ? O_TRUNC : 0;
open_flags |= (target_flags & UHIOpen_EXCL) ? O_EXCL : 0;
return open_flags;
}
static int write_to_file(CPUMIPSState *env, target_ulong fd, target_ulong vaddr,
target_ulong len, target_ulong offset)
{
int num_of_bytes;
void *dst = lock_user(VERIFY_READ, vaddr, len, 1);
if (!dst) {
errno = EFAULT;
return -1;
}
if (offset) {
#ifdef _WIN32
num_of_bytes = 0;
#else
num_of_bytes = pwrite(fd, dst, len, offset);
#endif
} else {
num_of_bytes = write(fd, dst, len);
}
unlock_user(dst, vaddr, 0);
return num_of_bytes;
}
static int read_from_file(CPUMIPSState *env, target_ulong fd,
target_ulong vaddr, target_ulong len,
target_ulong offset)
{
int num_of_bytes;
void *dst = lock_user(VERIFY_WRITE, vaddr, len, 0);
if (!dst) {
errno = EFAULT;
return -1;
}
if (offset) {
#ifdef _WIN32
num_of_bytes = 0;
#else
num_of_bytes = pread(fd, dst, len, offset);
#endif
} else {
num_of_bytes = read(fd, dst, len);
}
unlock_user(dst, vaddr, len);
return num_of_bytes;
}
static int copy_argn_to_target(CPUMIPSState *env, int arg_num,
target_ulong vaddr)
{
int strsize = strlen(semihosting_get_arg(arg_num)) + 1;
char *dst = lock_user(VERIFY_WRITE, vaddr, strsize, 0);
if (!dst) {
return -1;
}
strcpy(dst, semihosting_get_arg(arg_num));
unlock_user(dst, vaddr, strsize);
return 0;
}
#define GET_TARGET_STRING(p, addr) \
do { \
p = lock_user_string(addr); \
if (!p) { \
gpr[2] = -1; \
gpr[3] = EFAULT; \
goto uhi_done; \
} \
} while (0)
#define GET_TARGET_STRINGS_2(p, addr, p2, addr2) \
do { \
p = lock_user_string(addr); \
if (!p) { \
gpr[2] = -1; \
gpr[3] = EFAULT; \
goto uhi_done; \
} \
p2 = lock_user_string(addr2); \
if (!p2) { \
unlock_user(p, addr, 0); \
gpr[2] = -1; \
gpr[3] = EFAULT; \
goto uhi_done; \
} \
} while (0)
#define FREE_TARGET_STRING(p, gpr) \
do { \
unlock_user(p, gpr, 0); \
} while (0)
void helper_do_semihosting(CPUMIPSState *env)
{
target_ulong *gpr = env->active_tc.gpr;
const UHIOp op = gpr[25];
char *p, *p2;
switch (op) {
case UHI_exit:
qemu_log("UHI(%d): exit(%d)\n", op, (int)gpr[4]);
exit(gpr[4]);
case UHI_open:
GET_TARGET_STRING(p, gpr[4]);
if (!strcmp("/dev/stdin", p)) {
gpr[2] = 0;
} else if (!strcmp("/dev/stdout", p)) {
gpr[2] = 1;
} else if (!strcmp("/dev/stderr", p)) {
gpr[2] = 2;
} else {
gpr[2] = open(p, get_open_flags(gpr[5]), gpr[6]);
gpr[3] = errno_mips(errno);
}
FREE_TARGET_STRING(p, gpr[4]);
break;
case UHI_close:
if (gpr[4] < 3) {
/* ignore closing stdin/stdout/stderr */
gpr[2] = 0;
goto uhi_done;
}
gpr[2] = close(gpr[4]);
gpr[3] = errno_mips(errno);
break;
case UHI_read:
gpr[2] = read_from_file(env, gpr[4], gpr[5], gpr[6], 0);
gpr[3] = errno_mips(errno);
break;
case UHI_write:
gpr[2] = write_to_file(env, gpr[4], gpr[5], gpr[6], 0);
gpr[3] = errno_mips(errno);
break;
case UHI_lseek:
gpr[2] = lseek(gpr[4], gpr[5], gpr[6]);
gpr[3] = errno_mips(errno);
break;
case UHI_unlink:
GET_TARGET_STRING(p, gpr[4]);
gpr[2] = remove(p);
gpr[3] = errno_mips(errno);
FREE_TARGET_STRING(p, gpr[4]);
break;
case UHI_fstat:
{
struct stat sbuf;
memset(&sbuf, 0, sizeof(sbuf));
gpr[2] = fstat(gpr[4], &sbuf);
gpr[3] = errno_mips(errno);
if (gpr[2]) {
goto uhi_done;
}
gpr[2] = copy_stat_to_target(env, &sbuf, gpr[5]);
gpr[3] = errno_mips(errno);
}
break;
case UHI_argc:
gpr[2] = semihosting_get_argc();
break;
case UHI_argnlen:
if (gpr[4] >= semihosting_get_argc()) {
gpr[2] = -1;
goto uhi_done;
}
gpr[2] = strlen(semihosting_get_arg(gpr[4]));
break;
case UHI_argn:
if (gpr[4] >= semihosting_get_argc()) {
gpr[2] = -1;
goto uhi_done;
}
gpr[2] = copy_argn_to_target(env, gpr[4], gpr[5]);
break;
case UHI_plog:
GET_TARGET_STRING(p, gpr[4]);
p2 = strstr(p, "%d");
if (p2) {
int char_num = p2 - p;
char *buf = g_malloc(char_num + 1);
strncpy(buf, p, char_num);
buf[char_num] = '\0';
gpr[2] = printf("%s%d%s", buf, (int)gpr[5], p2 + 2);
g_free(buf);
} else {
gpr[2] = printf("%s", p);
}
FREE_TARGET_STRING(p, gpr[4]);
break;
case UHI_assert:
GET_TARGET_STRINGS_2(p, gpr[4], p2, gpr[5]);
printf("assertion '");
printf("\"%s\"", p);
printf("': file \"%s\", line %d\n", p2, (int)gpr[6]);
FREE_TARGET_STRING(p2, gpr[5]);
FREE_TARGET_STRING(p, gpr[4]);
abort();
break;
case UHI_pread:
gpr[2] = read_from_file(env, gpr[4], gpr[5], gpr[6], gpr[7]);
gpr[3] = errno_mips(errno);
break;
case UHI_pwrite:
gpr[2] = write_to_file(env, gpr[4], gpr[5], gpr[6], gpr[7]);
gpr[3] = errno_mips(errno);
break;
#ifndef _WIN32
case UHI_link:
GET_TARGET_STRINGS_2(p, gpr[4], p2, gpr[5]);
gpr[2] = link(p, p2);
gpr[3] = errno_mips(errno);
FREE_TARGET_STRING(p2, gpr[5]);
FREE_TARGET_STRING(p, gpr[4]);
break;
#endif
default:
fprintf(stderr, "Unknown UHI operation %d\n", op);
abort();
}
uhi_done:
return;
}