openkylin
/
qemu
mirror of https://gitee.com/openkylin/qemu.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

linux-user: Use __get_user() and __put_user() to handle structs in do_fcntl() 

Use the __get_user() and __put_user() to handle reading and writing the
guest structures in do_ioctl(). This has two benefits:
 * avoids possible errors due to misaligned guest pointers
 * correctly sign extends signed fields (like l_start in struct flock)
   which might be different sizes between guest and host

To do this we abstract out into copy_from/to_user functions. We
also standardize on always using host flock64 and the F_GETLK64
etc flock commands, as this means we always have 64 bit offsets
whether the host is 64-bit or 32-bit and we don't need to support
conversion to both host struct flock and struct flock64.

In passing we fix errors in converting l_type from the host to
the target (where we were doing a byteswap of the host value
before trying to do the convert-bitmasks operation rather than
otherwise, and inexplicably shifting left by 1); these were
accidentally left over when the original simple "just shift by 1"
arm<->x86 conversion of commit 43f238d was changed to the more
general scheme of using target_to_host_bitmask() functions in 2ba7f73.

[RV: fixed ifdef guard for eabi functions]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
This commit is contained in:
Peter Maydell 2016-06-13 11:22:05 +01:00 committed by Riku Voipio
parent 55d72a7eb3
commit 213d3e9ea2
1 changed files with 166 additions and 132 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

298
linux-user/syscall.c
View File

@ -5541,11 +5541,11 @@ static int target_to_host_fcntl_cmd(int cmd)
case TARGET_F_SETFL: case TARGET_F_SETFL:
return cmd; return cmd;
case TARGET_F_GETLK: case TARGET_F_GETLK:
return F_GETLK; return F_GETLK64;
case TARGET_F_SETLK: case TARGET_F_SETLK:
return F_SETLK; return F_SETLK64;
case TARGET_F_SETLKW: case TARGET_F_SETLKW:
return F_SETLKW; return F_SETLKW64;
case TARGET_F_GETOWN: case TARGET_F_GETOWN:
return F_GETOWN; return F_GETOWN;
case TARGET_F_SETOWN: case TARGET_F_SETOWN:
@ -5596,12 +5596,134 @@ static const bitmask_transtbl flock_tbl[] = {
{ 0, 0, 0, 0 } { 0, 0, 0, 0 }
}; };
static inline abi_long copy_from_user_flock(struct flock64 *fl,
abi_ulong target_flock_addr)
{
struct target_flock *target_fl;
short l_type;
if (!lock_user_struct(VERIFY_READ, target_fl, target_flock_addr, 1)) {
return -TARGET_EFAULT;
}
__get_user(l_type, &target_fl->l_type);
fl->l_type = target_to_host_bitmask(l_type, flock_tbl);
__get_user(fl->l_whence, &target_fl->l_whence);
__get_user(fl->l_start, &target_fl->l_start);
__get_user(fl->l_len, &target_fl->l_len);
__get_user(fl->l_pid, &target_fl->l_pid);
unlock_user_struct(target_fl, target_flock_addr, 0);
return 0;
}
static inline abi_long copy_to_user_flock(abi_ulong target_flock_addr,
const struct flock64 *fl)
{
struct target_flock *target_fl;
short l_type;
if (!lock_user_struct(VERIFY_WRITE, target_fl, target_flock_addr, 0)) {
return -TARGET_EFAULT;
}
l_type = host_to_target_bitmask(fl->l_type, flock_tbl);
__put_user(l_type, &target_fl->l_type);
__put_user(fl->l_whence, &target_fl->l_whence);
__put_user(fl->l_start, &target_fl->l_start);
__put_user(fl->l_len, &target_fl->l_len);
__put_user(fl->l_pid, &target_fl->l_pid);
unlock_user_struct(target_fl, target_flock_addr, 1);
return 0;
}
typedef abi_long from_flock64_fn(struct flock64 *fl, abi_ulong target_addr);
typedef abi_long to_flock64_fn(abi_ulong target_addr, const struct flock64 *fl);
#if defined(TARGET_ARM) && TARGET_ABI_BITS == 32
static inline abi_long copy_from_user_eabi_flock64(struct flock64 *fl,
abi_ulong target_flock_addr)
{
struct target_eabi_flock64 *target_fl;
short l_type;
if (!lock_user_struct(VERIFY_READ, target_fl, target_flock_addr, 1)) {
return -TARGET_EFAULT;
}
__get_user(l_type, &target_fl->l_type);
fl->l_type = target_to_host_bitmask(l_type, flock_tbl);
__get_user(fl->l_whence, &target_fl->l_whence);
__get_user(fl->l_start, &target_fl->l_start);
__get_user(fl->l_len, &target_fl->l_len);
__get_user(fl->l_pid, &target_fl->l_pid);
unlock_user_struct(target_fl, target_flock_addr, 0);
return 0;
}
static inline abi_long copy_to_user_eabi_flock64(abi_ulong target_flock_addr,
const struct flock64 *fl)
{
struct target_eabi_flock64 *target_fl;
short l_type;
if (!lock_user_struct(VERIFY_WRITE, target_fl, target_flock_addr, 0)) {
return -TARGET_EFAULT;
}
l_type = host_to_target_bitmask(fl->l_type, flock_tbl);
__put_user(l_type, &target_fl->l_type);
__put_user(fl->l_whence, &target_fl->l_whence);
__put_user(fl->l_start, &target_fl->l_start);
__put_user(fl->l_len, &target_fl->l_len);
__put_user(fl->l_pid, &target_fl->l_pid);
unlock_user_struct(target_fl, target_flock_addr, 1);
return 0;
}
#endif
static inline abi_long copy_from_user_flock64(struct flock64 *fl,
abi_ulong target_flock_addr)
{
struct target_flock64 *target_fl;
short l_type;
if (!lock_user_struct(VERIFY_READ, target_fl, target_flock_addr, 1)) {
return -TARGET_EFAULT;
}
__get_user(l_type, &target_fl->l_type);
fl->l_type = target_to_host_bitmask(l_type, flock_tbl);
__get_user(fl->l_whence, &target_fl->l_whence);
__get_user(fl->l_start, &target_fl->l_start);
__get_user(fl->l_len, &target_fl->l_len);
__get_user(fl->l_pid, &target_fl->l_pid);
unlock_user_struct(target_fl, target_flock_addr, 0);
return 0;
}
static inline abi_long copy_to_user_flock64(abi_ulong target_flock_addr,
const struct flock64 *fl)
{
struct target_flock64 *target_fl;
short l_type;
if (!lock_user_struct(VERIFY_WRITE, target_fl, target_flock_addr, 0)) {
return -TARGET_EFAULT;
}
l_type = host_to_target_bitmask(fl->l_type, flock_tbl);
__put_user(l_type, &target_fl->l_type);
__put_user(fl->l_whence, &target_fl->l_whence);
__put_user(fl->l_start, &target_fl->l_start);
__put_user(fl->l_len, &target_fl->l_len);
__put_user(fl->l_pid, &target_fl->l_pid);
unlock_user_struct(target_fl, target_flock_addr, 1);
return 0;
}
static abi_long do_fcntl(int fd, int cmd, abi_ulong arg) static abi_long do_fcntl(int fd, int cmd, abi_ulong arg)
{ {
struct flock fl;
struct target_flock *target_fl;
struct flock64 fl64; struct flock64 fl64;
struct target_flock64 *target_fl64;
#ifdef F_GETOWN_EX #ifdef F_GETOWN_EX
struct f_owner_ex fox; struct f_owner_ex fox;
struct target_f_owner_ex *target_fox; struct target_f_owner_ex *target_fox;
@ -5614,77 +5736,41 @@ static abi_long do_fcntl(int fd, int cmd, abi_ulong arg)
switch(cmd) { switch(cmd) {
case TARGET_F_GETLK: case TARGET_F_GETLK:
if (!lock_user_struct(VERIFY_READ, target_fl, arg, 1)) ret = copy_from_user_flock(&fl64, arg);
return -TARGET_EFAULT; if (ret) {
fl.l_type = return ret;
target_to_host_bitmask(tswap16(target_fl->l_type), flock_tbl); }
fl.l_whence = tswap16(target_fl->l_whence); ret = get_errno(fcntl(fd, host_cmd, &fl64));
fl.l_start = tswapal(target_fl->l_start);
fl.l_len = tswapal(target_fl->l_len);
fl.l_pid = tswap32(target_fl->l_pid);
unlock_user_struct(target_fl, arg, 0);
ret = get_errno(fcntl(fd, host_cmd, &fl));
if (ret == 0) { if (ret == 0) {
if (!lock_user_struct(VERIFY_WRITE, target_fl, arg, 0)) ret = copy_to_user_flock(arg, &fl64);
return -TARGET_EFAULT;
target_fl->l_type =
host_to_target_bitmask(tswap16(fl.l_type), flock_tbl);
target_fl->l_whence = tswap16(fl.l_whence);
target_fl->l_start = tswapal(fl.l_start);
target_fl->l_len = tswapal(fl.l_len);
target_fl->l_pid = tswap32(fl.l_pid);
unlock_user_struct(target_fl, arg, 1);
} }
break; break;
case TARGET_F_SETLK: case TARGET_F_SETLK:
case TARGET_F_SETLKW: case TARGET_F_SETLKW:
if (!lock_user_struct(VERIFY_READ, target_fl, arg, 1)) ret = copy_from_user_flock(&fl64, arg);
return -TARGET_EFAULT; if (ret) {
fl.l_type = return ret;
target_to_host_bitmask(tswap16(target_fl->l_type), flock_tbl); }
fl.l_whence = tswap16(target_fl->l_whence); ret = get_errno(fcntl(fd, host_cmd, &fl64));
fl.l_start = tswapal(target_fl->l_start);
fl.l_len = tswapal(target_fl->l_len);
fl.l_pid = tswap32(target_fl->l_pid);
unlock_user_struct(target_fl, arg, 0);
ret = get_errno(fcntl(fd, host_cmd, &fl));
break; break;
case TARGET_F_GETLK64: case TARGET_F_GETLK64:
if (!lock_user_struct(VERIFY_READ, target_fl64, arg, 1)) ret = copy_from_user_flock64(&fl64, arg);
return -TARGET_EFAULT; if (ret) {
fl64.l_type = return ret;
target_to_host_bitmask(tswap16(target_fl64->l_type), flock_tbl) >> 1; }
fl64.l_whence = tswap16(target_fl64->l_whence);
fl64.l_start = tswap64(target_fl64->l_start);
fl64.l_len = tswap64(target_fl64->l_len);
fl64.l_pid = tswap32(target_fl64->l_pid);
unlock_user_struct(target_fl64, arg, 0);
ret = get_errno(fcntl(fd, host_cmd, &fl64)); ret = get_errno(fcntl(fd, host_cmd, &fl64));
if (ret == 0) { if (ret == 0) {
if (!lock_user_struct(VERIFY_WRITE, target_fl64, arg, 0)) ret = copy_to_user_flock64(arg, &fl64);
return -TARGET_EFAULT;
target_fl64->l_type =
host_to_target_bitmask(tswap16(fl64.l_type), flock_tbl) >> 1;
target_fl64->l_whence = tswap16(fl64.l_whence);
target_fl64->l_start = tswap64(fl64.l_start);
target_fl64->l_len = tswap64(fl64.l_len);
target_fl64->l_pid = tswap32(fl64.l_pid);
unlock_user_struct(target_fl64, arg, 1);
} }
break; break;
case TARGET_F_SETLK64: case TARGET_F_SETLK64:
case TARGET_F_SETLKW64: case TARGET_F_SETLKW64:
if (!lock_user_struct(VERIFY_READ, target_fl64, arg, 1)) ret = copy_from_user_flock64(&fl64, arg);
return -TARGET_EFAULT; if (ret) {
fl64.l_type = return ret;
target_to_host_bitmask(tswap16(target_fl64->l_type), flock_tbl) >> 1; }
fl64.l_whence = tswap16(target_fl64->l_whence);
fl64.l_start = tswap64(target_fl64->l_start);
fl64.l_len = tswap64(target_fl64->l_len);
fl64.l_pid = tswap32(target_fl64->l_pid);
unlock_user_struct(target_fl64, arg, 0);
ret = get_errno(fcntl(fd, host_cmd, &fl64)); ret = get_errno(fcntl(fd, host_cmd, &fl64));
break; break;
@ -10132,9 +10218,14 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
{ {
int cmd; int cmd;
struct flock64 fl; struct flock64 fl;
struct target_flock64 *target_fl; from_flock64_fn *copyfrom = copy_from_user_flock64;
to_flock64_fn *copyto = copy_to_user_flock64;
#ifdef TARGET_ARM #ifdef TARGET_ARM
struct target_eabi_flock64 *target_efl; if (((CPUARMState *)cpu_env)->eabi) {
copyfrom = copy_from_user_eabi_flock64;
copyto = copy_to_user_eabi_flock64;
}
#endif #endif
cmd = target_to_host_fcntl_cmd(arg2); cmd = target_to_host_fcntl_cmd(arg2);
@ -10145,78 +10236,21 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
switch(arg2) { switch(arg2) {
case TARGET_F_GETLK64: case TARGET_F_GETLK64:
#ifdef TARGET_ARM ret = copyfrom(&fl, arg3);
if (((CPUARMState *)cpu_env)->eabi) { if (ret) {
if (!lock_user_struct(VERIFY_READ, target_efl, arg3, 1)) break;
goto efault;
fl.l_type = tswap16(target_efl->l_type);
fl.l_whence = tswap16(target_efl->l_whence);
fl.l_start = tswap64(target_efl->l_start);
fl.l_len = tswap64(target_efl->l_len);
fl.l_pid = tswap32(target_efl->l_pid);
unlock_user_struct(target_efl, arg3, 0);
} else
#endif
{
if (!lock_user_struct(VERIFY_READ, target_fl, arg3, 1))
goto efault;
fl.l_type = tswap16(target_fl->l_type);
fl.l_whence = tswap16(target_fl->l_whence);
fl.l_start = tswap64(target_fl->l_start);
fl.l_len = tswap64(target_fl->l_len);
fl.l_pid = tswap32(target_fl->l_pid);
unlock_user_struct(target_fl, arg3, 0);
} }
ret = get_errno(fcntl(arg1, cmd, &fl)); ret = get_errno(fcntl(arg1, cmd, &fl));
if (ret == 0) { if (ret == 0) {
#ifdef TARGET_ARM ret = copyto(arg3, &fl);
if (((CPUARMState *)cpu_env)->eabi) { }
if (!lock_user_struct(VERIFY_WRITE, target_efl, arg3, 0))
goto efault;
target_efl->l_type = tswap16(fl.l_type);
target_efl->l_whence = tswap16(fl.l_whence);
target_efl->l_start = tswap64(fl.l_start);
target_efl->l_len = tswap64(fl.l_len);
target_efl->l_pid = tswap32(fl.l_pid);
unlock_user_struct(target_efl, arg3, 1);
} else
#endif
{
if (!lock_user_struct(VERIFY_WRITE, target_fl, arg3, 0))
goto efault;
target_fl->l_type = tswap16(fl.l_type);
target_fl->l_whence = tswap16(fl.l_whence);
target_fl->l_start = tswap64(fl.l_start);
target_fl->l_len = tswap64(fl.l_len);
target_fl->l_pid = tswap32(fl.l_pid);
unlock_user_struct(target_fl, arg3, 1);
}
}
break; break;
case TARGET_F_SETLK64: case TARGET_F_SETLK64:
case TARGET_F_SETLKW64: case TARGET_F_SETLKW64:
#ifdef TARGET_ARM ret = copyfrom(&fl, arg3);
if (((CPUARMState *)cpu_env)->eabi) { if (ret) {
if (!lock_user_struct(VERIFY_READ, target_efl, arg3, 1)) break;
goto efault;
fl.l_type = tswap16(target_efl->l_type);
fl.l_whence = tswap16(target_efl->l_whence);
fl.l_start = tswap64(target_efl->l_start);
fl.l_len = tswap64(target_efl->l_len);
fl.l_pid = tswap32(target_efl->l_pid);
unlock_user_struct(target_efl, arg3, 0);
} else
#endif
{
if (!lock_user_struct(VERIFY_READ, target_fl, arg3, 1))
goto efault;
fl.l_type = tswap16(target_fl->l_type);
fl.l_whence = tswap16(target_fl->l_whence);
fl.l_start = tswap64(target_fl->l_start);
fl.l_len = tswap64(target_fl->l_len);
fl.l_pid = tswap32(target_fl->l_pid);
unlock_user_struct(target_fl, arg3, 0);
} }
ret = get_errno(fcntl(arg1, cmd, &fl)); ret = get_errno(fcntl(arg1, cmd, &fl));
break; break;