diff mbox

[PULL,v2,03/24] linux-user: Use safe_syscall wrapper for fcntl

Message ID 435da5e7092aa54e12044b9401b42c4a9333c74d.1467138806.git.riku.voipio@linaro.org
State New
Headers show

Commit Message

Riku Voipio June 28, 2016, 7:12 p.m. UTC 
From: Peter Maydell <peter.maydell@linaro.org>

Use the safe_syscall wrapper for fcntl. This is straightforward now
that we always use 'struct fcntl64' on the host, as we don't need
to select whether to call the host's fcntl64 or fcntl syscall
(a detail that the libc previously hid for us).

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>
---
 linux-user/syscall.c | 34 +++++++++++++++++++++++-----------
 1 file changed, 23 insertions(+), 11 deletions(-)

Comments

Laurent Vivier July 12, 2018, 7:18 a.m. UTC | #1 
Le 28/06/2016 à 21:12, riku.voipio@linaro.org a écrit :
> From: Peter Maydell <peter.maydell@linaro.org>
> 
> Use the safe_syscall wrapper for fcntl. This is straightforward now
> that we always use 'struct fcntl64' on the host, as we don't need
> to select whether to call the host's fcntl64 or fcntl syscall
> (a detail that the libc previously hid for us).
> 
> 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>
> ---
>  linux-user/syscall.c | 34 +++++++++++++++++++++++-----------
>  1 file changed, 23 insertions(+), 11 deletions(-)
...
> @@ -10252,7 +10264,7 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
>              if (ret) {
>                  break;
>              }
> -            ret = get_errno(fcntl(arg1, cmd, &fl));
> +            ret = get_errno(safe_fcntl(arg1, cmd, &fl));
>  	    break;
>          default:
>              ret = do_fcntl(arg1, arg2, arg3);
> 

Peter,

435da5e709 linux-user: Use safe_syscall wrapper for fcntl

do you remember why you only convert to safe_fcntl() the
TARGET_F_SETLK64 and TARGET_F_SETLKW64 cases and not the
TARGET_F_GETLK64 one (in TARGET_NR_fcntl64)?

Thanks,
Laurent
Peter Maydell July 12, 2018, 8:41 a.m. UTC | #2 
On 12 July 2018 at 08:18, Laurent Vivier <laurent@vivier.eu> wrote:
> Le 28/06/2016 à 21:12, riku.voipio@linaro.org a écrit :
>> From: Peter Maydell <peter.maydell@linaro.org>
>>
>> Use the safe_syscall wrapper for fcntl. This is straightforward now
>> that we always use 'struct fcntl64' on the host, as we don't need
>> to select whether to call the host's fcntl64 or fcntl syscall
>> (a detail that the libc previously hid for us).
>>
>> 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>
>> ---
>>  linux-user/syscall.c | 34 +++++++++++++++++++++++-----------
>>  1 file changed, 23 insertions(+), 11 deletions(-)
> ...
>> @@ -10252,7 +10264,7 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
>>              if (ret) {
>>                  break;
>>              }
>> -            ret = get_errno(fcntl(arg1, cmd, &fl));
>> +            ret = get_errno(safe_fcntl(arg1, cmd, &fl));
>>           break;
>>          default:
>>              ret = do_fcntl(arg1, arg2, arg3);
>>
>
> Peter,
>
> 435da5e709 linux-user: Use safe_syscall wrapper for fcntl
>
> do you remember why you only convert to safe_fcntl() the
> TARGET_F_SETLK64 and TARGET_F_SETLKW64 cases and not the
> TARGET_F_GETLK64 one (in TARGET_NR_fcntl64)?

I don't recall; I probably just missed that one. I don't
see any reason why it shouldn't be using safe_fcntl().

thanks
-- PMM
diff mbox

Patch

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 5c0d111..3dfaea9 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -783,6 +783,16 @@  safe_syscall5(int, mq_timedreceive, int, mqdes, char *, msg_ptr,
  * the libc function.
  */
 #define safe_ioctl(...) safe_syscall(__NR_ioctl, __VA_ARGS__)
+/* Similarly for fcntl. Note that callers must always:
+ *  pass the F_GETLK64 etc constants rather than the unsuffixed F_GETLK
+ *  use the flock64 struct rather than unsuffixed flock
+ * This will then work and use a 64-bit offset for both 32-bit and 64-bit hosts.
+ */
+#ifdef __NR_fcntl64
+#define safe_fcntl(...) safe_syscall(__NR_fcntl64, __VA_ARGS__)
+#else
+#define safe_fcntl(...) safe_syscall(__NR_fcntl, __VA_ARGS__)
+#endif
 
 static inline int host_to_target_sock_type(int host_type)
 {
@@ -5740,7 +5750,7 @@  static abi_long do_fcntl(int fd, int cmd, abi_ulong arg)
         if (ret) {
             return ret;
         }
-        ret = get_errno(fcntl(fd, host_cmd, &fl64));
+        ret = get_errno(safe_fcntl(fd, host_cmd, &fl64));
         if (ret == 0) {
             ret = copy_to_user_flock(arg, &fl64);
         }
@@ -5752,7 +5762,7 @@  static abi_long do_fcntl(int fd, int cmd, abi_ulong arg)
         if (ret) {
             return ret;
         }
-        ret = get_errno(fcntl(fd, host_cmd, &fl64));
+        ret = get_errno(safe_fcntl(fd, host_cmd, &fl64));
         break;
 
     case TARGET_F_GETLK64:
@@ -5760,7 +5770,7 @@  static abi_long do_fcntl(int fd, int cmd, abi_ulong arg)
         if (ret) {
             return ret;
         }
-        ret = get_errno(fcntl(fd, host_cmd, &fl64));
+        ret = get_errno(safe_fcntl(fd, host_cmd, &fl64));
         if (ret == 0) {
             ret = copy_to_user_flock64(arg, &fl64);
         }
@@ -5771,23 +5781,25 @@  static abi_long do_fcntl(int fd, int cmd, abi_ulong arg)
         if (ret) {
             return ret;
         }
-        ret = get_errno(fcntl(fd, host_cmd, &fl64));
+        ret = get_errno(safe_fcntl(fd, host_cmd, &fl64));
         break;
 
     case TARGET_F_GETFL:
-        ret = get_errno(fcntl(fd, host_cmd, arg));
+        ret = get_errno(safe_fcntl(fd, host_cmd, arg));
         if (ret >= 0) {
             ret = host_to_target_bitmask(ret, fcntl_flags_tbl);
         }
         break;
 
     case TARGET_F_SETFL:
-        ret = get_errno(fcntl(fd, host_cmd, target_to_host_bitmask(arg, fcntl_flags_tbl)));
+        ret = get_errno(safe_fcntl(fd, host_cmd,
+                                   target_to_host_bitmask(arg,
+                                                          fcntl_flags_tbl)));
         break;
 
 #ifdef F_GETOWN_EX
     case TARGET_F_GETOWN_EX:
-        ret = get_errno(fcntl(fd, host_cmd, &fox));
+        ret = get_errno(safe_fcntl(fd, host_cmd, &fox));
         if (ret >= 0) {
             if (!lock_user_struct(VERIFY_WRITE, target_fox, arg, 0))
                 return -TARGET_EFAULT;
@@ -5805,7 +5817,7 @@  static abi_long do_fcntl(int fd, int cmd, abi_ulong arg)
         fox.type = tswap32(target_fox->type);
         fox.pid = tswap32(target_fox->pid);
         unlock_user_struct(target_fox, arg, 0);
-        ret = get_errno(fcntl(fd, host_cmd, &fox));
+        ret = get_errno(safe_fcntl(fd, host_cmd, &fox));
         break;
 #endif
 
@@ -5815,11 +5827,11 @@  static abi_long do_fcntl(int fd, int cmd, abi_ulong arg)
     case TARGET_F_GETSIG:
     case TARGET_F_SETLEASE:
     case TARGET_F_GETLEASE:
-        ret = get_errno(fcntl(fd, host_cmd, arg));
+        ret = get_errno(safe_fcntl(fd, host_cmd, arg));
         break;
 
     default:
-        ret = get_errno(fcntl(fd, cmd, arg));
+        ret = get_errno(safe_fcntl(fd, cmd, arg));
         break;
     }
     return ret;
@@ -10252,7 +10264,7 @@  abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
             if (ret) {
                 break;
             }
-            ret = get_errno(fcntl(arg1, cmd, &fl));
+            ret = get_errno(safe_fcntl(arg1, cmd, &fl));
 	    break;
         default:
             ret = do_fcntl(arg1, arg2, arg3);