On 2018-02-15 20:17, Laurent Vivier wrote:
Le 08/02/2018 à 10:56, Nageswara R Sastry a écrit :
On 2018-02-07 19:27, Laurent Vivier wrote:
Le 07/02/2018 à 10:49, [email protected] a écrit :
Hi,
This series failed build test on s390x host. Please find the details
below.
...
CC aarch64_be-linux-user/linux-user/syscall.o
In file included from
/var/tmp/patchew-tester-tmp-ewjgn083/src/linux-user/qemu.h:16:0,
from
/var/tmp/patchew-tester-tmp-ewjgn083/src/linux-user/syscall.c:118:
/var/tmp/patchew-tester-tmp-ewjgn083/src/linux-user/syscall.c: In
function ‘do_sendrecvmsg_locked’:
/var/tmp/patchew-tester-tmp-ewjgn083/src/linux-user/syscall_defs.h:308:61:
error: ‘tgt_len’ may be used uninitialized in this function
[-Werror=maybe-uninitialized]
#define TARGET_CMSG_LEN(len) (sizeof(struct target_cmsghdr) +
(len))
^
/var/tmp/patchew-tester-tmp-ewjgn083/src/linux-user/syscall.c:1797:13:
note:
‘tgt_len’ was declared here
int tgt_len, tgt_space;
^~~~~~~
it seems gcc disagrees with Coverity...
I think this should fixed like:
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 74378947f0..d7fbe334eb 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -1824,8 +1824,10 @@ static inline abi_long
host_to_target_cmsg(struct
target_msghdr *target_msgh,
tgt_len = sizeof(struct
target_timeval);
break;
default:
+ tgt_len = len;
break;
In my view this will result in assigning a wrong value to
‘tgt_len’ at
this ‘switch-case’ condition.
Instead looking at the option of initializing ‘tgt_len' to ‘0’.
According to the comment above the switch():
/* Payload types which need a different size of payload on
* the target must adjust tgt_len here.
*/
So "tgt_len" must be "len" by default, except if it needs to be
adjusted
(currently only for SO_TIMESTAMP), so I don't understand why it should
be set to "0".
Thanks,
Laurent
1814 switch (cmsg->cmsg_level) {
1815 case SOL_SOCKET:
1816 switch (cmsg->cmsg_type) {
1817 case SO_TIMESTAMP:
1818 tgt_len = sizeof(struct target_timeval);
1819 break;
1820 default:
1821 break;
1822 }
1823 default:
1824 tgt_len = len;
1825 break;
1826 }
If setting tgt_len = len at 1820 then it get set to 'case SOL_SOCKET{
switch (cmsg_type's default) }' This place am not sure assingn tgt_len
with len. To eliminate the gcc uninitialized error thought of
initializing with '0'.
--
Regards,
R.Nageswara Sastry
