s390/compat: fix compat_sys_statfs() memory corruption
The f_spare field within struct compat_statfs is four bytes larger
than within the native 31 bit struct statfs.
compat_sys_statfs() clears the f_spare field in user space which
means that in compat mode four bytes that are behind the user space
supplied struct compat_statfs will be corrupted (zeroed).
According to Thomas Gleixner's Linux 2.6 history tree this bug is
present since v2.5.74
87880da124 "[PATCH] s390: 31 bit compat.".
So it get's fixed shortly before its 10th anniversary. Tough luck.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
projects / ~andy / linux / commit