From 1448c721e4fa2faf742029a0403b4b787fccb7fa Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Mon, 17 Oct 2011 13:40:02 -0700 Subject: compat: sync compat_stats with statfs. This was found by inspection while tracking a similar bug in compat_statfs64, that has been fixed in mainline since decemeber. - This fixes a bug where not all of the f_spare fields were cleared on mips and s390. - Add the f_flags field to struct compat_statfs - Copy f_flags to userspace in case someone cares. - Use __clear_user to copy the f_spare field to userspace to ensure that all of the elements of f_spare are cleared. On some architectures f_spare is has 5 ints and on some architectures f_spare only has 4 ints. Which makes the previous technique of clearing each int individually broken. I don't expect anyone actually uses the old statfs system call anymore but if they do let them benefit from having the compat and the native version working the same. Signed-off-by: Eric W. Biederman Signed-off-by: Christoph Hellwig --- fs/compat.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) (limited to 'fs') diff --git a/fs/compat.c b/fs/compat.c index 58b1da45989..0f1ab468fa2 100644 --- a/fs/compat.c +++ b/fs/compat.c @@ -247,11 +247,8 @@ static int put_compat_statfs(struct compat_statfs __user *ubuf, struct kstatfs * __put_user(kbuf->f_fsid.val[0], &ubuf->f_fsid.val[0]) || __put_user(kbuf->f_fsid.val[1], &ubuf->f_fsid.val[1]) || __put_user(kbuf->f_frsize, &ubuf->f_frsize) || - __put_user(0, &ubuf->f_spare[0]) || - __put_user(0, &ubuf->f_spare[1]) || - __put_user(0, &ubuf->f_spare[2]) || - __put_user(0, &ubuf->f_spare[3]) || - __put_user(0, &ubuf->f_spare[4])) + __put_user(kbuf->f_flags, &ubuf->f_flags) || + __clear_user(ubuf->f_spare, sizeof(ubuf->f_spare))) return -EFAULT; return 0; } -- cgit v1.2.3