fuse: conditionally fill kstat in fuse_do_statx()

The code path

fuse_update_attributes
    fuse_update_get_attr
        fuse_do_statx

has the risk to use a NULL pointer for struct kstat *stat, although current
callers of fuse_update_attributes() only set request_mask to values that
will trigger the call of fuse_do_getattr(), which already handles the NULL
pointer.  Future updates might miss that fuse_do_statx() does not handle it
it is safer to add a condition already right now.

Signed-off-by: Bernd Schubert <bschubert@ddn.com>
Fixes: d3045530bdd2 ("fuse: implement statx")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
This commit is contained in:
Bernd Schubert 2023-08-24 00:33:45 +02:00 committed by Miklos Szeredi
parent 7d875e6685
commit f73016b63b

View File

@ -1219,11 +1219,14 @@ static int fuse_do_statx(struct inode *inode, struct file *file,
fuse_change_attributes(inode, &attr, &outarg.stat,
ATTR_TIMEOUT(&outarg), attr_version);
}
stat->result_mask = sx->mask & (STATX_BASIC_STATS | STATX_BTIME);
stat->btime.tv_sec = sx->btime.tv_sec;
stat->btime.tv_nsec = min_t(u32, sx->btime.tv_nsec, NSEC_PER_SEC - 1);
fuse_fillattr(inode, &attr, stat);
stat->result_mask |= STATX_TYPE;
if (stat) {
stat->result_mask = sx->mask & (STATX_BASIC_STATS | STATX_BTIME);
stat->btime.tv_sec = sx->btime.tv_sec;
stat->btime.tv_nsec = min_t(u32, sx->btime.tv_nsec, NSEC_PER_SEC - 1);
fuse_fillattr(inode, &attr, stat);
stat->result_mask |= STATX_TYPE;
}
return 0;
}