From c7af63d62aba273554d6c8457e26c870ed207b40 Mon Sep 17 00:00:00 2001 From: Chunwei Chen Date: Thu, 2 Feb 2017 09:43:42 -0800 Subject: [PATCH] Fix write(2) returns zero bug from 933ec99 For generic_write_checks with 2 args, we can exit when it returns zero because it means count is zero. However this is not the case for generic_write_checks with 4 args, where zero means no error. Reviewed-by: Brian Behlendorf Reviewed-by: Haakan T Johansson Signed-off-by: Chunwei Chen Closes #5720 Closes #5726 --- module/zfs/zpl_file.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/module/zfs/zpl_file.c b/module/zfs/zpl_file.c index 75a3b55d1..b625d8412 100644 --- a/module/zfs/zpl_file.c +++ b/module/zfs/zpl_file.c @@ -387,6 +387,8 @@ zpl_iter_write(struct kiocb *kiocb, struct iov_iter *from) count = iov_iter_count(from); ret = generic_write_checks(file, &kiocb->ki_pos, &count, isblk); + if (ret) + return (ret); #else /* * XXX - ideally this check should be in the same lock region with @@ -394,10 +396,10 @@ zpl_iter_write(struct kiocb *kiocb, struct iov_iter *from) * append and someone else grow the file. */ ret = generic_write_checks(kiocb, from); - count = ret; -#endif if (ret <= 0) return (ret); + count = ret; +#endif if (from->type & ITER_KVEC) seg = UIO_SYSSPACE;