From f765b134c0d3f294f6084d3e0a11de184059a387 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Mon, 6 Apr 2015 20:50:38 -0400 Subject: new_sync_write(): discard ->ki_pos unless the return value is positive That allows ->write_iter() instances much more convenient life wrt iocb->ki_pos (and fixes several filesystems with borderline POSIX violations when zero-length write succeeds and changes the current position). Signed-off-by: Al Viro --- fs/read_write.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/read_write.c b/fs/read_write.c index 45d583c33879..819ef3faf1bb 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -477,7 +477,8 @@ static ssize_t new_sync_write(struct file *filp, const char __user *buf, size_t ret = filp->f_op->write_iter(&kiocb, &iter); BUG_ON(ret == -EIOCBQUEUED); - *ppos = kiocb.ki_pos; + if (ret > 0) + *ppos = kiocb.ki_pos; return ret; } -- cgit v1.2.3