From 62898dd12ba017c56c39a74ef891845118b0c190 Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Mon, 14 Aug 2023 22:29:41 -0400 Subject: bcachefs: Fix swallowing of data in buffered write path In __bch2_buffered_write, if we fail to write to an entire !uptodate folio, we have to back out the write, bail out and retry. But we were missing an iov_iter_revert() call, so the data written to the folio was lost and the rest of the write shifted to the wrong offset. Signed-off-by: Kent Overstreet --- fs/bcachefs/fs-io-buffered.c | 1 + 1 file changed, 1 insertion(+) (limited to 'fs/bcachefs/fs-io-buffered.c') diff --git a/fs/bcachefs/fs-io-buffered.c b/fs/bcachefs/fs-io-buffered.c index 102c70887f76..dc22182d532f 100644 --- a/fs/bcachefs/fs-io-buffered.c +++ b/fs/bcachefs/fs-io-buffered.c @@ -909,6 +909,7 @@ static int __bch2_buffered_write(struct bch_inode_info *inode, if (!folio_test_uptodate(f) && f_copied != folio_size(f) && pos + copied + f_copied < inode->v.i_size) { + iov_iter_revert(iter, f_copied); folio_zero_range(f, 0, folio_size(f)); folios_trunc(&folios, fi); break; -- cgit v1.2.3