From bd2843fe1f29f6145c623ae9390f144cefaa611d Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 9 Sep 2015 10:16:39 +0100 Subject: fix ufs write vs readpage race when writing into a hole Followup to the UFS series - with the way we clear the new blocks (via buffer cache, possibly on more than a page worth of file) we really should not insert a reference to new block into inode block tree until after we'd cleared it. Signed-off-by: Al Viro Signed-off-by: Linus Torvalds --- fs/ufs/balloc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs') diff --git a/fs/ufs/balloc.c b/fs/ufs/balloc.c index fb8b54eb77c5..dc5fae601c24 100644 --- a/fs/ufs/balloc.c +++ b/fs/ufs/balloc.c @@ -417,14 +417,14 @@ u64 ufs_new_fragments(struct inode *inode, void *p, u64 fragment, if (oldcount == 0) { result = ufs_alloc_fragments (inode, cgno, goal, count, err); if (result) { + ufs_clear_frags(inode, result + oldcount, + newcount - oldcount, locked_page != NULL); write_seqlock(&UFS_I(inode)->meta_lock); ufs_cpu_to_data_ptr(sb, p, result); write_sequnlock(&UFS_I(inode)->meta_lock); *err = 0; UFS_I(inode)->i_lastfrag = max(UFS_I(inode)->i_lastfrag, fragment + count); - ufs_clear_frags(inode, result + oldcount, - newcount - oldcount, locked_page != NULL); } mutex_unlock(&UFS_SB(sb)->s_lock); UFSD("EXIT, result %llu\n", (unsigned long long)result); -- cgit v1.2.3