On Fri 23-06-17 21:37:21, Ernesto A. Fernández wrote: > Buffer heads referencing indirect blocks may not be released if the file > is truncated at the right time. This happens because ext2_get_branch() > returns NULL when it finds the whole chain of indirect blocks already > set, and when truncate alters the chain this value of NULL is > treated as the address of the last head to be released. Handle this in the > same way as it's done after the got_it label. > > Signed-off-by: Ernesto A. Fernández <ernesto.mnd.fernandez@xxxxxxxxx> > --- > Despite trying I haven't actually managed to trigger this race. I tested > the patch by inducing regular failures in verify_chain(). Thanks! I've merged the patch to my tree. Honza > > fs/ext2/inode.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c > index 2dcbd56..30163d0 100644 > --- a/fs/ext2/inode.c > +++ b/fs/ext2/inode.c > @@ -659,6 +659,7 @@ static int ext2_get_blocks(struct inode *inode, > */ > err = -EAGAIN; > count = 0; > + partial = chain + depth - 1; > break; > } > blk = le32_to_cpu(*(chain[depth-1].p + count)); > -- > 2.1.4 > > -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR
