Commit b2348fe6 authored by Kent Overstreet's avatar Kent Overstreet
Browse files

bcachefs: Fix *__bch2_trans_subbuf_alloc() error path 



Don't change buf->size on error - this would usually be a transaction
restart, but it could also be -ENOMEM - when we've exceeded the bump
allocator max).

Fixes: 247abee6 ("bcachefs: btree_trans_subbuf")
Signed-off-by: default avatarKent Overstreet <kent.overstreet@linux.dev>
parent 43463598

fs/bcachefs/btree_update.c

+11 −5
Original line number Diff line number Diff line
@@ -549,20 +549,26 @@ void *__bch2_trans_subbuf_alloc(struct btree_trans *trans, 
				unsigned u64s)

{

	unsigned new_top = buf->u64s + u64s;

	unsigned old_size = buf->size;

	unsigned new_size = buf->size;



	if (new_top > buf->size)

		buf->size = roundup_pow_of_two(new_top);

	BUG_ON(roundup_pow_of_two(new_top) > U16_MAX);



	void *n = bch2_trans_kmalloc_nomemzero(trans, buf->size * sizeof(u64));

	if (new_top > new_size)

		new_size = roundup_pow_of_two(new_top);



	void *n = bch2_trans_kmalloc_nomemzero(trans, new_size * sizeof(u64));

	if (IS_ERR(n))

		return n;



	unsigned offset = (u64 *) n - (u64 *) trans->mem;

	BUG_ON(offset > U16_MAX);



	if (buf->u64s)

		memcpy(n,

		       btree_trans_subbuf_base(trans, buf),

		       old_size * sizeof(u64));

		       buf->size * sizeof(u64));

	buf->base = (u64 *) n - (u64 *) trans->mem;

	buf->size = new_size;



	void *p = btree_trans_subbuf_top(trans, buf);

	buf->u64s = new_top;