Commit 6b8cbfc3 authored by Kent Overstreet's avatar Kent Overstreet
Browse files

bcachefs: Fix assert in bch2_alloc_v4_invalid() 



Reported-by: default avatar <syzbot+10827fa6b176e1acf1d0@syzkaller.appspotmail.com>
Signed-off-by: default avatarKent Overstreet <kent.overstreet@linux.dev>
parent 9a0ec045

fs/bcachefs/alloc_background.c

+2 −2
Original line number Diff line number Diff line
@@ -244,10 +244,10 @@ int bch2_alloc_v4_invalid(struct bch_fs *c, struct bkey_s_c k, 
	struct bkey_s_c_alloc_v4 a = bkey_s_c_to_alloc_v4(k);

	int ret = 0;



	bkey_fsck_err_on(alloc_v4_u64s(a.v) > bkey_val_u64s(k.k), c, err,

	bkey_fsck_err_on(alloc_v4_u64s_noerror(a.v) > bkey_val_u64s(k.k), c, err,

			 alloc_v4_val_size_bad,

			 "bad val size (%u > %zu)",

			 alloc_v4_u64s(a.v), bkey_val_u64s(k.k));

			 alloc_v4_u64s_noerror(a.v), bkey_val_u64s(k.k));



	bkey_fsck_err_on(!BCH_ALLOC_V4_BACKPOINTERS_START(a.v) &&

			 BCH_ALLOC_V4_NR_BACKPOINTERS(a.v), c, err,

fs/bcachefs/alloc_background.h

+6 −2
Original line number Diff line number Diff line
@@ -126,13 +126,17 @@ static inline struct bpos alloc_freespace_pos(struct bpos pos, struct bch_alloc_ 
	return pos;

}



static inline unsigned alloc_v4_u64s(const struct bch_alloc_v4 *a)

static inline unsigned alloc_v4_u64s_noerror(const struct bch_alloc_v4 *a)

{

	unsigned ret = (BCH_ALLOC_V4_BACKPOINTERS_START(a) ?:

	return (BCH_ALLOC_V4_BACKPOINTERS_START(a) ?:

			BCH_ALLOC_V4_U64s_V0) +

		BCH_ALLOC_V4_NR_BACKPOINTERS(a) *

		(sizeof(struct bch_backpointer) / sizeof(u64));

}



static inline unsigned alloc_v4_u64s(const struct bch_alloc_v4 *a)

{

	unsigned ret = alloc_v4_u64s_noerror(a);

	BUG_ON(ret > U8_MAX - BKEY_U64s);

	return ret;

}