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linux/fs/bcachefs/sb-downgrade.c
Jeongjun Park a25a83de45 bcachefs: fix null-ptr-deref in have_stripes()
c->btree_roots_known[i].b can be NULL. In this case, a NULL pointer dereference
occurs, so you need to add code to check the variable.

Reported-by: syzbot+b468b9fef56949c3b528@syzkaller.appspotmail.com
Fixes: 7773df19c3 ("bcachefs: metadata version bucket_stripe_sectors")
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-10-25 13:17:06 -04:00

417 lines
13 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Superblock section that contains a list of recovery passes to run when
* downgrading past a given version
*/
#include "bcachefs.h"
#include "darray.h"
#include "recovery_passes.h"
#include "sb-downgrade.h"
#include "sb-errors.h"
#include "super-io.h"
#define RECOVERY_PASS_ALL_FSCK BIT_ULL(63)
/*
* Upgrade, downgrade tables - run certain recovery passes, fix certain errors
*
* x(version, recovery_passes, errors...)
*/
#define UPGRADE_TABLE() \
x(backpointers, \
RECOVERY_PASS_ALL_FSCK) \
x(inode_v3, \
RECOVERY_PASS_ALL_FSCK) \
x(unwritten_extents, \
RECOVERY_PASS_ALL_FSCK) \
x(bucket_gens, \
BIT_ULL(BCH_RECOVERY_PASS_bucket_gens_init)| \
RECOVERY_PASS_ALL_FSCK) \
x(lru_v2, \
RECOVERY_PASS_ALL_FSCK) \
x(fragmentation_lru, \
RECOVERY_PASS_ALL_FSCK) \
x(no_bps_in_alloc_keys, \
RECOVERY_PASS_ALL_FSCK) \
x(snapshot_trees, \
RECOVERY_PASS_ALL_FSCK) \
x(snapshot_skiplists, \
BIT_ULL(BCH_RECOVERY_PASS_check_snapshots), \
BCH_FSCK_ERR_snapshot_bad_depth, \
BCH_FSCK_ERR_snapshot_bad_skiplist) \
x(deleted_inodes, \
BIT_ULL(BCH_RECOVERY_PASS_check_inodes), \
BCH_FSCK_ERR_unlinked_inode_not_on_deleted_list) \
x(rebalance_work, \
BIT_ULL(BCH_RECOVERY_PASS_set_fs_needs_rebalance)) \
x(subvolume_fs_parent, \
BIT_ULL(BCH_RECOVERY_PASS_check_dirents), \
BCH_FSCK_ERR_subvol_fs_path_parent_wrong) \
x(btree_subvolume_children, \
BIT_ULL(BCH_RECOVERY_PASS_check_subvols), \
BCH_FSCK_ERR_subvol_children_not_set) \
x(mi_btree_bitmap, \
BIT_ULL(BCH_RECOVERY_PASS_check_allocations), \
BCH_FSCK_ERR_btree_bitmap_not_marked) \
x(disk_accounting_v2, \
BIT_ULL(BCH_RECOVERY_PASS_check_allocations), \
BCH_FSCK_ERR_bkey_version_in_future, \
BCH_FSCK_ERR_dev_usage_buckets_wrong, \
BCH_FSCK_ERR_dev_usage_sectors_wrong, \
BCH_FSCK_ERR_dev_usage_fragmented_wrong, \
BCH_FSCK_ERR_accounting_mismatch) \
x(disk_accounting_v3, \
BIT_ULL(BCH_RECOVERY_PASS_check_allocations), \
BCH_FSCK_ERR_bkey_version_in_future, \
BCH_FSCK_ERR_dev_usage_buckets_wrong, \
BCH_FSCK_ERR_dev_usage_sectors_wrong, \
BCH_FSCK_ERR_dev_usage_fragmented_wrong, \
BCH_FSCK_ERR_accounting_mismatch, \
BCH_FSCK_ERR_accounting_key_replicas_nr_devs_0, \
BCH_FSCK_ERR_accounting_key_replicas_nr_required_bad, \
BCH_FSCK_ERR_accounting_key_replicas_devs_unsorted, \
BCH_FSCK_ERR_accounting_key_junk_at_end) \
x(disk_accounting_inum, \
BIT_ULL(BCH_RECOVERY_PASS_check_allocations), \
BCH_FSCK_ERR_accounting_mismatch) \
x(rebalance_work_acct_fix, \
BIT_ULL(BCH_RECOVERY_PASS_check_allocations), \
BCH_FSCK_ERR_accounting_mismatch) \
x(inode_has_child_snapshots, \
BIT_ULL(BCH_RECOVERY_PASS_check_inodes), \
BCH_FSCK_ERR_inode_has_child_snapshots_wrong)
#define DOWNGRADE_TABLE() \
x(bucket_stripe_sectors, \
0) \
x(disk_accounting_v2, \
BIT_ULL(BCH_RECOVERY_PASS_check_allocations), \
BCH_FSCK_ERR_dev_usage_buckets_wrong, \
BCH_FSCK_ERR_dev_usage_sectors_wrong, \
BCH_FSCK_ERR_dev_usage_fragmented_wrong, \
BCH_FSCK_ERR_fs_usage_hidden_wrong, \
BCH_FSCK_ERR_fs_usage_btree_wrong, \
BCH_FSCK_ERR_fs_usage_data_wrong, \
BCH_FSCK_ERR_fs_usage_cached_wrong, \
BCH_FSCK_ERR_fs_usage_reserved_wrong, \
BCH_FSCK_ERR_fs_usage_nr_inodes_wrong, \
BCH_FSCK_ERR_fs_usage_persistent_reserved_wrong, \
BCH_FSCK_ERR_fs_usage_replicas_wrong, \
BCH_FSCK_ERR_bkey_version_in_future) \
x(disk_accounting_v3, \
BIT_ULL(BCH_RECOVERY_PASS_check_allocations), \
BCH_FSCK_ERR_dev_usage_buckets_wrong, \
BCH_FSCK_ERR_dev_usage_sectors_wrong, \
BCH_FSCK_ERR_dev_usage_fragmented_wrong, \
BCH_FSCK_ERR_fs_usage_hidden_wrong, \
BCH_FSCK_ERR_fs_usage_btree_wrong, \
BCH_FSCK_ERR_fs_usage_data_wrong, \
BCH_FSCK_ERR_fs_usage_cached_wrong, \
BCH_FSCK_ERR_fs_usage_reserved_wrong, \
BCH_FSCK_ERR_fs_usage_nr_inodes_wrong, \
BCH_FSCK_ERR_fs_usage_persistent_reserved_wrong, \
BCH_FSCK_ERR_fs_usage_replicas_wrong, \
BCH_FSCK_ERR_accounting_replicas_not_marked, \
BCH_FSCK_ERR_bkey_version_in_future) \
x(rebalance_work_acct_fix, \
BIT_ULL(BCH_RECOVERY_PASS_check_allocations), \
BCH_FSCK_ERR_accounting_mismatch)
struct upgrade_downgrade_entry {
u64 recovery_passes;
u16 version;
u16 nr_errors;
const u16 *errors;
};
#define x(ver, passes, ...) static const u16 upgrade_##ver##_errors[] = { __VA_ARGS__ };
UPGRADE_TABLE()
#undef x
static const struct upgrade_downgrade_entry upgrade_table[] = {
#define x(ver, passes, ...) { \
.recovery_passes = passes, \
.version = bcachefs_metadata_version_##ver,\
.nr_errors = ARRAY_SIZE(upgrade_##ver##_errors), \
.errors = upgrade_##ver##_errors, \
},
UPGRADE_TABLE()
#undef x
};
static int have_stripes(struct bch_fs *c)
{
if (IS_ERR_OR_NULL(c->btree_roots_known[BTREE_ID_stripes].b))
return 0;
return !btree_node_fake(c->btree_roots_known[BTREE_ID_stripes].b);
}
int bch2_sb_set_upgrade_extra(struct bch_fs *c)
{
unsigned old_version = c->sb.version_upgrade_complete ?: c->sb.version;
unsigned new_version = c->sb.version;
bool write_sb = false;
int ret = 0;
mutex_lock(&c->sb_lock);
struct bch_sb_field_ext *ext = bch2_sb_field_get(c->disk_sb.sb, ext);
if (old_version < bcachefs_metadata_version_bucket_stripe_sectors &&
new_version >= bcachefs_metadata_version_bucket_stripe_sectors &&
(ret = have_stripes(c) > 0)) {
__set_bit_le64(BCH_RECOVERY_PASS_STABLE_check_allocations, ext->recovery_passes_required);
__set_bit_le64(BCH_FSCK_ERR_alloc_key_dirty_sectors_wrong, ext->errors_silent);
__set_bit_le64(BCH_FSCK_ERR_alloc_key_stripe_sectors_wrong, ext->errors_silent);
write_sb = true;
}
if (write_sb)
bch2_write_super(c);
mutex_unlock(&c->sb_lock);
return ret < 0 ? ret : 0;
}
void bch2_sb_set_upgrade(struct bch_fs *c,
unsigned old_version,
unsigned new_version)
{
lockdep_assert_held(&c->sb_lock);
struct bch_sb_field_ext *ext = bch2_sb_field_get(c->disk_sb.sb, ext);
for (const struct upgrade_downgrade_entry *i = upgrade_table;
i < upgrade_table + ARRAY_SIZE(upgrade_table);
i++)
if (i->version > old_version && i->version <= new_version) {
u64 passes = i->recovery_passes;
if (passes & RECOVERY_PASS_ALL_FSCK)
passes |= bch2_fsck_recovery_passes();
passes &= ~RECOVERY_PASS_ALL_FSCK;
ext->recovery_passes_required[0] |=
cpu_to_le64(bch2_recovery_passes_to_stable(passes));
for (const u16 *e = i->errors; e < i->errors + i->nr_errors; e++)
__set_bit_le64(*e, ext->errors_silent);
}
}
#define x(ver, passes, ...) static const u16 downgrade_##ver##_errors[] = { __VA_ARGS__ };
DOWNGRADE_TABLE()
#undef x
static const struct upgrade_downgrade_entry downgrade_table[] = {
#define x(ver, passes, ...) { \
.recovery_passes = passes, \
.version = bcachefs_metadata_version_##ver,\
.nr_errors = ARRAY_SIZE(downgrade_##ver##_errors), \
.errors = downgrade_##ver##_errors, \
},
DOWNGRADE_TABLE()
#undef x
};
static int downgrade_table_extra(struct bch_fs *c, darray_char *table)
{
struct bch_sb_field_downgrade_entry *dst = (void *) &darray_top(*table);
unsigned bytes = sizeof(*dst) + sizeof(dst->errors[0]) * le16_to_cpu(dst->nr_errors);
int ret = 0;
unsigned nr_errors = le16_to_cpu(dst->nr_errors);
switch (le16_to_cpu(dst->version)) {
case bcachefs_metadata_version_bucket_stripe_sectors:
if (have_stripes(c)) {
bytes += sizeof(dst->errors[0]) * 2;
ret = darray_make_room(table, bytes);
if (ret)
return ret;
/* open coded __set_bit_le64, as dst is packed and
* dst->recovery_passes is misaligned */
unsigned b = BCH_RECOVERY_PASS_STABLE_check_allocations;
dst->recovery_passes[b / 64] |= cpu_to_le64(BIT_ULL(b % 64));
dst->errors[nr_errors++] = cpu_to_le16(BCH_FSCK_ERR_alloc_key_dirty_sectors_wrong);
}
break;
}
dst->nr_errors = cpu_to_le16(nr_errors);
return ret;
}
static inline const struct bch_sb_field_downgrade_entry *
downgrade_entry_next_c(const struct bch_sb_field_downgrade_entry *e)
{
return (void *) &e->errors[le16_to_cpu(e->nr_errors)];
}
#define for_each_downgrade_entry(_d, _i) \
for (const struct bch_sb_field_downgrade_entry *_i = (_d)->entries; \
(void *) _i < vstruct_end(&(_d)->field) && \
(void *) &_i->errors[0] <= vstruct_end(&(_d)->field) && \
(void *) downgrade_entry_next_c(_i) <= vstruct_end(&(_d)->field); \
_i = downgrade_entry_next_c(_i))
static int bch2_sb_downgrade_validate(struct bch_sb *sb, struct bch_sb_field *f,
enum bch_validate_flags flags, struct printbuf *err)
{
struct bch_sb_field_downgrade *e = field_to_type(f, downgrade);
for (const struct bch_sb_field_downgrade_entry *i = e->entries;
(void *) i < vstruct_end(&e->field);
i = downgrade_entry_next_c(i)) {
/*
* Careful: sb_field_downgrade_entry is only 2 byte aligned, but
* section sizes are 8 byte aligned - an empty entry spanning
* the end of the section is allowed (and ignored):
*/
if ((void *) &i->errors[0] > vstruct_end(&e->field))
break;
if (flags & BCH_VALIDATE_write &&
(void *) downgrade_entry_next_c(i) > vstruct_end(&e->field)) {
prt_printf(err, "downgrade entry overruns end of superblock section");
return -BCH_ERR_invalid_sb_downgrade;
}
if (BCH_VERSION_MAJOR(le16_to_cpu(i->version)) !=
BCH_VERSION_MAJOR(le16_to_cpu(sb->version))) {
prt_printf(err, "downgrade entry with mismatched major version (%u != %u)",
BCH_VERSION_MAJOR(le16_to_cpu(i->version)),
BCH_VERSION_MAJOR(le16_to_cpu(sb->version)));
return -BCH_ERR_invalid_sb_downgrade;
}
}
return 0;
}
static void bch2_sb_downgrade_to_text(struct printbuf *out, struct bch_sb *sb,
struct bch_sb_field *f)
{
struct bch_sb_field_downgrade *e = field_to_type(f, downgrade);
if (out->nr_tabstops <= 1)
printbuf_tabstop_push(out, 16);
for_each_downgrade_entry(e, i) {
prt_str(out, "version:\t");
bch2_version_to_text(out, le16_to_cpu(i->version));
prt_newline(out);
prt_str(out, "recovery passes:\t");
prt_bitflags(out, bch2_recovery_passes,
bch2_recovery_passes_from_stable(le64_to_cpu(i->recovery_passes[0])));
prt_newline(out);
prt_str(out, "errors:\t");
bool first = true;
for (unsigned j = 0; j < le16_to_cpu(i->nr_errors); j++) {
if (!first)
prt_char(out, ',');
first = false;
bch2_sb_error_id_to_text(out, le16_to_cpu(i->errors[j]));
}
prt_newline(out);
}
}
const struct bch_sb_field_ops bch_sb_field_ops_downgrade = {
.validate = bch2_sb_downgrade_validate,
.to_text = bch2_sb_downgrade_to_text,
};
int bch2_sb_downgrade_update(struct bch_fs *c)
{
if (!test_bit(BCH_FS_btree_running, &c->flags))
return 0;
darray_char table = {};
int ret = 0;
for (const struct upgrade_downgrade_entry *src = downgrade_table;
src < downgrade_table + ARRAY_SIZE(downgrade_table);
src++) {
if (BCH_VERSION_MAJOR(src->version) != BCH_VERSION_MAJOR(le16_to_cpu(c->disk_sb.sb->version)))
continue;
struct bch_sb_field_downgrade_entry *dst;
unsigned bytes = sizeof(*dst) + sizeof(dst->errors[0]) * src->nr_errors;
ret = darray_make_room(&table, bytes);
if (ret)
goto out;
dst = (void *) &darray_top(table);
dst->version = cpu_to_le16(src->version);
dst->recovery_passes[0] = cpu_to_le64(bch2_recovery_passes_to_stable(src->recovery_passes));
dst->recovery_passes[1] = 0;
dst->nr_errors = cpu_to_le16(src->nr_errors);
for (unsigned i = 0; i < src->nr_errors; i++)
dst->errors[i] = cpu_to_le16(src->errors[i]);
ret = downgrade_table_extra(c, &table);
if (ret)
goto out;
if (!dst->recovery_passes[0] &&
!dst->recovery_passes[1] &&
!dst->nr_errors)
continue;
table.nr += sizeof(*dst) + sizeof(dst->errors[0]) * le16_to_cpu(dst->nr_errors);
}
struct bch_sb_field_downgrade *d = bch2_sb_field_get(c->disk_sb.sb, downgrade);
unsigned sb_u64s = DIV_ROUND_UP(sizeof(*d) + table.nr, sizeof(u64));
if (d && le32_to_cpu(d->field.u64s) > sb_u64s)
goto out;
d = bch2_sb_field_resize(&c->disk_sb, downgrade, sb_u64s);
if (!d) {
ret = -BCH_ERR_ENOSPC_sb_downgrade;
goto out;
}
memcpy(d->entries, table.data, table.nr);
memset_u64s_tail(d->entries, 0, table.nr);
out:
darray_exit(&table);
return ret;
}
void bch2_sb_set_downgrade(struct bch_fs *c, unsigned new_minor, unsigned old_minor)
{
struct bch_sb_field_downgrade *d = bch2_sb_field_get(c->disk_sb.sb, downgrade);
if (!d)
return;
struct bch_sb_field_ext *ext = bch2_sb_field_get(c->disk_sb.sb, ext);
for_each_downgrade_entry(d, i) {
unsigned minor = BCH_VERSION_MINOR(le16_to_cpu(i->version));
if (new_minor < minor && minor <= old_minor) {
ext->recovery_passes_required[0] |= i->recovery_passes[0];
ext->recovery_passes_required[1] |= i->recovery_passes[1];
for (unsigned j = 0; j < le16_to_cpu(i->nr_errors); j++) {
unsigned e = le16_to_cpu(i->errors[j]);
if (e < BCH_FSCK_ERR_MAX)
__set_bit(e, c->sb.errors_silent);
if (e < sizeof(ext->errors_silent) * 8)
__set_bit_le64(e, ext->errors_silent);
}
}
}
}