* [PATCH v1.2 1/3] btrfs: tree-checker: Add EXTENT_ITEM and METADATA_ITEM check
2019-08-09 1:24 [PATCH v1.2 0/3] btrfs: tree-checker: Add extent items check Qu Wenruo
@ 2019-08-09 1:24 ` Qu Wenruo
2019-08-22 14:59 ` David Sterba
2019-08-09 1:24 ` [PATCH v1.2 2/3] btrfs: tree-checker: Add simple keyed refs check Qu Wenruo
` (2 subsequent siblings)
3 siblings, 1 reply; 9+ messages in thread
From: Qu Wenruo @ 2019-08-09 1:24 UTC (permalink / raw)
To: linux-btrfs
This patch introduces the ability to check extent items.
This check involves:
- key->objectid check
Basic alignment check.
- key->type check
Against btrfs_extent_item::type and SKINNY_METADATA feature.
- key->offset alignment check for EXTENT_ITEM
- key->offset check for METADATA_ITEM
- item size check
Both against minimal size and stepping check.
- btrfs_extent_item check
Checks its flags and generation.
- btrfs_extent_inline_ref checks
Against 4 types inline ref.
Checks bytenr alignment and tree level.
- btrfs_extent_item::refs check
Check against total refs found in inline refs.
This check would be the most complex single item check due to its nature
of inlined items.
Signed-off-by: Qu Wenruo <wqu@suse.com>
---
fs/btrfs/tree-checker.c | 250 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 250 insertions(+)
diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c
index 71bbbce3076d..836f5d8a8ebe 100644
--- a/fs/btrfs/tree-checker.c
+++ b/fs/btrfs/tree-checker.c
@@ -899,6 +899,252 @@ static int check_root_item(struct extent_buffer *leaf, struct btrfs_key *key,
return 0;
}
+__printf(3,4)
+__cold
+static void extent_err(const struct extent_buffer *eb, int slot,
+ const char *fmt, ...)
+{
+ struct btrfs_key key;
+ struct va_format vaf;
+ va_list args;
+ u64 bytenr;
+ u64 len;
+
+ btrfs_item_key_to_cpu(eb, &key, slot);
+ bytenr = key.objectid;
+ if (key.type == BTRFS_METADATA_ITEM_KEY)
+ len = eb->fs_info->nodesize;
+ else
+ len = key.offset;
+ va_start(args, fmt);
+
+ vaf.fmt = fmt;
+ vaf.va = &args;
+
+ btrfs_crit(eb->fs_info,
+ "corrupt %s: block=%llu slot=%d extent bytenr=%llu len=%llu %pV",
+ btrfs_header_level(eb) == 0 ? "leaf" : "node",
+ eb->start, slot, bytenr, len, &vaf);
+ va_end(args);
+}
+
+static int check_extent_item(struct extent_buffer *leaf,
+ struct btrfs_key *key, int slot)
+{
+ struct btrfs_fs_info *fs_info = leaf->fs_info;
+ struct btrfs_extent_item *ei;
+ bool is_tree_block = false;
+ unsigned long ptr; /* Current pointer inside inline refs */
+ unsigned long end; /* Extent item end */
+ u32 item_size = btrfs_item_size_nr(leaf, slot);
+ u64 flags;
+ u64 generation;
+ u64 total_refs; /* Total refs in btrfs_extent_item */
+ u64 inline_refs = 0; /* found total inline refs */
+
+ if (key->type == BTRFS_METADATA_ITEM_KEY &&
+ !btrfs_fs_incompat(fs_info, SKINNY_METADATA)) {
+ generic_err(leaf, slot,
+"invalid key type, METADATA_ITEM type invalid when SKINNY_METADATA feature disabled");
+ return -EUCLEAN;
+ }
+ /* key->objectid is the bytenr for both key types */
+ if (!IS_ALIGNED(key->objectid, fs_info->sectorsize)) {
+ generic_err(leaf, slot,
+"invalid key objectid, have %llu expect to be aligned to %u",
+ key->objectid, fs_info->sectorsize);
+ return -EUCLEAN;
+ }
+
+ /* key->offset is tree level for METADATA_ITEM_KEY */
+ if (key->type == BTRFS_METADATA_ITEM_KEY &&
+ key->offset >= BTRFS_MAX_LEVEL) {
+ extent_err(leaf, slot,
+ "invalid tree level, have %llu expect [0, %u]",
+ key->offset, BTRFS_MAX_LEVEL - 1);
+ return -EUCLEAN;
+ }
+
+ /*
+ * EXTENT/METADATA_ITEM is consistent of:
+ * 1) One btrfs_extent_item
+ * Records the total refs, type and generation of the extent.
+ *
+ * 2) One btrfs_tree_block_info (for EXTENT_ITEM and tree backref only)
+ * Records the first key and level of the tree block.
+ *
+ * 2) *Zero* or more btrfs_extent_inline_ref(s)
+ * Each inline ref has one btrfs_extent_inline_ref shows:
+ * 2.1) The ref type, one of the 4
+ * TREE_BLOCK_REF Tree block only
+ * SHARED_BLOCK_REF Tree block only
+ * EXTENT_DATA_REF Data only
+ * SHARED_DATA_REF Data only
+ * 2.2) Ref type specific data
+ * Either using btrfs_extent_inline_ref::offset, or specific
+ * data structure.
+ */
+ if (item_size < sizeof(*ei)) {
+ extent_err(leaf, slot,
+ "invalid item size, have %u expect [%zu, %u)",
+ item_size, sizeof(*ei),
+ BTRFS_LEAF_DATA_SIZE(fs_info));
+ return -EUCLEAN;
+ }
+ end = item_size + btrfs_item_ptr_offset(leaf, slot);
+
+ /* Checks against extent_item */
+ ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item);
+ flags = btrfs_extent_flags(leaf, ei);
+ total_refs = btrfs_extent_refs(leaf, ei);
+ generation = btrfs_extent_generation(leaf, ei);
+ if (generation > btrfs_super_generation(fs_info->super_copy) + 1) {
+ extent_err(leaf, slot,
+ "invalid generation, have %llu expect (0, %llu]",
+ generation,
+ btrfs_super_generation(fs_info->super_copy) + 1);
+ return -EUCLEAN;
+ }
+ if (!is_power_of_2(flags & (BTRFS_EXTENT_FLAG_DATA |
+ BTRFS_EXTENT_FLAG_TREE_BLOCK))) {
+ extent_err(leaf, slot,
+ "invalid extent flag, have 0x%llx expect 1 bit set in 0x%llx",
+ flags, BTRFS_EXTENT_FLAG_DATA |
+ BTRFS_EXTENT_FLAG_TREE_BLOCK);
+ return -EUCLEAN;
+ }
+ is_tree_block = !!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK);
+ if (is_tree_block) {
+ if (key->type == BTRFS_EXTENT_ITEM_KEY &&
+ key->offset != fs_info->nodesize) {
+ extent_err(leaf, slot,
+ "invalid extent length, have %llu expect %u",
+ key->offset, fs_info->nodesize);
+ return -EUCLEAN;
+ }
+ } else {
+ if (key->type != BTRFS_EXTENT_ITEM_KEY) {
+ extent_err(leaf, slot,
+ "invalid key type, have %u expect %u for data backref",
+ key->type, BTRFS_EXTENT_ITEM_KEY);
+ return -EUCLEAN;
+ }
+ if (!IS_ALIGNED(key->offset, fs_info->sectorsize)) {
+ extent_err(leaf, slot,
+ "invalid extent length, have %llu expect aligned to %u",
+ key->offset, fs_info->sectorsize);
+ return -EUCLEAN;
+ }
+ }
+ ptr = (unsigned long)(struct btrfs_extent_item *)(ei + 1);
+
+ /* Check the special case of btrfs_tree_block_info */
+ if (is_tree_block && key->type != BTRFS_METADATA_ITEM_KEY) {
+ struct btrfs_tree_block_info *info;
+
+ info = (struct btrfs_tree_block_info *)ptr;
+ if (btrfs_tree_block_level(leaf, info) >= BTRFS_MAX_LEVEL) {
+ extent_err(leaf, slot,
+ "invalid tree block info level, have %u expect [0, %u]",
+ btrfs_tree_block_level(leaf, info),
+ BTRFS_MAX_LEVEL - 1);
+ return -EUCLEAN;
+ }
+ ptr = (unsigned long)(struct btrfs_tree_block_info *)(info + 1);
+ }
+
+ /* Check inline refs */
+ while (ptr < end) {
+ struct btrfs_extent_inline_ref *iref;
+ struct btrfs_extent_data_ref *dref;
+ struct btrfs_shared_data_ref *sref;
+ u64 dref_offset;
+ u64 inline_offset;
+ u8 inline_type;
+
+ if (ptr + sizeof(*iref) > end) {
+ extent_err(leaf, slot,
+"inline ref item overflows extent item, ptr %lu iref size %zu end %lu",
+ ptr, sizeof(*iref), end);
+ goto err;
+ }
+ iref = (struct btrfs_extent_inline_ref *)ptr;
+ inline_type = btrfs_extent_inline_ref_type(leaf, iref);
+ inline_offset = btrfs_extent_inline_ref_offset(leaf, iref);
+ if (ptr + btrfs_extent_inline_ref_size(inline_type) > end) {
+ extent_err(leaf, slot,
+"inline ref item overflows extent item, ptr %lu iref size %u end %lu",
+ ptr, inline_type, end);
+ goto err;
+ }
+
+ switch (inline_type) {
+ /* inline_offset is subvolid of the owner, no need to check */
+ case BTRFS_TREE_BLOCK_REF_KEY:
+ inline_refs++;
+ break;
+ /* contains parent bytenr */
+ case BTRFS_SHARED_BLOCK_REF_KEY:
+ if (!IS_ALIGNED(inline_offset, fs_info->sectorsize)) {
+ extent_err(leaf, slot,
+ "invalid tree parent bytenr, have %llu expect aligned to %u",
+ inline_offset, fs_info->sectorsize);
+ goto err;
+ }
+ inline_refs++;
+ break;
+ /*
+ * contains owner subvolid, owner key objectid, adjusted offset.
+ * the only obvious corruption can happen in that offset.
+ */
+ case BTRFS_EXTENT_DATA_REF_KEY:
+ dref = (struct btrfs_extent_data_ref *)(&iref->offset);
+ dref_offset = btrfs_extent_data_ref_offset(leaf, dref);
+ if (!IS_ALIGNED(dref_offset, fs_info->sectorsize)) {
+ extent_err(leaf, slot,
+ "invalid data ref offset, have %llu expect aligned to %u",
+ dref_offset, fs_info->sectorsize);
+ goto err;
+ }
+ inline_refs += btrfs_extent_data_ref_count(leaf, dref);
+ break;
+ /* contains parent bytenr and ref count */
+ case BTRFS_SHARED_DATA_REF_KEY:
+ sref = (struct btrfs_shared_data_ref *)(iref + 1);
+ if (!IS_ALIGNED(inline_offset, fs_info->sectorsize)) {
+ extent_err(leaf, slot,
+ "invalid data parent bytenr, have %llu expect aligned to %u",
+ inline_offset, fs_info->sectorsize);
+ goto err;
+ }
+ inline_refs += btrfs_shared_data_ref_count(leaf, sref);
+ break;
+ default:
+ extent_err(leaf, slot, "unknown inline ref type: %u",
+ inline_type);
+ goto err;
+ }
+ ptr += btrfs_extent_inline_ref_size(inline_type);
+ }
+ /* No padding is allowed */
+ if (ptr != end) {
+ extent_err(leaf, slot,
+ "invalid extent item size, padding bytes found");
+ goto err;
+ }
+
+ /* Finally, check the inline refs against total refs */
+ if (inline_refs > total_refs) {
+ extent_err(leaf, slot,
+ "invalid extent refs, have %llu expect >= inline %llu",
+ total_refs, inline_refs);
+ goto err;
+ }
+ return 0;
+err:
+ return -EUCLEAN;
+}
+
/*
* Common point to switch the item-specific validation.
*/
@@ -937,6 +1183,10 @@ static int check_leaf_item(struct extent_buffer *leaf,
case BTRFS_ROOT_ITEM_KEY:
ret = check_root_item(leaf, key, slot);
break;
+ case BTRFS_EXTENT_ITEM_KEY:
+ case BTRFS_METADATA_ITEM_KEY:
+ ret = check_extent_item(leaf, key, slot);
+ break;
}
return ret;
}
--
2.22.0
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH v1.2 2/3] btrfs: tree-checker: Add simple keyed refs check
2019-08-09 1:24 [PATCH v1.2 0/3] btrfs: tree-checker: Add extent items check Qu Wenruo
2019-08-09 1:24 ` [PATCH v1.2 1/3] btrfs: tree-checker: Add EXTENT_ITEM and METADATA_ITEM check Qu Wenruo
@ 2019-08-09 1:24 ` Qu Wenruo
[not found] ` <CAKzB54SN1FmGhGHQOfT2fvn=ESQn4vOwbPpPM7p8eJRkNmvf7w@mail.gmail.com>
2019-08-22 15:02 ` [PATCH v1.2 2/3] btrfs: tree-checker: Add simple keyed refs check David Sterba
2019-08-09 1:24 ` [PATCH v1.2 3/3] btrfs: tree-checker: Add EXTENT_DATA_REF check Qu Wenruo
2019-08-22 15:08 ` [PATCH v1.2 0/3] btrfs: tree-checker: Add extent items check David Sterba
3 siblings, 2 replies; 9+ messages in thread
From: Qu Wenruo @ 2019-08-09 1:24 UTC (permalink / raw)
To: linux-btrfs
For TREE_BLOCK_REF, SHARED_DATA_REF and SHARED_BLOCK_REF we need to
check:
| TREE_BLOCK_REF | SHARED_BLOCK_REF | SHARED_BLOCK_REF
--------------+----------------+-----------------+------------------
key->objectid | Alignment | Alignment | Alignment
key->offset | Any value | Alignment | Alignment
item_size | 0 | 0 | sizeof(le32) (*)
*: sizeof(struct btrfs_shared_data_ref)
So introduce a check to check all these 3 key types together.
Signed-off-by: Qu Wenruo <wqu@suse.com>
---
fs/btrfs/tree-checker.c | 40 +++++++++++++++++++++++++++++++++++++++-
1 file changed, 39 insertions(+), 1 deletion(-)
diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c
index 836f5d8a8ebe..39d10b553c5f 100644
--- a/fs/btrfs/tree-checker.c
+++ b/fs/btrfs/tree-checker.c
@@ -912,7 +912,9 @@ static void extent_err(const struct extent_buffer *eb, int slot,
btrfs_item_key_to_cpu(eb, &key, slot);
bytenr = key.objectid;
- if (key.type == BTRFS_METADATA_ITEM_KEY)
+ if (key.type == BTRFS_METADATA_ITEM_KEY ||
+ key.type == BTRFS_TREE_BLOCK_REF_KEY ||
+ key.type == BTRFS_SHARED_BLOCK_REF_KEY)
len = eb->fs_info->nodesize;
else
len = key.offset;
@@ -1145,6 +1147,37 @@ static int check_extent_item(struct extent_buffer *leaf,
return -EUCLEAN;
}
+static int check_simple_keyed_refs(struct extent_buffer *leaf,
+ struct btrfs_key *key, int slot)
+{
+ u32 expect_item_size = 0;
+
+ if (key->type == BTRFS_SHARED_DATA_REF_KEY)
+ expect_item_size = sizeof(struct btrfs_shared_data_ref);
+
+ if (btrfs_item_size_nr(leaf, slot) != expect_item_size) {
+ generic_err(leaf, slot,
+ "invalid item size, have %u expect %u for key type %u",
+ btrfs_item_size_nr(leaf, slot),
+ expect_item_size, key->type);
+ return -EUCLEAN;
+ }
+ if (!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize)) {
+ generic_err(leaf, slot,
+"invalid key objectid for shared block ref, have %llu expect aligned to %u",
+ key->objectid, leaf->fs_info->sectorsize);
+ return -EUCLEAN;
+ }
+ if (key->type != BTRFS_TREE_BLOCK_REF_KEY &&
+ !IS_ALIGNED(key->offset, leaf->fs_info->sectorsize)) {
+ extent_err(leaf, slot,
+ "invalid tree parent bytenr, have %llu expect aligned to %u",
+ key->offset, leaf->fs_info->sectorsize);
+ return -EUCLEAN;
+ }
+ return 0;
+}
+
/*
* Common point to switch the item-specific validation.
*/
@@ -1187,6 +1220,11 @@ static int check_leaf_item(struct extent_buffer *leaf,
case BTRFS_METADATA_ITEM_KEY:
ret = check_extent_item(leaf, key, slot);
break;
+ case BTRFS_TREE_BLOCK_REF_KEY:
+ case BTRFS_SHARED_DATA_REF_KEY:
+ case BTRFS_SHARED_BLOCK_REF_KEY:
+ ret = check_simple_keyed_refs(leaf, key, slot);
+ break;
}
return ret;
}
--
2.22.0
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH v1.2 3/3] btrfs: tree-checker: Add EXTENT_DATA_REF check
2019-08-09 1:24 [PATCH v1.2 0/3] btrfs: tree-checker: Add extent items check Qu Wenruo
2019-08-09 1:24 ` [PATCH v1.2 1/3] btrfs: tree-checker: Add EXTENT_ITEM and METADATA_ITEM check Qu Wenruo
2019-08-09 1:24 ` [PATCH v1.2 2/3] btrfs: tree-checker: Add simple keyed refs check Qu Wenruo
@ 2019-08-09 1:24 ` Qu Wenruo
2019-08-22 15:08 ` [PATCH v1.2 0/3] btrfs: tree-checker: Add extent items check David Sterba
3 siblings, 0 replies; 9+ messages in thread
From: Qu Wenruo @ 2019-08-09 1:24 UTC (permalink / raw)
To: linux-btrfs
EXTENT_DATA_REF is a little like DIR_ITEM which contains hash in its
key->offset.
This patch will check the following contents:
- Key->objectid
Basic alignment check.
- Hash
Hash of each extent_data_ref item must match key->offset.
- Offset
Basic alignment check.
Signed-off-by: Qu Wenruo <wqu@suse.com>
---
fs/btrfs/ctree.h | 1 +
fs/btrfs/extent-tree.c | 2 +-
fs/btrfs/tree-checker.c | 48 +++++++++++++++++++++++++++++++++++++++++
3 files changed, 50 insertions(+), 1 deletion(-)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 0a61dff27f57..710ea3a6608c 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -2679,6 +2679,7 @@ enum btrfs_inline_ref_type {
int btrfs_get_extent_inline_ref_type(const struct extent_buffer *eb,
struct btrfs_extent_inline_ref *iref,
enum btrfs_inline_ref_type is_data);
+u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset);
u64 btrfs_csum_bytes_to_leaves(struct btrfs_fs_info *fs_info, u64 csum_bytes);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index b4e9e36b65f1..c0888ed503df 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -1114,7 +1114,7 @@ int btrfs_get_extent_inline_ref_type(const struct extent_buffer *eb,
return BTRFS_REF_TYPE_INVALID;
}
-static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
+u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
{
u32 high_crc = ~(u32)0;
u32 low_crc = ~(u32)0;
diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c
index 39d10b553c5f..2a0624bf7789 100644
--- a/fs/btrfs/tree-checker.c
+++ b/fs/btrfs/tree-checker.c
@@ -1178,6 +1178,51 @@ static int check_simple_keyed_refs(struct extent_buffer *leaf,
return 0;
}
+static int check_extent_data_ref(struct extent_buffer *leaf,
+ struct btrfs_key *key, int slot)
+{
+ struct btrfs_extent_data_ref *dref;
+ unsigned long ptr = btrfs_item_ptr_offset(leaf, slot);
+ unsigned long end = ptr + btrfs_item_size_nr(leaf, slot);
+
+ if (btrfs_item_size_nr(leaf, slot) % sizeof(*dref) != 0) {
+ generic_err(leaf, slot,
+ "invalid item size, have %u expect aligned to %zu for key type %u",
+ btrfs_item_size_nr(leaf, slot),
+ sizeof(*dref), key->type);
+ }
+ if (!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize)) {
+ generic_err(leaf, slot,
+"invalid key objectid for shared block ref, have %llu expect aligned to %u",
+ key->objectid, leaf->fs_info->sectorsize);
+ return -EUCLEAN;
+ }
+ for (; ptr < end; ptr += sizeof(*dref)) {
+ u64 root_objectid;
+ u64 owner;
+ u64 offset;
+ u64 hash;
+
+ dref = (struct btrfs_extent_data_ref *)ptr;
+ root_objectid = btrfs_extent_data_ref_root(leaf, dref);
+ owner = btrfs_extent_data_ref_objectid(leaf, dref);
+ offset = btrfs_extent_data_ref_offset(leaf, dref);
+ hash = hash_extent_data_ref(root_objectid, owner, offset);
+ if (hash != key->offset) {
+ extent_err(leaf, slot,
+ "invalid extent data ref hash, item have 0x%016llx key have 0x%016llx",
+ hash, key->offset);
+ return -EUCLEAN;
+ }
+ if (!IS_ALIGNED(offset, leaf->fs_info->sectorsize)) {
+ extent_err(leaf, slot,
+ "invalid extent data backref offset, have %llu expect aligned to %u",
+ offset, leaf->fs_info->sectorsize);
+ }
+ }
+ return 0;
+}
+
/*
* Common point to switch the item-specific validation.
*/
@@ -1225,6 +1270,9 @@ static int check_leaf_item(struct extent_buffer *leaf,
case BTRFS_SHARED_BLOCK_REF_KEY:
ret = check_simple_keyed_refs(leaf, key, slot);
break;
+ case BTRFS_EXTENT_DATA_REF_KEY:
+ ret = check_extent_data_ref(leaf, key, slot);
+ break;
}
return ret;
}
--
2.22.0
^ permalink raw reply related [flat|nested] 9+ messages in thread