btrfs-progs: lowmem check: Fix false alert about file extent interrupt
[platform/upstream/btrfs-progs.git] / cmds-check.c
index c94216b..23adc03 100644 (file)
@@ -1512,13 +1512,19 @@ static int process_dir_item(struct extent_buffer *eb,
                filetype = btrfs_dir_type(eb, di);
 
                rec->found_size += name_len;
-               if (name_len <= BTRFS_NAME_LEN) {
+               if (cur + sizeof(*di) + name_len > total ||
+                   name_len > BTRFS_NAME_LEN) {
+                       error = REF_ERR_NAME_TOO_LONG;
+
+                       if (cur + sizeof(*di) > total)
+                               break;
+                       len = min_t(u32, total - cur - sizeof(*di),
+                                   BTRFS_NAME_LEN);
+               } else {
                        len = name_len;
                        error = 0;
-               } else {
-                       len = BTRFS_NAME_LEN;
-                       error = REF_ERR_NAME_TOO_LONG;
                }
+
                read_extent_buffer(eb, namebuf, (unsigned long)(di + 1), len);
 
                if (location.type == BTRFS_INODE_ITEM_KEY) {
@@ -1569,13 +1575,22 @@ static int process_inode_ref(struct extent_buffer *eb,
        while (cur < total) {
                name_len = btrfs_inode_ref_name_len(eb, ref);
                index = btrfs_inode_ref_index(eb, ref);
-               if (name_len <= BTRFS_NAME_LEN) {
+
+               /* inode_ref + namelen should not cross item boundary */
+               if (cur + sizeof(*ref) + name_len > total ||
+                   name_len > BTRFS_NAME_LEN) {
+                       if (total < cur + sizeof(*ref))
+                               break;
+
+                       /* Still try to read out the remaining part */
+                       len = min_t(u32, total - cur - sizeof(*ref),
+                                   BTRFS_NAME_LEN);
+                       error = REF_ERR_NAME_TOO_LONG;
+               } else {
                        len = name_len;
                        error = 0;
-               } else {
-                       len = BTRFS_NAME_LEN;
-                       error = REF_ERR_NAME_TOO_LONG;
                }
+
                read_extent_buffer(eb, namebuf, (unsigned long)(ref + 1), len);
                add_inode_backref(inode_cache, key->objectid, key->offset,
                                  index, namebuf, len, 0, key->type, error);
@@ -1868,6 +1883,11 @@ static int update_nodes_refs(struct btrfs_root *root, u64 bytenr,
 static int check_inode_item(struct btrfs_root *root, struct btrfs_path *path,
                            unsigned int ext_ref);
 
+/*
+ * Returns >0  Found error, not fatal, should continue
+ * Returns <0  Fatal error, must exit the whole check
+ * Returns 0   No errors found
+ */
 static int process_one_leaf_v2(struct btrfs_root *root, struct btrfs_path *path,
                               struct node_refs *nrefs, int *level, int ext_ref)
 {
@@ -1937,13 +1957,8 @@ again:
        }
 out:
        err &= ~LAST_ITEM;
-       /*
-        * Convert any error bitmap to -EIO, as we should avoid
-        * mixing positive and negative return value to represent
-        * error
-        */
        if (err && !ret)
-               ret = -EIO;
+               ret = err;
        return ret;
 }
 
@@ -2185,6 +2200,7 @@ static int walk_down_tree(struct btrfs_root *root, struct btrfs_path *path,
 
                ret = check_child_node(cur, path->slots[*level], next);
                if (ret) {
+                       free_extent_buffer(next);
                        err = ret;
                        goto out;
                }
@@ -2212,6 +2228,11 @@ out:
 static int check_inode_item(struct btrfs_root *root, struct btrfs_path *path,
                            unsigned int ext_ref);
 
+/*
+ * Returns >0  Found error, should continue
+ * Returns <0  Fatal error, must exit the whole check
+ * Returns 0   No errors found
+ */
 static int walk_down_tree_v2(struct btrfs_root *root, struct btrfs_path *path,
                             int *level, struct node_refs *nrefs, int ext_ref)
 {
@@ -2661,6 +2682,7 @@ static int repair_inode_backrefs(struct btrfs_root *root,
                        repaired++;
                        list_del(&backref->list);
                        free(backref);
+                       continue;
                }
 
                if (!delete && !backref->found_dir_index &&
@@ -2671,12 +2693,12 @@ static int repair_inode_backrefs(struct btrfs_root *root,
                                break;
                        repaired++;
                        if (backref->found_dir_item &&
-                           backref->found_dir_index &&
                            backref->found_dir_index) {
                                if (!backref->errors &&
                                    backref->found_inode_ref) {
                                        list_del(&backref->list);
                                        free(backref);
+                                       continue;
                                }
                        }
                }
@@ -4219,16 +4241,22 @@ static int find_dir_item(struct btrfs_root *root, struct btrfs_key *ref_key,
                if (imode_to_type(mode) != filetype)
                        goto next;
 
-               if (name_len <= BTRFS_NAME_LEN) {
-                       len = name_len;
-               } else {
-                       len = BTRFS_NAME_LEN;
+               if (cur + sizeof(*di) + name_len > total ||
+                   name_len > BTRFS_NAME_LEN) {
                        warning("root %llu %s[%llu %llu] name too long %u, trimmed",
-                       root->objectid,
-                       key->type == BTRFS_DIR_ITEM_KEY ?
-                       "DIR_ITEM" : "DIR_INDEX",
-                       key->objectid, key->offset, name_len);
+                               root->objectid,
+                               key->type == BTRFS_DIR_ITEM_KEY ?
+                               "DIR_ITEM" : "DIR_INDEX",
+                               key->objectid, key->offset, name_len);
+
+                       if (cur + sizeof(*di) > total)
+                               break;
+                       len = min_t(u32, total - cur - sizeof(*di),
+                                   BTRFS_NAME_LEN);
+               } else {
+                       len = name_len;
                }
+
                read_extent_buffer(node, namebuf, (unsigned long)(di + 1), len);
                if (len != namelen || strncmp(namebuf, name, len))
                        goto next;
@@ -4289,12 +4317,16 @@ next:
 
        index = btrfs_inode_ref_index(node, ref);
        name_len = btrfs_inode_ref_name_len(node, ref);
-       if (name_len <= BTRFS_NAME_LEN) {
-               len = name_len;
-       } else {
-               len = BTRFS_NAME_LEN;
+       if (cur + sizeof(*ref) + name_len > total ||
+           name_len > BTRFS_NAME_LEN) {
                warning("root %llu INODE_REF[%llu %llu] name too long",
                        root->objectid, ref_key->objectid, ref_key->offset);
+
+               if (total < cur + sizeof(*ref))
+                       goto out;
+               len = min_t(u32, total - cur - sizeof(*ref), BTRFS_NAME_LEN);
+       } else {
+               len = name_len;
        }
 
        read_extent_buffer(node, namebuf, (unsigned long)(ref + 1), len);
@@ -4327,6 +4359,7 @@ next:
        if (cur < total)
                goto next;
 
+out:
        return err;
 }
 
@@ -4464,16 +4497,22 @@ static int find_inode_ref(struct btrfs_root *root, struct btrfs_key *key,
                if (index != (u64)-1 && index != ref_index)
                        goto next_ref;
 
-               if (ref_namelen <= BTRFS_NAME_LEN) {
-                       len = ref_namelen;
-               } else {
-                       len = BTRFS_NAME_LEN;
+               if (cur + sizeof(*ref) + ref_namelen > total ||
+                   ref_namelen > BTRFS_NAME_LEN) {
                        warning("root %llu INODE %s[%llu %llu] name too long",
                                root->objectid,
                                key->type == BTRFS_INODE_REF_KEY ?
                                        "REF" : "EXTREF",
                                key->objectid, key->offset);
+
+                       if (cur + sizeof(*ref) > total)
+                               break;
+                       len = min_t(u32, total - cur - sizeof(*ref),
+                                   BTRFS_NAME_LEN);
+               } else {
+                       len = ref_namelen;
                }
+
                read_extent_buffer(node, ref_namebuf, (unsigned long)(ref + 1),
                                   len);
 
@@ -4605,15 +4644,20 @@ static int check_dir_item(struct btrfs_root *root, struct btrfs_key *key,
                              key->objectid, key->offset, data_len);
 
                name_len = btrfs_dir_name_len(node, di);
-               if (name_len <= BTRFS_NAME_LEN) {
-                       len = name_len;
-               } else {
-                       len = BTRFS_NAME_LEN;
+               if (cur + sizeof(*di) + name_len > total ||
+                   name_len > BTRFS_NAME_LEN) {
                        warning("root %llu %s[%llu %llu] name too long",
                                root->objectid,
                                key->type == BTRFS_DIR_ITEM_KEY ?
                                "DIR_ITEM" : "DIR_INDEX",
                                key->objectid, key->offset);
+
+                       if (cur + sizeof(*di) > total)
+                               break;
+                       len = min_t(u32, total - cur - sizeof(*di),
+                                   BTRFS_NAME_LEN);
+               } else {
+                       len = name_len;
                }
                (*size) += name_len;
 
@@ -4699,25 +4743,41 @@ static int check_file_extent(struct btrfs_root *root, struct btrfs_key *fkey,
        u64 disk_bytenr;
        u64 disk_num_bytes;
        u64 extent_num_bytes;
-       u64 found;
+       u64 extent_offset;
+       u64 csum_found;         /* In byte size, sectorsize aligned */
+       u64 search_start;       /* Logical range start we search for csum */
+       u64 search_len;         /* Logical range len we search for csum */
        unsigned int extent_type;
        unsigned int is_hole;
+       int compressed = 0;
        int ret;
        int err = 0;
 
        fi = btrfs_item_ptr(node, slot, struct btrfs_file_extent_item);
 
+       /* Check inline extent */
        extent_type = btrfs_file_extent_type(node, fi);
-       /* Skip if file extent is inline */
        if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
                struct btrfs_item *e = btrfs_item_nr(slot);
                u32 item_inline_len;
 
                item_inline_len = btrfs_file_extent_inline_item_len(node, e);
                extent_num_bytes = btrfs_file_extent_inline_len(node, slot, fi);
-               if (extent_num_bytes == 0 ||
-                   extent_num_bytes != item_inline_len)
+               compressed = btrfs_file_extent_compression(node, fi);
+               if (extent_num_bytes == 0) {
+                       error(
+               "root %llu EXTENT_DATA[%llu %llu] has empty inline extent",
+                               root->objectid, fkey->objectid, fkey->offset);
                        err |= FILE_EXTENT_ERROR;
+               }
+               if (!compressed && extent_num_bytes != item_inline_len) {
+                       error(
+               "root %llu EXTENT_DATA[%llu %llu] wrong inline size, have: %llu, expected: %u",
+                               root->objectid, fkey->objectid, fkey->offset,
+                               extent_num_bytes, item_inline_len);
+                       err |= FILE_EXTENT_ERROR;
+               }
+               *end += extent_num_bytes;
                *size += extent_num_bytes;
                return err;
        }
@@ -4735,32 +4795,49 @@ static int check_file_extent(struct btrfs_root *root, struct btrfs_key *fkey,
        disk_bytenr = btrfs_file_extent_disk_bytenr(node, fi);
        disk_num_bytes = btrfs_file_extent_disk_num_bytes(node, fi);
        extent_num_bytes = btrfs_file_extent_num_bytes(node, fi);
+       extent_offset = btrfs_file_extent_offset(node, fi);
+       compressed = btrfs_file_extent_compression(node, fi);
        is_hole = (disk_bytenr == 0) && (disk_num_bytes == 0);
 
-       /* Check EXTENT_DATA datasum */
-       ret = count_csum_range(root, disk_bytenr, disk_num_bytes, &found);
-       if (found > 0 && nodatasum) {
+       /*
+        * Check EXTENT_DATA csum
+        *
+        * For plain (uncompressed) extent, we should only check the range
+        * we're referring to, as it's possible that part of prealloc extent
+        * has been written, and has csum:
+        *
+        * |<--- Original large preallocated extent A ---->|
+        * |<- Prealloc File Extent ->|<- Regular Extent ->|
+        *      No csum                         Has csum
+        *
+        * For compressed extent, we should check the whole range.
+        */
+       if (!compressed) {
+               search_start = disk_bytenr + extent_offset;
+               search_len = extent_num_bytes;
+       } else {
+               search_start = disk_bytenr;
+               search_len = disk_num_bytes;
+       }
+       ret = count_csum_range(root, search_start, search_len, &csum_found);
+       if (csum_found > 0 && nodatasum) {
                err |= ODD_CSUM_ITEM;
                error("root %llu EXTENT_DATA[%llu %llu] nodatasum shouldn't have datasum",
                      root->objectid, fkey->objectid, fkey->offset);
        } else if (extent_type == BTRFS_FILE_EXTENT_REG && !nodatasum &&
-                  !is_hole &&
-                  (ret < 0 || found == 0 || found < disk_num_bytes)) {
+                  !is_hole && (ret < 0 || csum_found < search_len)) {
                err |= CSUM_ITEM_MISSING;
-               error("root %llu EXTENT_DATA[%llu %llu] datasum missing",
-                     root->objectid, fkey->objectid, fkey->offset);
-       } else if (extent_type == BTRFS_FILE_EXTENT_PREALLOC && found > 0) {
+               error("root %llu EXTENT_DATA[%llu %llu] csum missing, have: %llu, expected: %llu",
+                     root->objectid, fkey->objectid, fkey->offset,
+                     csum_found, search_len);
+       } else if (extent_type == BTRFS_FILE_EXTENT_PREALLOC && csum_found > 0) {
                err |= ODD_CSUM_ITEM;
-               error("root %llu EXTENT_DATA[%llu %llu] prealloc shouldn't have datasum",
-                     root->objectid, fkey->objectid, fkey->offset);
+               error("root %llu EXTENT_DATA[%llu %llu] prealloc shouldn't have csum, but has: %llu",
+                     root->objectid, fkey->objectid, fkey->offset, csum_found);
        }
 
        /* Check EXTENT_DATA hole */
-       if (no_holes && is_hole) {
-               err |= FILE_EXTENT_ERROR;
-               error("root %llu EXTENT_DATA[%llu %llu] shouldn't be hole",
-                     root->objectid, fkey->objectid, fkey->offset);
-       } else if (!no_holes && *end != fkey->offset) {
+       if (!no_holes && *end != fkey->offset) {
                err |= FILE_EXTENT_ERROR;
                error("root %llu EXTENT_DATA[%llu %llu] interrupt",
                      root->objectid, fkey->objectid, fkey->offset);
@@ -4961,6 +5038,8 @@ static int check_fs_first_inode(struct btrfs_root *root, unsigned int ext_ref)
        if (ret > 0) {
                ret = 0;
                err |= INODE_ITEM_MISSING;
+               error("first inode item of root %llu is missing",
+                     root->objectid);
        }
 
        err |= check_inode_item(root, &path, ext_ref);
@@ -4986,8 +5065,9 @@ static int check_fs_root_v2(struct btrfs_root *root, unsigned int ext_ref)
        struct btrfs_path path;
        struct node_refs nrefs;
        struct btrfs_root_item *root_item = &root->root_item;
-       int ret, wret;
+       int ret;
        int level;
+       int err = 0;
 
        /*
         * We need to manually check the first inode item(256)
@@ -5021,17 +5101,21 @@ static int check_fs_root_v2(struct btrfs_root *root, unsigned int ext_ref)
        }
 
        while (1) {
-               wret = walk_down_tree_v2(root, &path, &level, &nrefs, ext_ref);
-               if (wret < 0)
-                       ret = wret;
-               if (wret != 0)
+               ret = walk_down_tree_v2(root, &path, &level, &nrefs, ext_ref);
+               err |= !!ret;
+
+               /* if ret is negative, walk shall stop */
+               if (ret < 0) {
+                       ret = err;
                        break;
+               }
 
-               wret = walk_up_tree_v2(root, &path, &level);
-               if (wret < 0)
-                       ret = wret;
-               if (wret != 0)
+               ret = walk_up_tree_v2(root, &path, &level);
+               if (ret != 0) {
+                       /* Normal exit, reset ret to err */
+                       ret = err;
                        break;
+               }
        }
 
 out:
@@ -5981,6 +6065,7 @@ static int add_extent_rec_nolookup(struct cache_tree *extent_cache,
        struct extent_record *rec;
        int ret = 0;
 
+       BUG_ON(tmpl->max_size == 0);
        rec = malloc(sizeof(*rec));
        if (!rec)
                return -ENOMEM;
@@ -6144,6 +6229,7 @@ static int add_tree_backref(struct cache_tree *extent_cache, u64 bytenr,
                tmpl.start = bytenr;
                tmpl.nr = 1;
                tmpl.metadata = 1;
+               tmpl.max_size = 1;
 
                ret = add_extent_rec_nolookup(extent_cache, &tmpl);
                if (ret)
@@ -6784,14 +6870,16 @@ static int process_extent_item(struct btrfs_root *root,
                        ret = add_tree_backref(extent_cache, key.objectid,
                                        0, offset, 0);
                        if (ret < 0)
-                               error("add_tree_backref failed: %s",
+                               error(
+                       "add_tree_backref failed (extent items tree block): %s",
                                      strerror(-ret));
                        break;
                case BTRFS_SHARED_BLOCK_REF_KEY:
                        ret = add_tree_backref(extent_cache, key.objectid,
                                        offset, 0, 0);
                        if (ret < 0)
-                               error("add_tree_backref failed: %s",
+                               error(
+                       "add_tree_backref failed (extent items shared block): %s",
                                      strerror(-ret));
                        break;
                case BTRFS_EXTENT_DATA_REF_KEY:
@@ -7705,7 +7793,8 @@ static int run_next_block(struct btrfs_root *root,
                                ret = add_tree_backref(extent_cache,
                                                key.objectid, 0, key.offset, 0);
                                if (ret < 0)
-                                       error("add_tree_backref failed: %s",
+                                       error(
+                               "add_tree_backref failed (leaf tree block): %s",
                                              strerror(-ret));
                                continue;
                        }
@@ -7713,7 +7802,8 @@ static int run_next_block(struct btrfs_root *root,
                                ret = add_tree_backref(extent_cache,
                                                key.objectid, key.offset, 0, 0);
                                if (ret < 0)
-                                       error("add_tree_backref failed: %s",
+                                       error(
+                               "add_tree_backref failed (leaf shared block): %s",
                                              strerror(-ret));
                                continue;
                        }
@@ -7818,7 +7908,8 @@ static int run_next_block(struct btrfs_root *root,
                        ret = add_tree_backref(extent_cache, ptr, parent,
                                        owner, 1);
                        if (ret < 0) {
-                               error("add_tree_backref failed: %s",
+                               error(
+                               "add_tree_backref failed (non-leaf block): %s",
                                      strerror(-ret));
                                continue;
                        }
@@ -9924,6 +10015,8 @@ out:
        free_extent_cache_tree(&pending);
        free_extent_cache_tree(&reada);
        free_extent_cache_tree(&nodes);
+       free_root_item_list(&normal_trees);
+       free_root_item_list(&dropping_trees);
        return ret;
 loop:
        free_corrupt_blocks_tree(root->fs_info->corrupt_blocks);
@@ -10181,10 +10274,8 @@ static int check_extent_data_item(struct btrfs_root *root,
        dbref_key.offset = btrfs_file_extent_disk_num_bytes(eb, fi);
 
        ret = btrfs_search_slot(NULL, extent_root, &dbref_key, &path, 0, 0);
-       if (ret) {
-               err |= BACKREF_MISSING;
-               goto error;
-       }
+       if (ret)
+               goto out;
 
        leaf = path.nodes[0];
        slot = path.slots[0];
@@ -10225,11 +10316,10 @@ static int check_extent_data_item(struct btrfs_root *root,
                ptr += btrfs_extent_inline_ref_size(type);
        }
 
-       /* Didn't found inlined data backref, try EXTENT_DATA_REF_KEY */
        if (!found_dbackref) {
                btrfs_release_path(&path);
 
-               btrfs_init_path(&path);
+               /* Didn't find inlined data backref, try EXTENT_DATA_REF_KEY */
                dbref_key.objectid = btrfs_file_extent_disk_bytenr(eb, fi);
                dbref_key.type = BTRFS_EXTENT_DATA_REF_KEY;
                dbref_key.offset = hash_extent_data_ref(root->objectid,
@@ -10237,13 +10327,32 @@ static int check_extent_data_item(struct btrfs_root *root,
 
                ret = btrfs_search_slot(NULL, root->fs_info->extent_root,
                                        &dbref_key, &path, 0, 0);
-               if (!ret)
+               if (!ret) {
+                       found_dbackref = 1;
+                       goto out;
+               }
+
+               btrfs_release_path(&path);
+
+               /*
+                * Neither inlined nor EXTENT_DATA_REF found, try
+                * SHARED_DATA_REF as last chance.
+                */
+               dbref_key.objectid = disk_bytenr;
+               dbref_key.type = BTRFS_SHARED_DATA_REF_KEY;
+               dbref_key.offset = eb->start;
+
+               ret = btrfs_search_slot(NULL, root->fs_info->extent_root,
+                                       &dbref_key, &path, 0, 0);
+               if (!ret) {
                        found_dbackref = 1;
+                       goto out;
+               }
        }
 
+out:
        if (!found_dbackref)
                err |= BACKREF_MISSING;
-error:
        btrfs_release_path(&path);
        if (err & BACKREF_MISSING) {
                error("data extent[%llu %llu] backref lost",
@@ -10718,13 +10827,20 @@ static int check_extent_item(struct btrfs_fs_info *fs_info,
        }
        end = (unsigned long)ei + item_size;
 
-       if (ptr >= end) {
+next:
+       /* Reached extent item end normally */
+       if (ptr == end)
+               goto out;
+
+       /* Beyond extent item end, wrong item size */
+       if (ptr > end) {
                err |= ITEM_SIZE_MISMATCH;
+               error("extent item at bytenr %llu slot %d has wrong size",
+                       eb->start, slot);
                goto out;
        }
 
        /* Now check every backref in this extent item */
-next:
        iref = (struct btrfs_extent_inline_ref *)ptr;
        type = btrfs_extent_inline_ref_type(eb, iref);
        offset = btrfs_extent_inline_ref_offset(eb, iref);
@@ -10761,8 +10877,7 @@ next:
        }
 
        ptr += btrfs_extent_inline_ref_size(type);
-       if (ptr < end)
-               goto next;
+       goto next;
 
 out:
        return err;