From eb626f49181bbff8bd9eed64c3544d57907fe91a Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Mon, 9 Sep 2013 16:41:54 -0400 Subject: [PATCH] Btrfs-progs: setup framework to corrupt specific fields of an inode A user reported a problem with his fs where he had a bogus isize on his directory. In order to make sure my patch for fsck fixes this properly I needed to be able to corrupt an inode like this, which is what this patch is for. Eventually I want to extend this to corrupt everything so we can integrate tests into btrfs-progs to run btrfsck against to make sure we don't regress on fixing things with btrfsck. Thanks, Signed-off-by: Josef Bacik Signed-off-by: David Sterba Signed-off-by: Chris Mason --- btrfs-corrupt-block.c | 125 +++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 118 insertions(+), 7 deletions(-) diff --git a/btrfs-corrupt-block.c b/btrfs-corrupt-block.c index 5c51305..5812a42 100644 --- a/btrfs-corrupt-block.c +++ b/btrfs-corrupt-block.c @@ -33,6 +33,8 @@ #include "version.h" #include "utils.h" +#define FIELD_BUF_LEN 80 + struct extent_buffer *debug_corrupt_block(struct btrfs_root *root, u64 bytenr, u32 blocksize, int copy) { @@ -97,6 +99,9 @@ static void print_usage(void) fprintf(stderr, "\t-E The whole extent tree to be corrupted\n"); fprintf(stderr, "\t-u Given chunk item to be corrupted\n"); fprintf(stderr, "\t-U The whole chunk tree to be corrupted\n"); + fprintf(stderr, "\t-i The inode item to corrupt (must also specify " + "the field to corrupt)\n"); + fprintf(stderr, "\t-f The field in the item to corrupt\n"); exit(1); } @@ -280,6 +285,83 @@ static void btrfs_corrupt_extent_tree(struct btrfs_trans_handle *trans, } } +enum btrfs_inode_field { + BTRFS_INODE_FIELD_ISIZE, + BTRFS_INODE_FIELD_BAD, +}; + +static enum btrfs_inode_field convert_field(char *field) +{ + if (!strncmp(field, "isize", FIELD_BUF_LEN)) + return BTRFS_INODE_FIELD_ISIZE; + return BTRFS_INODE_FIELD_BAD; +} + +static int corrupt_inode(struct btrfs_trans_handle *trans, + struct btrfs_root *root, u64 inode, char *field) +{ + struct btrfs_inode_item *ei; + struct btrfs_path *path; + struct btrfs_key key; + enum btrfs_inode_field corrupt_field = convert_field(field); + u64 bogus; + u64 orig; + int ret; + + if (corrupt_field == BTRFS_INODE_FIELD_BAD) { + fprintf(stderr, "Invalid field %s\n", field); + return -EINVAL; + } + + key.objectid = inode; + key.type = BTRFS_INODE_ITEM_KEY; + key.offset = (u64)-1; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + ret = btrfs_search_slot(trans, root, &key, path, 0, 1); + if (ret < 0) + goto out; + if (ret) { + if (!path->slots[0]) { + fprintf(stderr, "Couldn't find inode %Lu\n", inode); + ret = -ENOENT; + goto out; + } + path->slots[0]--; + ret = 0; + } + + btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); + if (key.objectid != inode) { + fprintf(stderr, "Couldn't find inode %Lu\n", inode); + ret = -ENOENT; + goto out; + } + + ei = btrfs_item_ptr(path->nodes[0], path->slots[0], + struct btrfs_inode_item); + switch (corrupt_field) { + case BTRFS_INODE_FIELD_ISIZE: + orig = btrfs_inode_size(path->nodes[0], ei); + do { + bogus = rand(); + } while (bogus == orig); + + btrfs_set_inode_size(path->nodes[0], ei, bogus); + break; + default: + ret = -EINVAL; + break; + } + btrfs_mark_buffer_dirty(path->nodes[0]); +out: + btrfs_free_path(path); + return ret; +} + static struct option long_options[] = { /* { "byte-count", 1, NULL, 'b' }, */ { "logical", 1, NULL, 'l' }, @@ -290,6 +372,8 @@ static struct option long_options[] = { { "keys", 0, NULL, 'k' }, { "chunk-record", 0, NULL, 'u' }, { "chunk-tree", 0, NULL, 'U' }, + { "inode", 1, NULL, 'i'}, + { "field", 1, NULL, 'f'}, { 0, 0, 0, 0} }; @@ -450,12 +534,15 @@ int main(int ac, char **av) int corrupt_block_keys = 0; int chunk_rec = 0; int chunk_tree = 0; + u64 inode = 0; + char field[FIELD_BUF_LEN]; + field[0] = '\0'; srand(128); while(1) { int c; - c = getopt_long(ac, av, "l:c:b:eEkuU", long_options, + c = getopt_long(ac, av, "l:c:b:eEkuUi:f:", long_options, &option_index); if (c < 0) break; @@ -465,7 +552,7 @@ int main(int ac, char **av) break; case 'c': copy = atoi(optarg); - if (copy == 0) { + if (copy <= 0) { fprintf(stderr, "invalid copy number\n"); print_usage(); @@ -493,6 +580,16 @@ int main(int ac, char **av) break; case 'U': chunk_tree = 1; + case 'i': + inode = atoll(optarg); + if (inode == 0) { + fprintf(stderr, + "invalid inode number\n"); + print_usage(); + } + break; + case 'f': + strncpy(field, optarg, FIELD_BUF_LEN); break; default: print_usage(); @@ -501,11 +598,6 @@ int main(int ac, char **av) ac = ac - optind; if (ac == 0) print_usage(); - if (logical == (u64)-1 && !(extent_tree || chunk_tree)) - print_usage(); - if (copy < 0) - print_usage(); - dev = av[optind]; radix_tree_init(); @@ -518,6 +610,9 @@ int main(int ac, char **av) } if (extent_rec) { struct btrfs_trans_handle *trans; + + if (logical == (u64)-1) + print_usage(); trans = btrfs_start_transaction(root, 1); ret = corrupt_extent (trans, root, logical, 0); btrfs_commit_transaction(trans, root); @@ -536,6 +631,8 @@ int main(int ac, char **av) struct btrfs_path *path; int del; + if (logical == (u64)-1) + print_usage(); del = rand() % 3; path = btrfs_alloc_path(); @@ -561,6 +658,20 @@ int main(int ac, char **av) btrfs_commit_transaction(trans, root); goto out_close; } + if (inode) { + struct btrfs_trans_handle *trans; + + if (!strlen(field)) + print_usage(); + printf("corrupting inode\n"); + trans = btrfs_start_transaction(root, 1); + ret = corrupt_inode(trans, root, inode, field); + btrfs_commit_transaction(trans, root); + goto out_close; + } + + if (logical == (u64)-1) + print_usage(); if (bytes == 0) bytes = root->sectorsize; -- 2.7.4