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authorEric Sandeen <sandeen@redhat.com>2008-01-08 18:33:20 -0500
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2008-01-08 19:10:36 -0500
commitcf0594625083111ae522496dc1c256f7476939c2 (patch)
treef83641f74c89fa4fb17adb2f216b074f2352639c
parent467bc461d2845f6a04b124bca1ae6ecc554e1ee5 (diff)
hfs: handle more on-disk corruptions without oopsing
hfs seems prone to bad things when it encounters on disk corruption. Many values are read from disk, and used as lengths to memcpy, as an example. This patch fixes up several of these problematic cases. o sanity check the on-disk maximum key lengths on mount (these are set to a defined value at mkfs time and shouldn't differ) o check on-disk node keylens against the maximum key length for each tree o fix hfs_btree_open so that going out via free_tree: doesn't wind up in hfs_releasepage, which wants to follow the very pointer we were trying to set up: HFS_SB(sb)->cat_tree = hfs_btree_open() ... failure gets to hfs_releasepage and tries to follow HFS_SB(sb)->cat_tree Tested with the fsfuzzer; it survives more than it used to. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--fs/hfs/bfind.c12
-rw-r--r--fs/hfs/brec.c15
-rw-r--r--fs/hfs/btree.c13
-rw-r--r--fs/hfs/hfs.h5
4 files changed, 42 insertions, 3 deletions
diff --git a/fs/hfs/bfind.c b/fs/hfs/bfind.c
index f13f1494d4fe..f8452a0eab56 100644
--- a/fs/hfs/bfind.c
+++ b/fs/hfs/bfind.c
@@ -52,6 +52,10 @@ int __hfs_brec_find(struct hfs_bnode *bnode, struct hfs_find_data *fd)
52 rec = (e + b) / 2; 52 rec = (e + b) / 2;
53 len = hfs_brec_lenoff(bnode, rec, &off); 53 len = hfs_brec_lenoff(bnode, rec, &off);
54 keylen = hfs_brec_keylen(bnode, rec); 54 keylen = hfs_brec_keylen(bnode, rec);
55 if (keylen == HFS_BAD_KEYLEN) {
56 res = -EINVAL;
57 goto done;
58 }
55 hfs_bnode_read(bnode, fd->key, off, keylen); 59 hfs_bnode_read(bnode, fd->key, off, keylen);
56 cmpval = bnode->tree->keycmp(fd->key, fd->search_key); 60 cmpval = bnode->tree->keycmp(fd->key, fd->search_key);
57 if (!cmpval) { 61 if (!cmpval) {
@@ -67,6 +71,10 @@ int __hfs_brec_find(struct hfs_bnode *bnode, struct hfs_find_data *fd)
67 if (rec != e && e >= 0) { 71 if (rec != e && e >= 0) {
68 len = hfs_brec_lenoff(bnode, e, &off); 72 len = hfs_brec_lenoff(bnode, e, &off);
69 keylen = hfs_brec_keylen(bnode, e); 73 keylen = hfs_brec_keylen(bnode, e);
74 if (keylen == HFS_BAD_KEYLEN) {
75 res = -EINVAL;
76 goto done;
77 }
70 hfs_bnode_read(bnode, fd->key, off, keylen); 78 hfs_bnode_read(bnode, fd->key, off, keylen);
71 } 79 }
72done: 80done:
@@ -198,6 +206,10 @@ int hfs_brec_goto(struct hfs_find_data *fd, int cnt)
198 206
199 len = hfs_brec_lenoff(bnode, fd->record, &off); 207 len = hfs_brec_lenoff(bnode, fd->record, &off);
200 keylen = hfs_brec_keylen(bnode, fd->record); 208 keylen = hfs_brec_keylen(bnode, fd->record);
209 if (keylen == HFS_BAD_KEYLEN) {
210 res = -EINVAL;
211 goto out;
212 }
201 fd->keyoffset = off; 213 fd->keyoffset = off;
202 fd->keylength = keylen; 214 fd->keylength = keylen;
203 fd->entryoffset = off + keylen; 215 fd->entryoffset = off + keylen;
diff --git a/fs/hfs/brec.c b/fs/hfs/brec.c
index 5c87cf4801fc..8626ee375ea8 100644
--- a/fs/hfs/brec.c
+++ b/fs/hfs/brec.c
@@ -44,10 +44,21 @@ u16 hfs_brec_keylen(struct hfs_bnode *node, u16 rec)
44 recoff = hfs_bnode_read_u16(node, node->tree->node_size - (rec + 1) * 2); 44 recoff = hfs_bnode_read_u16(node, node->tree->node_size - (rec + 1) * 2);
45 if (!recoff) 45 if (!recoff)
46 return 0; 46 return 0;
47 if (node->tree->attributes & HFS_TREE_BIGKEYS) 47 if (node->tree->attributes & HFS_TREE_BIGKEYS) {
48 retval = hfs_bnode_read_u16(node, recoff) + 2; 48 retval = hfs_bnode_read_u16(node, recoff) + 2;
49 else 49 if (retval > node->tree->max_key_len + 2) {
50 printk(KERN_ERR "hfs: keylen %d too large\n",
51 retval);
52 retval = HFS_BAD_KEYLEN;
53 }
54 } else {
50 retval = (hfs_bnode_read_u8(node, recoff) | 1) + 1; 55 retval = (hfs_bnode_read_u8(node, recoff) | 1) + 1;
56 if (retval > node->tree->max_key_len + 1) {
57 printk(KERN_ERR "hfs: keylen %d too large\n",
58 retval);
59 retval = HFS_BAD_KEYLEN;
60 }
61 }
51 } 62 }
52 return retval; 63 return retval;
53} 64}
diff --git a/fs/hfs/btree.c b/fs/hfs/btree.c
index 8a3a650abc87..31284c77bba8 100644
--- a/fs/hfs/btree.c
+++ b/fs/hfs/btree.c
@@ -81,6 +81,17 @@ struct hfs_btree *hfs_btree_open(struct super_block *sb, u32 id, btree_keycmp ke
81 goto fail_page; 81 goto fail_page;
82 if (!tree->node_count) 82 if (!tree->node_count)
83 goto fail_page; 83 goto fail_page;
84 if ((id == HFS_EXT_CNID) && (tree->max_key_len != HFS_MAX_EXT_KEYLEN)) {
85 printk(KERN_ERR "hfs: invalid extent max_key_len %d\n",
86 tree->max_key_len);
87 goto fail_page;
88 }
89 if ((id == HFS_CAT_CNID) && (tree->max_key_len != HFS_MAX_CAT_KEYLEN)) {
90 printk(KERN_ERR "hfs: invalid catalog max_key_len %d\n",
91 tree->max_key_len);
92 goto fail_page;
93 }
94
84 tree->node_size_shift = ffs(size) - 1; 95 tree->node_size_shift = ffs(size) - 1;
85 tree->pages_per_bnode = (tree->node_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; 96 tree->pages_per_bnode = (tree->node_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
86 97
@@ -89,9 +100,9 @@ struct hfs_btree *hfs_btree_open(struct super_block *sb, u32 id, btree_keycmp ke
89 return tree; 100 return tree;
90 101
91 fail_page: 102 fail_page:
92 tree->inode->i_mapping->a_ops = &hfs_aops;
93 page_cache_release(page); 103 page_cache_release(page);
94 free_tree: 104 free_tree:
105 tree->inode->i_mapping->a_ops = &hfs_aops;
95 iput(tree->inode); 106 iput(tree->inode);
96 kfree(tree); 107 kfree(tree);
97 return NULL; 108 return NULL;
diff --git a/fs/hfs/hfs.h b/fs/hfs/hfs.h
index 1445e3a56ed4..c6aae61adfe6 100644
--- a/fs/hfs/hfs.h
+++ b/fs/hfs/hfs.h
@@ -28,6 +28,8 @@
28#define HFS_MAX_NAMELEN 128 28#define HFS_MAX_NAMELEN 128
29#define HFS_MAX_VALENCE 32767U 29#define HFS_MAX_VALENCE 32767U
30 30
31#define HFS_BAD_KEYLEN 0xFF
32
31/* Meanings of the drAtrb field of the MDB, 33/* Meanings of the drAtrb field of the MDB,
32 * Reference: _Inside Macintosh: Files_ p. 2-61 34 * Reference: _Inside Macintosh: Files_ p. 2-61
33 */ 35 */
@@ -167,6 +169,9 @@ typedef union hfs_btree_key {
167 struct hfs_ext_key ext; 169 struct hfs_ext_key ext;
168} hfs_btree_key; 170} hfs_btree_key;
169 171
172#define HFS_MAX_CAT_KEYLEN (sizeof(struct hfs_cat_key) - sizeof(u8))
173#define HFS_MAX_EXT_KEYLEN (sizeof(struct hfs_ext_key) - sizeof(u8))
174
170typedef union hfs_btree_key btree_key; 175typedef union hfs_btree_key btree_key;
171 176
172struct hfs_extent { 177struct hfs_extent {