diff options
Diffstat (limited to 'fs/afs/dir.c')
| -rw-r--r-- | fs/afs/dir.c | 27 |
1 files changed, 19 insertions, 8 deletions
diff --git a/fs/afs/dir.c b/fs/afs/dir.c index 53f3917440e7..ecda0e6a9f7e 100644 --- a/fs/afs/dir.c +++ b/fs/afs/dir.c @@ -130,10 +130,11 @@ struct afs_lookup_cookie { /* * check that a directory page is valid */ -static inline bool afs_dir_check_page(struct inode *dir, struct page *page) +bool afs_dir_check_page(struct inode *dir, struct page *page) { struct afs_dir_page *dbuf; - loff_t latter; + struct afs_vnode *vnode = AFS_FS_I(dir); + loff_t latter, i_size, off; int tmp, qty; #if 0 @@ -150,8 +151,15 @@ static inline bool afs_dir_check_page(struct inode *dir, struct page *page) } #endif - /* determine how many magic numbers there should be in this page */ - latter = dir->i_size - page_offset(page); + /* Determine how many magic numbers there should be in this page, but + * we must take care because the directory may change size under us. + */ + off = page_offset(page); + i_size = i_size_read(dir); + if (i_size <= off) + goto checked; + + latter = i_size - off; if (latter >= PAGE_SIZE) qty = PAGE_SIZE; else @@ -162,13 +170,15 @@ static inline bool afs_dir_check_page(struct inode *dir, struct page *page) dbuf = page_address(page); for (tmp = 0; tmp < qty; tmp++) { if (dbuf->blocks[tmp].pagehdr.magic != AFS_DIR_MAGIC) { - printk("kAFS: %s(%lu): bad magic %d/%d is %04hx\n", + printk("kAFS: %s(%lx): bad magic %d/%d is %04hx\n", __func__, dir->i_ino, tmp, qty, ntohs(dbuf->blocks[tmp].pagehdr.magic)); + trace_afs_dir_check_failed(vnode, off, i_size); goto error; } } +checked: SetPageChecked(page); return true; @@ -183,6 +193,7 @@ error: static inline void afs_dir_put_page(struct page *page) { kunmap(page); + unlock_page(page); put_page(page); } @@ -197,9 +208,10 @@ static struct page *afs_dir_get_page(struct inode *dir, unsigned long index, page = read_cache_page(dir->i_mapping, index, afs_page_filler, key); if (!IS_ERR(page)) { + lock_page(page); kmap(page); if (unlikely(!PageChecked(page))) { - if (PageError(page) || !afs_dir_check_page(dir, page)) + if (PageError(page)) goto fail; } } @@ -384,8 +396,7 @@ out: */ static int afs_readdir(struct file *file, struct dir_context *ctx) { - return afs_dir_iterate(file_inode(file), - ctx, file->private_data); + return afs_dir_iterate(file_inode(file), ctx, file->private_data); } /* |