diff options
| -rw-r--r-- | fs/afs/dir.c | 27 | ||||
| -rw-r--r-- | fs/afs/file.c | 5 | ||||
| -rw-r--r-- | fs/afs/internal.h | 1 | ||||
| -rw-r--r-- | include/trace/events/afs.h | 21 |
4 files changed, 46 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); } /* diff --git a/fs/afs/file.c b/fs/afs/file.c index 1f26ac9f816d..5786f68f87f1 100644 --- a/fs/afs/file.c +++ b/fs/afs/file.c @@ -232,6 +232,11 @@ int afs_page_filler(void *data, struct page *page) * page */ ret = afs_fetch_data(vnode, key, req); afs_put_read(req); + + if (ret >= 0 && S_ISDIR(inode->i_mode) && + !afs_dir_check_page(inode, page)) + ret = -EIO; + if (ret < 0) { if (ret == -ENOENT) { _debug("got NOENT from server" diff --git a/fs/afs/internal.h b/fs/afs/internal.h index aad12546e0ea..6aa6e9957c44 100644 --- a/fs/afs/internal.h +++ b/fs/afs/internal.h @@ -622,6 +622,7 @@ extern bool afs_cm_incoming_call(struct afs_call *); /* * dir.c */ +extern bool afs_dir_check_page(struct inode *, struct page *); extern const struct inode_operations afs_dir_inode_operations; extern const struct dentry_operations afs_fs_dentry_operations; extern const struct file_operations afs_dir_file_operations; diff --git a/include/trace/events/afs.h b/include/trace/events/afs.h index c780f4c39a53..9cfb7657b72c 100644 --- a/include/trace/events/afs.h +++ b/include/trace/events/afs.h @@ -381,6 +381,27 @@ TRACE_EVENT(afs_sent_pages, __entry->cursor, __entry->ret) ); +TRACE_EVENT(afs_dir_check_failed, + TP_PROTO(struct afs_vnode *vnode, loff_t off, loff_t i_size), + + TP_ARGS(vnode, off, i_size), + + TP_STRUCT__entry( + __field(struct afs_vnode *, vnode ) + __field(loff_t, off ) + __field(loff_t, i_size ) + ), + + TP_fast_assign( + __entry->vnode = vnode; + __entry->off = off; + __entry->i_size = i_size; + ), + + TP_printk("vn=%p %llx/%llx", + __entry->vnode, __entry->off, __entry->i_size) + ); + #endif /* _TRACE_AFS_H */ /* This part must be outside protection */ |