From 6b82ce8d824bd46053e46a895876cde39d9026e4 Mon Sep 17 00:00:00 2001 From: liubo Date: Wed, 26 Jan 2011 06:21:39 +0000 Subject: [PATCH] btrfs: fix uncheck memory allocation in btrfs_submit_compressed_read btrfs_submit_compressed_read() is lack of memory allocation checks and corresponding error route. After this fix, if it comes to "no memory" case, errno will be returned to userland step by step, and tell users this operation cannot go on. Signed-off-by: Liu Bo Signed-off-by: Chris Mason --- fs/btrfs/compression.c | 25 +++++++++++++++++++++++-- fs/btrfs/extent_io.c | 4 ++-- 2 files changed, 25 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c index f745287fbf2e..3a932f183da1 100644 --- a/fs/btrfs/compression.c +++ b/fs/btrfs/compression.c @@ -562,7 +562,7 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, u64 em_len; u64 em_start; struct extent_map *em; - int ret; + int ret = -ENOMEM; u32 *sums; tree = &BTRFS_I(inode)->io_tree; @@ -577,6 +577,9 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, compressed_len = em->block_len; cb = kmalloc(compressed_bio_size(root, compressed_len), GFP_NOFS); + if (!cb) + goto out; + atomic_set(&cb->pending_bios, 0); cb->errors = 0; cb->inode = inode; @@ -597,13 +600,18 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, nr_pages = (compressed_len + PAGE_CACHE_SIZE - 1) / PAGE_CACHE_SIZE; - cb->compressed_pages = kmalloc(sizeof(struct page *) * nr_pages, + cb->compressed_pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS); + if (!cb->compressed_pages) + goto fail1; + bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev; for (page_index = 0; page_index < nr_pages; page_index++) { cb->compressed_pages[page_index] = alloc_page(GFP_NOFS | __GFP_HIGHMEM); + if (!cb->compressed_pages[page_index]) + goto fail2; } cb->nr_pages = nr_pages; @@ -614,6 +622,8 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, cb->len = uncompressed_len; comp_bio = compressed_bio_alloc(bdev, cur_disk_byte, GFP_NOFS); + if (!comp_bio) + goto fail2; comp_bio->bi_private = cb; comp_bio->bi_end_io = end_compressed_bio_read; atomic_inc(&cb->pending_bios); @@ -681,6 +691,17 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, bio_put(comp_bio); return 0; + +fail2: + for (page_index = 0; page_index < nr_pages; page_index++) + free_page((unsigned long)cb->compressed_pages[page_index]); + + kfree(cb->compressed_pages); +fail1: + kfree(cb); +out: + free_extent_map(em); + return ret; } static struct list_head comp_idle_workspace[BTRFS_COMPRESS_TYPES]; diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 8b8d3d99ae68..6411ed6ca449 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -1865,7 +1865,7 @@ static int submit_one_bio(int rw, struct bio *bio, int mirror_num, bio_get(bio); if (tree->ops && tree->ops->submit_bio_hook) - tree->ops->submit_bio_hook(page->mapping->host, rw, bio, + ret = tree->ops->submit_bio_hook(page->mapping->host, rw, bio, mirror_num, bio_flags, start); else submit_bio(rw, bio); @@ -2126,7 +2126,7 @@ int extent_read_full_page(struct extent_io_tree *tree, struct page *page, ret = __extent_read_full_page(tree, page, get_extent, &bio, 0, &bio_flags); if (bio) - submit_one_bio(READ, bio, 0, bio_flags); + ret = submit_one_bio(READ, bio, 0, bio_flags); return ret; } -- 2.20.1