btrfs: fix null pointer deference at btrfs_sysfs_add_one+0x105

[~andy/linux] / fs / btrfs / compression.c

diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 1499b27b41863e7dfbbe7da134b1a7fb66dece34..ed1ff1cb101771c1b8c52abec38905cb68c3f107 100644 (file)
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -128,11 +128,10 @@ static int check_compressed_csum(struct inode *inode,
                kunmap_atomic(kaddr);
 
                if (csum != *cb_sum) {
-                       printk(KERN_INFO "btrfs csum failed ino %llu "
-                              "extent %llu csum %u "
-                              "wanted %u mirror %d\n",
-                              btrfs_ino(inode), disk_start, csum, *cb_sum,
-                              cb->mirror_num);
+                       btrfs_info(BTRFS_I(inode)->root->fs_info,
+                          "csum failed ino %llu extent %llu csum %u wanted %u mirror %d",
+                          btrfs_ino(inode), disk_start, csum, *cb_sum,
+                          cb->mirror_num);
                        ret = -EIO;
                        goto fail;
                }
@@ -412,7 +411,8 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start,
                        bio_add_page(bio, page, PAGE_CACHE_SIZE, 0);
                }
                if (bytes_left < PAGE_CACHE_SIZE) {
-                       printk("bytes left %lu compress len %lu nr %lu\n",
+                       btrfs_info(BTRFS_I(inode)->root->fs_info,
+                                       "bytes left %lu compress len %lu nr %lu",
                               bytes_left, cb->compressed_len, cb->nr_pages);
                }
                bytes_left -= PAGE_CACHE_SIZE;
@@ -1011,6 +1011,8 @@ int btrfs_decompress_buf2page(char *buf, unsigned long buf_start,
                bytes = min(bytes, working_bytes);
                kaddr = kmap_atomic(page_out);
                memcpy(kaddr + *pg_offset, buf + buf_offset, bytes);
+               if (*pg_index == (vcnt - 1) && *pg_offset == 0)
+                       memset(kaddr + bytes, 0, PAGE_CACHE_SIZE - bytes);
                kunmap_atomic(kaddr);
                flush_dcache_page(page_out);