From: Alan Cox Date: Thu, 20 Dec 2012 23:05:24 +0000 (-0800) Subject: hfsplus: avoid crash on failed block map free X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=5daa669c80c121ab75ecdf1c8e2df52f072fd25e;p=openwrt%2Fstaging%2Fblogic.git hfsplus: avoid crash on failed block map free If the read fails we kmap an error code. This doesn't end well. Instead print a critical error and pray. This mirrors the rest of the fs behaviour with critical error cases. Acked-by: Vyacheslav Dubeyko Signed-off-by: Alan Cox Signed-off-by: Vyacheslav Dubeyko Cc: Al Viro Cc: Christoph Hellwig Cc: Jan Kara Acked-by: Hin-Tak Leung Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/fs/hfsplus/bitmap.c b/fs/hfsplus/bitmap.c index 4cfbe2edd296..6feefc0cb48a 100644 --- a/fs/hfsplus/bitmap.c +++ b/fs/hfsplus/bitmap.c @@ -176,12 +176,14 @@ int hfsplus_block_free(struct super_block *sb, u32 offset, u32 count) dprint(DBG_BITMAP, "block_free: %u,%u\n", offset, count); /* are all of the bits in range? */ if ((offset + count) > sbi->total_blocks) - return -2; + return -ENOENT; mutex_lock(&sbi->alloc_mutex); mapping = sbi->alloc_file->i_mapping; pnr = offset / PAGE_CACHE_BITS; page = read_mapping_page(mapping, pnr, NULL); + if (IS_ERR(page)) + goto kaboom; pptr = kmap(page); curr = pptr + (offset & (PAGE_CACHE_BITS - 1)) / 32; end = pptr + PAGE_CACHE_BITS / 32; @@ -214,6 +216,8 @@ int hfsplus_block_free(struct super_block *sb, u32 offset, u32 count) set_page_dirty(page); kunmap(page); page = read_mapping_page(mapping, ++pnr, NULL); + if (IS_ERR(page)) + goto kaboom; pptr = kmap(page); curr = pptr; end = pptr + PAGE_CACHE_BITS / 32; @@ -232,4 +236,11 @@ out: mutex_unlock(&sbi->alloc_mutex); return 0; + +kaboom: + printk(KERN_CRIT "hfsplus: unable to mark blocks free: error %ld\n", + PTR_ERR(page)); + mutex_unlock(&sbi->alloc_mutex); + + return -EIO; }