From: Jan Kara Date: Mon, 24 Oct 2016 03:20:25 +0000 (+1100) Subject: fs: Do to trim high file position bits in iomap_page_mkwrite_actor X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=c663e29f8885269c1608b5aa6057729fa9267b35;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git fs: Do to trim high file position bits in iomap_page_mkwrite_actor iomap_page_mkwrite_actor() calls __block_write_begin_int() with position masked as pos & ~PAGE_MASK which is equivalent to pos & (PAGE_SIZE-1). Thus it masks off high bits of file position. However __block_write_begin_int() expects full file position on input. This does not cause any visible issues because all __block_write_begin_int() really cares about are low file position bits but still it is a bug waiting to happen. Signed-off-by: Jan Kara Reviewed-by: Christoph Hellwig Signed-off-by: Dave Chinner --- diff --git a/fs/iomap.c b/fs/iomap.c index a92204012e2d..a8ee8c33ca78 100644 --- a/fs/iomap.c +++ b/fs/iomap.c @@ -433,8 +433,7 @@ iomap_page_mkwrite_actor(struct inode *inode, loff_t pos, loff_t length, struct page *page = data; int ret; - ret = __block_write_begin_int(page, pos & ~PAGE_MASK, length, - NULL, iomap); + ret = __block_write_begin_int(page, pos, length, NULL, iomap); if (ret) return ret;