From 2e023174a88dd14eab30fae3a1f6c97f37eb3bb8 Mon Sep 17 00:00:00 2001 From: Chao Yu Date: Mon, 9 Feb 2015 11:23:58 +0800 Subject: f2fs: avoid data offset overflow when lseeking huge file xfstest generic/285 complains our issue in lseeking huge file. Here is the detail output of generic/285: "./check -f2fs tests/generic/285 Ran: generic/285 Failures: generic/285 Failed 1 of 1 tests 10. Test a huge file for offset overflow 10.01 SEEK_HOLE expected 65536 or 8589934592, got 65536. succ 10.02 SEEK_HOLE expected 65536 or 8589934592, got 65536. succ 10.03 SEEK_DATA expected 0 or 0, got 0. succ 10.04 SEEK_DATA expected 1 or 1, got 1. succ 10.05 SEEK_HOLE expected 8589934592 or 8589934592, got 0. FAIL 10.06 SEEK_DATA expected 8589869056 or 8589869056, got 8589869056. succ 10.07 SEEK_DATA expected 8589869057 or 8589869057, got 8589869057. succ 10.08 SEEK_DATA expected 8589869056 or 8589869056, got 4294901760. FAIL" The reason of this issue is: We will calculate current offset through left shifting page-offset with PAGE_CACHE_SHIFT bits, but our page-offset is a type of unsigned long, its size is 4 bytes in 32-bits machine. So if our page-offset is bigger than (1 << 32 / pagesize - 1), result of left shifting will overflow. Let's fix this issue by casting type of page-offset to type of current offset: loff_t. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/file.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/f2fs') diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index ec17d05d6553..7188a2ac64b5 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -357,7 +357,7 @@ static loff_t f2fs_seek_block(struct file *file, loff_t offset, int whence) /* find data/hole in dnode block */ for (; dn.ofs_in_node < end_offset; dn.ofs_in_node++, pgofs++, - data_ofs = pgofs << PAGE_CACHE_SHIFT) { + data_ofs = (loff_t)pgofs << PAGE_CACHE_SHIFT) { block_t blkaddr; blkaddr = datablock_addr(dn.node_page, dn.ofs_in_node); -- cgit v1.2.3