kybaaz/linux-xiaomi-chiron
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

ext4: fix uniniatilized extent splitting error

Browse source 
Fix bug reported by Dmitry Monakhov caused by lost error code

    Testcase: 

    blksize = 0x1000;
    fd = open(argv[1], O_RDWR|O_CREAT, 0700);
    unsigned long long sz = 0x10000000UL;
    /* allocating big blocks chunk */
    syscall(__NR_fallocate, fd, 0, 0UL, sz)

    /* grab all other available filesystem space */
    tfd = open("tmp", O_RDWR|O_CREAT|O_DIRECT, 0700);
    while( write(tfd, buf, 4096) > 0); /* loop untill ENOSPC */
    fsync(fd); /* just in case */
    while (pos < sz) {
    	/* each seek+ write operation result in splits uninitialized extent
    	in three extents. Splitting may result in new extent allocation
    	which probably will fail because of ENOSPC*/

    	lseek(fd, blksize*2 -1, SEEK_CUR);
    	if ((ret = write(fd, 'a', 1)) != 1)
    		exit(1);
    	pos += blksize * 2;
    }

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This commit is contained in:
Dmitry Monakhov 2008-01-28 23:58:27 -05:00 • committed by Theodore Ts'o
parent ce40733ce9
commit dbf9d7da33
1 changed files with 3 additions and 2 deletions
Download patch file Download diff file Expand all files Collapse all files

5
fs/ext4/extents.c
View file

@ -2373,9 +2373,10 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
ret = ext4_ext_convert_to_initialized(handle, inode,
path, iblock,
max_blocks);
if (ret <= 0)
if (ret <= 0) {
err = ret;
goto out2;
else
} else
allocated = ret;
goto outnew;
}