1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
|
URL: https://bugzilla.kernel.org/show_bug.cgi?id=97041
Lukas Lueg 2015-04-21 21:53:14 UTC
The btrfs-image attached to this bug causes the userland tools v3.19.1 to
crash with a SIGFPE. The problem is that map->sub_stripes in
__btrfs_map_block() is allowed to be 0 before entering a division.
The userland tool crashes. The kernel reports a "divide error: 0000 ..."
with a traceback from __btrfs_map_block()
(gdb) run check btrfs_fukked_sigfpe_volumes:1404.bin
Starting program: /usr/sbin/btrfs check btrfs_fukked_sigfpe_volumes:1404.bin
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
Program received signal SIGFPE, Arithmetic exception.
0x000000000044d7b6 in __btrfs_map_block (map_tree=map_tree@entry=0x88c170,
rw=rw@entry=0, logical=<optimized out>, length=length@entry=0x7fffffffd8f0,
type=type@entry=0x0, multi_ret=multi_ret@entry=0x7fffffffd8e8, mirror_num=0,
raid_map_ret=0x0) at volumes.c:1404
1404 int factor = map->num_stripes / map->sub_stripes;
(gdb) bt
#0 0x000000000044d7b6 in __btrfs_map_block (map_tree=map_tree@entry=0x88c170,
rw=rw@entry=0, logical=<optimized out>, length=length@entry=0x7fffffffd8f0,
type=type@entry=0x0, multi_ret=multi_ret@entry=0x7fffffffd8e8, mirror_num=0,
raid_map_ret=0x0) at volumes.c:1404
#1 0x000000000044db45 in btrfs_map_block (map_tree=map_tree@entry=0x88c170,
rw=rw@entry=0, logical=<optimized out>, length=length@entry=0x7fffffffd8f0,
multi_ret=multi_ret@entry=0x7fffffffd8e8, mirror_num=mirror_num@entry=0,
raid_map_ret=0x0) at volumes.c:1291
#2 0x000000000043b22d in read_whole_eb (info=0x88c010, eb=eb@entry=0x88f400,
mirror=mirror@entry=0) at disk-io.c:232
#3 0x000000000043caa2 in read_tree_block (root=root@entry=0x88c710,
bytenr=<optimized out>, blocksize=<optimized out>, parent_transid=5)
at disk-io.c:295
#4 0x000000000043d5df in btrfs_setup_chunk_tree_and_device_map (
fs_info=fs_info@entry=0x88c010) at disk-io.c:1106
#5 0x000000000043d7d1 in __open_ctree_fd (fp=fp@entry=3,
path=path@entry=0x7fffffffe1fa "btrfs_fukked_sigfpe_volumes:1404.bin",
sb_bytenr=65536, sb_bytenr@entry=0, root_tree_bytenr=root_tree_bytenr@entry=0,
flags=flags@entry=OPEN_CTREE_EXCLUSIVE) at disk-io.c:1190
#6 0x000000000043d965 in open_ctree_fs_info (
filename=0x7fffffffe1fa "btrfs_fukked_sigfpe_volumes:1404.bin",
sb_bytenr=sb_bytenr@entry=0, root_tree_bytenr=root_tree_bytenr@entry=0,
flags=flags@entry=OPEN_CTREE_EXCLUSIVE) at disk-io.c:1231
#7 0x0000000000427bf5 in cmd_check (argc=1, argv=0x7fffffffde90) at cmds-check.c:9326
#8 0x000000000040e5a2 in main (argc=2, argv=0x7fffffffde90) at btrfs.c:245
(gdb) p map->sub_stripes
$1 = 0
|
