Re: gdb log of crashed "btrfs-image -s"

[Christoph Groth <christoph@grothesque.org>]

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Goldwyn Rodrigues wrote:
> Thanks Christoph for the backtrace. I am unable to reproduce it, 
> but looking at your backtrace, I found a bug. Would you be able 
> to give it a try and check if it fixes the problem?

I applied your patch to v4.9, and compiled the static binaries. 
Unfortunately, it still segfaults. (Perhaps your fix is correct, 
and there's a second problem?)  I attach a new backtrace.  Do let 
me know if I can help in another way.


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root@xubuntu:~# gdb /mnt/btrfs-image.static 
GNU gdb (Ubuntu 7.11-0ubuntu1) 7.11
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Reading symbols from /mnt/btrfs-image.static...done.
(gdb) run -s -c3 /dev/sda2 /mnt/mim.bim
Starting program: /mnt/btrfs-image.static -s -c3 /dev/sda2 /mnt/mim.bim
[New LWP 2334]
[New LWP 2335]
[New LWP 2336]
[New LWP 2337]
*** Error in `/mnt/btrfs-image.static': double free or corruption (out): 0x0000000000772f70 ***
======= Backtrace: =========
[0x45fba7]
[0x465452]
[0x465c2e]
[0x402694]
[0x402dce]
[0x403201]
[0x405102]
[0x405786]
[0x44cb83]
[0x44ce0e]
[0x400b2a]
======= Memory map: ========
00400000-00521000 r-xp 00000000 08:21 689                                /mnt/btrfs-image.static
00721000-00728000 rw-p 00121000 08:21 689                                /mnt/btrfs-image.static
00728000-007e4000 rw-p 00000000 00:00 0                                  [heap]
7fffe0000000-7fffe017e000 rw-p 00000000 00:00 0 
7fffe017e000-7fffe4000000 ---p 00000000 00:00 0 
7fffe4000000-7fffe4025000 rw-p 00000000 00:00 0 
7fffe4025000-7fffe8000000 ---p 00000000 00:00 0 
7fffe8000000-7fffe81a6000 rw-p 00000000 00:00 0 
7fffe81a6000-7fffec000000 ---p 00000000 00:00 0 
7fffec000000-7fffec17c000 rw-p 00000000 00:00 0 
7fffec17c000-7ffff0000000 ---p 00000000 00:00 0 
7ffff0000000-7ffff019a000 rw-p 00000000 00:00 0 
7ffff019a000-7ffff4000000 ---p 00000000 00:00 0 
7ffff5ff6000-7ffff5ff7000 rw-p 00000000 00:00 0 
7ffff5ff7000-7ffff5ff8000 ---p 00000000 00:00 0 
7ffff5ff8000-7ffff67f8000 rw-p 00000000 00:00 0 
7ffff67f8000-7ffff67f9000 ---p 00000000 00:00 0 
7ffff67f9000-7ffff6ff9000 rw-p 00000000 00:00 0 
7ffff6ff9000-7ffff6ffa000 ---p 00000000 00:00 0 
7ffff6ffa000-7ffff77fa000 rw-p 00000000 00:00 0 
7ffff77fa000-7ffff77fb000 ---p 00000000 00:00 0 
7ffff77fb000-7ffff7ffb000 rw-p 00000000 00:00 0 
7ffff7ffb000-7ffff7ffd000 r--p 00000000 00:00 0                          [vvar]
7ffff7ffd000-7ffff7fff000 r-xp 00000000 00:00 0                          [vdso]
7ffffffde000-7ffffffff000 rw-p 00000000 00:00 0                          [stack]
ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0                  [vsyscall]

Thread 1 "btrfs-image.sta" received signal SIGABRT, Aborted.
0x00000000004521ee in raise ()
(gdb) bt
#0  0x00000000004521ee in raise ()
#1  0x00000000004523ba in abort ()
#2  0x000000000045fbac in __libc_message ()
#3  0x0000000000465452 in malloc_printerr ()
#4  0x0000000000465c2e in _int_free ()
#5  0x0000000000402694 in sanitize_inode_ref (md=md@entry=0x7fffffffde00, eb=eb@entry=0x771ee0, slot=slot@entry=16, ext=ext@entry=0) at image/main.c:522
#6  0x0000000000402dce in sanitize_name (slot=16, key=<synthetic pointer>, src=0x764cf0, dst=0x76bed0 "4\246", <incomplete sequence \367\261>, md=0x7fffffffde00)
    at image/main.c:561
#7  zero_items (src=0x764cf0, dst=0x76bed0 "4\246", <incomplete sequence \367\261>, md=<optimized out>) at image/main.c:602
#8  copy_buffer (src=0x764cf0, dst=0x76bed0 "4\246", <incomplete sequence \367\261>, md=<optimized out>) at image/main.c:645
#9  flush_pending (md=md@entry=0x7fffffffde00, done=done@entry=0) at image/main.c:983
#10 0x0000000000403201 in add_extent (start=start@entry=192589824, size=size@entry=4096, md=md@entry=0x7fffffffde00, data=data@entry=0) at image/main.c:1025
#11 0x0000000000405102 in copy_from_extent_tree (path=0x7fffffffe3d0, metadump=0x7fffffffde00) at image/main.c:1280
#12 create_metadump (input=input@entry=0x7fffffffe87f "/dev/sda2", out=out@entry=0x731be0, num_threads=num_threads@entry=4, compress_level=compress_level@entry=3, 
    sanitize=sanitize@entry=1, walk_trees=walk_trees@entry=0) at image/main.c:1370
#13 0x0000000000405786 in main (argc=<optimized out>, argv=0x7fffffffe618) at image/main.c:2855


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