[bug report] kmemleak observed during blktests nbd/009

[bug report] kmemleak observed during blktests nbd/009

[Yi Zhang]

Hi

I found below kmemleak during blktests nbd/009 on 6.8.0-rc3+, please
help check it and let me know if you need any info/testing for it,
thanks.

[17763.119952] kmemleak: 12 new suspected memory leaks (see
/sys/kernel/debug/kmemleak)

# ./check zbd/009
zbd/009 (test gap zone support with BTRFS)                   [passed]
    runtime  18.716s  ...  18.763s
# btrfs --version
btrfs-progs v6.7

unreferenced object 0xffff8881511c53b0 (size 192):
  comm "mount", pid 52857, jiffies 4311808306
  hex dump (first 32 bytes):
    b0 53 1c 51 81 88 ff ff 00 40 1c 51 81 88 ff ff  .S.Q.....@.Q....
    00 00 00 00 00 00 00 00 02 00 00 00 01 00 00 00  ................
  backtrace (crc dcabc4f4):
    [<0000000097edeb04>] __kmalloc+0x3e7/0x520
    [<00000000288772fe>] btrfs_alloc_chunk_map.constprop.0+0x20/0xa0
    [<0000000031efcd2f>] read_one_chunk+0x284/0xb80
    [<00000000e2b85033>] btrfs_read_sys_array+0x24c/0x3d0
    [<0000000003714897>] open_ctree+0x1b0b/0x4be0
    [<000000001f5e8ac7>] btrfs_get_tree+0x101f/0x19d0
    [<0000000088ba3feb>] vfs_get_tree+0x8d/0x350
    [<000000001f72c23c>] fc_mount+0x13/0x90
    [<00000000c75588a6>] btrfs_get_tree+0x91d/0x19d0
    [<0000000088ba3feb>] vfs_get_tree+0x8d/0x350
    [<00000000706df581>] vfs_cmd_create+0xe1/0x290
    [<000000004d6ccd48>] __do_sys_fsconfig+0x607/0xa90
    [<00000000c1740ec7>] do_syscall_64+0x9e/0x190
    [<0000000014a2c6d4>] entry_SYSCALL_64_after_hwframe+0x6e/0x76

(gdb) l *(btrfs_create_chunk+0x11b2)
0xffffffff822bd922 is in btrfs_create_chunk (fs/btrfs/volumes.c:5544).
5539 u64 type = ctl->type;
5540 int ret;
5541 int i;
5542 int j;
5543
5544 map = btrfs_alloc_chunk_map(ctl->num_stripes, GFP_NOFS);
5545 if (!map)



-- 
Best Regards,
  Yi Zhang

Re: [bug report] kmemleak observed during blktests nbd/009

[David Sterba]

On Wed, Feb 14, 2024 at 04:14:32PM +0800, Yi Zhang wrote:
> Hi
> 
> I found below kmemleak during blktests nbd/009 on 6.8.0-rc3+, please
> help check it and let me know if you need any info/testing for it,
> thanks.
> 
> [17763.119952] kmemleak: 12 new suspected memory leaks (see
> /sys/kernel/debug/kmemleak)
> 
> # ./check zbd/009
> zbd/009 (test gap zone support with BTRFS)                   [passed]
>     runtime  18.716s  ...  18.763s
> # btrfs --version
> btrfs-progs v6.7
> 
> unreferenced object 0xffff8881511c53b0 (size 192):
>   comm "mount", pid 52857, jiffies 4311808306
>   hex dump (first 32 bytes):
>     b0 53 1c 51 81 88 ff ff 00 40 1c 51 81 88 ff ff  .S.Q.....@.Q....
>     00 00 00 00 00 00 00 00 02 00 00 00 01 00 00 00  ................
>   backtrace (crc dcabc4f4):
>     [<0000000097edeb04>] __kmalloc+0x3e7/0x520
>     [<00000000288772fe>] btrfs_alloc_chunk_map.constprop.0+0x20/0xa0
>     [<0000000031efcd2f>] read_one_chunk+0x284/0xb80
>     [<00000000e2b85033>] btrfs_read_sys_array+0x24c/0x3d0
>     [<0000000003714897>] open_ctree+0x1b0b/0x4be0
>     [<000000001f5e8ac7>] btrfs_get_tree+0x101f/0x19d0
>     [<0000000088ba3feb>] vfs_get_tree+0x8d/0x350
>     [<000000001f72c23c>] fc_mount+0x13/0x90
>     [<00000000c75588a6>] btrfs_get_tree+0x91d/0x19d0
>     [<0000000088ba3feb>] vfs_get_tree+0x8d/0x350
>     [<00000000706df581>] vfs_cmd_create+0xe1/0x290
>     [<000000004d6ccd48>] __do_sys_fsconfig+0x607/0xa90
>     [<00000000c1740ec7>] do_syscall_64+0x9e/0x190
>     [<0000000014a2c6d4>] entry_SYSCALL_64_after_hwframe+0x6e/0x76

Thanks for the report, fixed by
https://lore.kernel.org/linux-btrfs/0bdc61c9216d238eaa4abb6edfb1c5d9c8e86c52.1707775003.git.fdmanana@suse.com/