Re: [PATCH -next] scsi: scsi_dh_alua: fix memleak for 'qdata' in alua_activate()

[Benjamin Block]

On Wed, Mar 15, 2023 at 02:21:54PM +0800, Yu Kuai wrote:
> From: Yu Kuai <yukuai3@xxxxxxxxxx>
> 
> If alua_rtpg_queue() failed from alua_activate(), then 'qdata' is not
> freed, which will cause following memleak:
> 
> unreferenced object 0xffff88810b2c6980 (size 32):
>   comm "kworker/u16:2", pid 635322, jiffies 4355801099 (age 1216426.076s)
>   hex dump (first 32 bytes):
>     00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
>     40 39 24 c1 ff ff ff ff 00 f8 ea 0a 81 88 ff ff  @9$.............
>   backtrace:
>     [<0000000098f3a26d>] alua_activate+0xb0/0x320
>     [<000000003b529641>] scsi_dh_activate+0xb2/0x140
>     [<000000007b296db3>] activate_path_work+0xc6/0xe0 [dm_multipath]
>     [<000000007adc9ace>] process_one_work+0x3c5/0x730
>     [<00000000c457a985>] worker_thread+0x93/0x650
>     [<00000000cb80e628>] kthread+0x1ba/0x210
>     [<00000000a1e61077>] ret_from_fork+0x22/0x30
> 
> Fix the problem by freeing 'qdata' in error path.
> 
> Fixes: 625fe857e4fa ("scsi: scsi_dh_alua: Check scsi_device_get() return value")
> Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
> ---
>  drivers/scsi/device_handler/scsi_dh_alua.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 

Looks good to me.


Reviewed-by: Benjamin Block <bblock@xxxxxxxxxxxxx>

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