Re: [PATCH -next v3] netlabel: Fix memory leak in netlbl_mgmt_add_common

From: Paul Moore
Date: Tue Jun 15 2021 - 16:29:21 EST


On Mon, Jun 14, 2021 at 9:43 PM Liu Shixin <liushixin2@xxxxxxxxxx> wrote:
>
> Hulk Robot reported memory leak in netlbl_mgmt_add_common.
> The problem is non-freed map in case of netlbl_domhsh_add() failed.
>
> BUG: memory leak
> unreferenced object 0xffff888100ab7080 (size 96):
> comm "syz-executor537", pid 360, jiffies 4294862456 (age 22.678s)
> hex dump (first 32 bytes):
> 05 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
> fe 00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 ................
> backtrace:
> [<0000000008b40026>] netlbl_mgmt_add_common.isra.0+0xb2a/0x1b40
> [<000000003be10950>] netlbl_mgmt_add+0x271/0x3c0
> [<00000000c70487ed>] genl_family_rcv_msg_doit.isra.0+0x20e/0x320
> [<000000001f2ff614>] genl_rcv_msg+0x2bf/0x4f0
> [<0000000089045792>] netlink_rcv_skb+0x134/0x3d0
> [<0000000020e96fdd>] genl_rcv+0x24/0x40
> [<0000000042810c66>] netlink_unicast+0x4a0/0x6a0
> [<000000002e1659f0>] netlink_sendmsg+0x789/0xc70
> [<000000006e43415f>] sock_sendmsg+0x139/0x170
> [<00000000680a73d7>] ____sys_sendmsg+0x658/0x7d0
> [<0000000065cbb8af>] ___sys_sendmsg+0xf8/0x170
> [<0000000019932b6c>] __sys_sendmsg+0xd3/0x190
> [<00000000643ac172>] do_syscall_64+0x37/0x90
> [<000000009b79d6dc>] entry_SYSCALL_64_after_hwframe+0x44/0xae
>
> Fixes: 63c416887437 ("netlabel: Add network address selectors to the NetLabel/LSM domain mapping")
> Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
> Signed-off-by: Liu Shixin <liushixin2@xxxxxxxxxx>
> ---
> v1->v2: According to Dongliang's and Paul's advices, simplify the code.
> v2->v3: Fix the style error.
>
> net/netlabel/netlabel_mgmt.c | 19 ++++++++++---------
> 1 file changed, 10 insertions(+), 9 deletions(-)

Thanks for the updated patch, it looks good to me. I see it's already
been merged, but for posterity's sake ...

Acked-by: Paul Moore <paul@xxxxxxxxxxxxxx>

--
paul moore
www.paul-moore.com