Messages in this thread | | | Date | Mon, 1 Aug 2016 11:57:50 -0700 | From | Davidlohr Bueso <> | Subject | Re: [PATCH V2 linux-next] ipc/msg.c: fix memory leak in do_msgsnd() |
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On Mon, 01 Aug 2016, Fabian Frederick wrote:
>Commit 53dad6d3a8e5 >("ipc: fix race with LSMs") updated ipc_rcu_putref() to receive >rcu freeing function but used generic ipc_rcu_free() instead >of msg_rcu_free() which does security cleaning. > >Running LTP msgsnd06 with kmemleak gives the following: > >cat /sys/kernel/debug/kmemleak > >unreferenced object 0xffff88003c0a11f8 (size 8): > comm "msgsnd06", pid 1645, jiffies 4294672526 (age 6.549s) > hex dump (first 8 bytes): > 1b 00 00 00 01 00 00 00 ........ > backtrace: > [<ffffffff818e2c43>] kmemleak_alloc+0x23/0x40 > [<ffffffff81177f31>] kmem_cache_alloc_trace+0xe1/0x180 > [<ffffffff812d42af>] selinux_msg_queue_alloc_security+0x3f/0xd0 > [<ffffffff812cc6be>] security_msg_queue_alloc+0x2e/0x40 > [<ffffffff812b94ee>] newque+0x4e/0x150 > [<ffffffff812b8cb9>] ipcget+0x159/0x1b0 > [<ffffffff812b98d9>] SyS_msgget+0x39/0x40 > [<ffffffff818e7bdb>] entry_SYSCALL_64_fastpath+0x13/0x8f > [<ffffffffffffffff>] 0xffffffffffffffff > >Signed-off-by: Fabian Frederick <fabf@skynet.be> >--- >V2: Update description with original commit and cc stable >(Suggested by Manfred Spraul)
Ideally we would have the fix for sem.c in the same patch, under, ie:
"sysv, ipc: fix security-layer leaking"
Just like with shm and msg, the only caller of ipc_rcu_free() should be a failed security allocation in newary().
Thanks, Davidlohr
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