[PATCH] net: don't forget to free sk_filter
From: Andrey Vagin
Date: Wed Nov 06 2013 - 11:33:13 EST
sk_filter isn't freed if bpf_func is equal to sk_run_filter.
This memory leak was introduced by
commit d45ed4a4e33ae103053c0a53d280014e7101bb5c
Author: Alexei Starovoitov <ast@xxxxxxxxxxxx>
Date: Fri Oct 4 00:14:06 2013 -0700
net: fix unsafe set_memory_rw from softirq
Before this patch sk_filter was freed in sk_filter_release_rcu,
now it is freed in bpf_jit_free.
Here is output of kmemleak:
unreferenced object 0xffff8800b774eab0 (size 128):
comm "systemd", pid 1, jiffies 4294669014 (age 124.062s)
hex dump (first 32 bytes):
00 00 00 00 0b 00 00 00 20 63 7f b7 00 88 ff ff ........ c......
60 d4 55 81 ff ff ff ff 30 d9 55 81 ff ff ff ff `.U.....0.U.....
backtrace:
[<ffffffff816444be>] kmemleak_alloc+0x4e/0xb0
[<ffffffff811845af>] __kmalloc+0xef/0x260
[<ffffffff81534028>] sock_kmalloc+0x38/0x60
[<ffffffff8155d4dd>] sk_attach_filter+0x5d/0x190
[<ffffffff815378a1>] sock_setsockopt+0x991/0x9e0
[<ffffffff81531bd6>] SyS_setsockopt+0xb6/0xd0
[<ffffffff8165f3e9>] system_call_fastpath+0x16/0x1b
[<ffffffffffffffff>] 0xffffffffffffffff
Cc: Alexei Starovoitov <ast@xxxxxxxxxxxx>
Cc: Eric Dumazet <edumazet@xxxxxxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # 3.12
Signed-off-by: Andrey Vagin <avagin@xxxxxxxxxx>
---
arch/x86/net/bpf_jit_comp.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index 516593e..3c55de5 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -788,5 +788,6 @@ void bpf_jit_free(struct sk_filter *fp)
if (fp->bpf_func != sk_run_filter) {
INIT_WORK(&fp->work, bpf_jit_free_deferred);
schedule_work(&fp->work);
- }
+ } else
+ kfree(fp);
}
--
1.8.3.1
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