Qingfang Deng 631fc8ab5b ppp: fix memory leak in pad_compress_skb ...

[ Upstream commit 4844123fe0 ]

If alloc_skb() fails in pad_compress_skb(), it returns NULL without
releasing the old skb. The caller does:

    skb = pad_compress_skb(ppp, skb);
    if (!skb)
        goto drop;

drop:
    kfree_skb(skb);

When pad_compress_skb() returns NULL, the reference to the old skb is
lost and kfree_skb(skb) ends up doing nothing, leading to a memory leak.

Align pad_compress_skb() semantics with realloc(): only free the old
skb if allocation and compression succeed.  At the call site, use the
new_skb variable so the original skb is not lost when pad_compress_skb()
fails.

Fixes: b3f9b92a6e ("[PPP]: add PPP MPPE encryption module")
Signed-off-by: Qingfang Deng <dqfext@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Yue Haibing <yuehaibing@huawei.com>
Link: https://patch.msgid.link/20250903100726.269839-1-dqfext@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

2025-09-09 18:58:14 +02:00

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bsd_comp.c

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Kconfig

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Makefile

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ppp_async.c

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ppp_deflate.c

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ppp_generic.c

ppp: fix memory leak in pad_compress_skb

2025-09-09 18:58:14 +02:00

ppp_mppe.c

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ppp_mppe.h

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ppp_synctty.c

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pppoe.c

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pppox.c

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pptp.c

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