Re: [PATCH 1/1] gtp: fix use-after-free and null-ptr-deref in gtp_genl_dump_pdp()
From: kovalev
Date: Wed Feb 14 2024 - 11:51:08 EST
09.02.2024 22:21, Eric Dumazet wrote:
Maybe, but the patch is not good, I think I and Pablo gave feedback on this ?
Please trace __netlink_dump_start() content of control->module
gtp_genl_family.module should be set, and we should get it.
Otherwise, if the bug is in the core, we would need a dozen of 'work
arounds because it is better than nothing'
Thank you.
Thanks.
I tracked the moment when the __netlink_dump_start() function was
called, it turned out that in the gtp_init() initialization function
before registering pernet subsystem (gtp_net_ops), therefore, outdated
data is used, which leads to a crash.
The documentation says that ops structure must be assigned before
registering a generic netlink family [1].
I have fixed and sent a new patch [2].
[1]
https://elixir.bootlin.com/linux/v6.8-rc4/source/net/netlink/genetlink.c#L773
[2]
https://lore.kernel.org/netdev/20240214162733.34214-1-kovalev@xxxxxxxxxxxx/T/#u
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Regards,
Vasiliy Kovalev