linux/net/ipv4/bpfilter, branch master

bpfilter: remove bpfilter

2024-01-04T18:23:10Z

bpfilter was supposed to convert iptables filtering rules into BPF programs on the fly, from the kernel, through a usermode helper. The base code for the UMH was introduced in 2018, and couple of attempts (2, 3) tried to introduce the BPF program generate features but were abandoned. bpfilter now sits in a kernel tree unused and unusable, occasionally causing confusion amongst Linux users (4, 5). As bpfilter is now developed in a dedicated repository on GitHub (6), it was suggested a couple of times this year (LSFMM/BPF 2023, LPC 2023) to remove the deprecated kernel part of the project. This is the purpose of this patch. [1]: https://lore.kernel.org/lkml/20180522022230.2492505-1-ast@kernel.org/ [2]: https://lore.kernel.org/bpf/20210829183608.2297877-1-me@ubique.spb.ru/#t [3]: https://lore.kernel.org/lkml/20221224000402.476079-1-qde@naccy.de/ [4]: https://dxuuu.xyz/bpfilter.html [5]: https://github.com/linuxkit/linuxkit/pull/3904 [6]: https://github.com/facebook/bpfilter Signed-off-by: Quentin Deslandes Link: https://lore.kernel.org/r/20231226130745.465988-1-qde@naccy.de Signed-off-by: Alexei Starovoitov

net: Use umd_cleanup_helper()

2023-05-31T11:06:57Z

bpfilter_umh_cleanup() is the same function as umd_cleanup_helper(). Drop the redundant function. Signed-off-by: Jarkko Sakkinen Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20230526112104.1044686-1-jarkko@kernel.org

net: Revert "net: optimize the sockptr_t for unified kernel/user address spaces"

2020-08-10T19:06:44Z

This reverts commits 6d04fe15f78acdf8e32329e208552e226f7a8ae6 and a31edb2059ed4e498f9aa8230c734b59d0ad797a. It turns out the idea to share a single pointer for both kernel and user space address causes various kinds of problems. So use the slightly less optimal version that uses an extra bit, but which is guaranteed to be safe everywhere. Fixes: 6d04fe15f78a ("net: optimize the sockptr_t for unified kernel/user address spaces") Reported-by: Eric Dumazet Reported-by: John Stultz Signed-off-by: Christoph Hellwig Signed-off-by: David S. Miller

net: improve the user pointer check in init_user_sockptr

2020-07-28T20:43:40Z

Make sure not just the pointer itself but the whole range lies in the user address space. For that pass the length and then use the access_ok helper to do the check. Fixes: 6d04fe15f78a ("net: optimize the sockptr_t for unified kernel/user address spaces") Reported-by: David Laight Signed-off-by: Christoph Hellwig Signed-off-by: David S. Miller

net: optimize the sockptr_t for unified kernel/user address spaces

2020-07-24T22:41:54Z

For architectures like x86 and arm64 we don't need the separate bit to indicate that a pointer is a kernel pointer as the address spaces are unified. That way the sockptr_t can be reduced to a union of two pointers, which leads to nicer calling conventions. The only caveat is that we need to check that users don't pass in kernel address and thus gain access to kernel memory. Thus the USER_SOCKPTR helper is replaced with a init_user_sockptr function that does this check and returns an error if it fails. Signed-off-by: Christoph Hellwig Signed-off-by: David S. Miller

bpfilter: switch bpfilter_ip_set_sockopt to sockptr_t

2020-07-24T22:41:54Z

This is mostly to prepare for cleaning up the callers, as bpfilter by design can't handle kernel pointers. Signed-off-by: Christoph Hellwig Signed-off-by: David S. Miller

bpfilter: Take advantage of the facilities of struct pid

2020-07-07T16:58:57Z

Instead of relying on the exit_umh cleanup callback use the fact a struct pid can be tested to see if a process still exists, and that struct pid has a wait queue that notifies when the process dies. v1: https://lkml.kernel.org/r/87h7uydlu9.fsf_-_@x220.int.ebiederm.org v2: https://lkml.kernel.org/r/874kqt4owu.fsf_-_@x220.int.ebiederm.org Link: https://lkml.kernel.org/r/20200702164140.4468-14-ebiederm@xmission.com Reviewed-by: Greg Kroah-Hartman Acked-by: Alexei Starovoitov Tested-by: Alexei Starovoitov Signed-off-by: "Eric W. Biederman"

umd: Track user space drivers with struct pid

2020-07-04T14:35:56Z

Use struct pid instead of user space pid values that are prone to wrap araound. In addition track the entire thread group instead of just the first thread that is started by exec. There are no multi-threaded user mode drivers today but there is nothing preclucing user drivers from being multi-threaded, so it is just a good idea to track the entire process. Take a reference count on the tgid's in question to make it possible to remove exit_umh in a future change. As a struct pid is available directly use kill_pid_info. The prior process signalling code was iffy in using a userspace pid known to be in the initial pid namespace and then looking up it's task in whatever the current pid namespace is. It worked only because kernel threads always run in the initial pid namespace. As the tgid is now refcounted verify the tgid is NULL at the start of fork_usermode_driver to avoid the possibility of silent pid leaks. v1: https://lkml.kernel.org/r/87mu4qdlv2.fsf_-_@x220.int.ebiederm.org v2: https://lkml.kernel.org/r/a70l4oy8.fsf_-_@x220.int.ebiederm.org Link: https://lkml.kernel.org/r/20200702164140.4468-12-ebiederm@xmission.com Reviewed-by: Greg Kroah-Hartman Acked-by: Alexei Starovoitov Tested-by: Alexei Starovoitov Signed-off-by: "Eric W. Biederman"

umd: Rename umd_info.cmdline umd_info.driver_name

2020-07-04T14:35:13Z

The only thing supplied in the cmdline today is the driver name so rename the field to clarify the code. As this value is always supplied stop trying to handle the case of a NULL cmdline. Additionally since we now have a name we can count on use the driver_name any place where the code is looking for a name of the binary. v1: https://lkml.kernel.org/r/87imfef0k3.fsf_-_@x220.int.ebiederm.org v2: https://lkml.kernel.org/r/87366d63os.fsf_-_@x220.int.ebiederm.org Link: https://lkml.kernel.org/r/20200702164140.4468-7-ebiederm@xmission.com Reviewed-by: Greg Kroah-Hartman Acked-by: Alexei Starovoitov Tested-by: Alexei Starovoitov Signed-off-by: "Eric W. Biederman"

umd: For clarity rename umh_info umd_info

2020-07-04T14:34:39Z

This structure is only used for user mode drivers so change the prefix from umh to umd to make that clear. v1: https://lkml.kernel.org/r/87o8p6f0kw.fsf_-_@x220.int.ebiederm.org v2: https://lkml.kernel.org/r/878sg563po.fsf_-_@x220.int.ebiederm.org Link: https://lkml.kernel.org/r/20200702164140.4468-6-ebiederm@xmission.com Reviewed-by: Greg Kroah-Hartman Acked-by: Alexei Starovoitov Tested-by: Alexei Starovoitov Signed-off-by: "Eric W. Biederman"