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  1. 25 7月, 2020 3 次提交
  3. 20 7月, 2020 4 次提交
  5. 14 7月, 2020 1 次提交
  7. 05 7月, 2020 1 次提交
  9. 30 5月, 2020 1 次提交
  11. 28 5月, 2020 1 次提交
  13. 19 5月, 2020 2 次提交
  15. 12 5月, 2020 1 次提交
    • C
      net: cleanly handle kernel vs user buffers for ->msg_control · 1f466e1f
      由 Christoph Hellwig 提交于 
      The msg_control field in struct msghdr can either contain a user
pointer when used with the recvmsg system call, or a kernel pointer
when used with sendmsg.  To complicate things further kernel_recvmsg
can stuff a kernel pointer in and then use set_fs to make the uaccess
helpers accept it.

Replace it with a union of a kernel pointer msg_control field, and
a user pointer msg_control_user one, and allow kernel_recvmsg operate
on a proper kernel pointer using a bitfield to override the normal
choice of a user pointer for recvmsg.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      1f466e1f
  17. 20 3月, 2020 1 次提交
  19. 10 3月, 2020 1 次提交
  21. 09 1月, 2020 1 次提交
  23. 13 12月, 2019 1 次提交
  25. 11 12月, 2019 1 次提交
  27. 07 12月, 2019 1 次提交
  29. 03 12月, 2019 2 次提交
  31. 27 11月, 2019 2 次提交
  33. 26 11月, 2019 2 次提交
    • J
      net: add __sys_connect_file() helper · bd3ded31
      由 Jens Axboe 提交于 
      This is identical to __sys_connect(), except it takes a struct file
instead of an fd, and it also allows passing in extra file->f_flags
flags. The latter is done to support masking in O_NONBLOCK without
manipulating the original file flags.

No functional changes in this patch.

Cc: netdev@vger.kernel.org
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      bd3ded31
    • L
      vfs: mark pipes and sockets as stream-like file descriptors · d8e464ec
      由 Linus Torvalds 提交于 
      In commit 3975b097 ("convert stream-like files -> stream_open, even
if they use noop_llseek") Kirill used a coccinelle script to change
"nonseekable_open()" to "stream_open()", which changed the trivial cases
of stream-like file descriptors to the new model with FMODE_STREAM.

However, the two big cases - sockets and pipes - don't actually have
that trivial pattern at all, and were thus never converted to
FMODE_STREAM even though it makes lots of sense to do so.

That's particularly true when looking forward to the next change:
getting rid of FMODE_ATOMIC_POS entirely, and just using FMODE_STREAM to
decide whether f_pos updates are needed or not.  And if they are, we'll
always do them atomically.

This came up because KCSAN (correctly) noted that the non-locked f_pos
updates are data races: they are clearly benign for the case where we
don't care, but it would be good to just not have that issue exist at
all.

Note that the reason we used FMODE_ATOMIC_POS originally is that only
doing it for the minimal required case is "safer" in that it's possible
that the f_pos locking can cause unnecessary serialization across the
whole write() call.  And in the worst case, that kind of serialization
can cause deadlock issues: think writers that need readers to empty the
state using the same file descriptor.

[ Note that the locking is per-file descriptor - because it protects
  "f_pos", which is obviously per-file descriptor - so it only affects
  cases where you literally use the same file descriptor to both read
  and write.

  So a regular pipe that has separate reading and writing file
  descriptors doesn't really have this situation even though it's the
  obvious case of "reader empties what a bit writer concurrently fills"

  But we want to make pipes as being stream-line anyway, because we
  don't want the unnecessary overhead of locking, and because a named
  pipe can be (ab-)used by reading and writing to the same file
  descriptor. ]

There are likely a lot of other cases that might want FMODE_STREAM, and
looking for ".llseek = no_llseek" users and other cases that don't have
an lseek file operation at all and making them use "stream_open()" might
be a good idea.  But pipes and sockets are likely to be the two main
cases.

Cc: Kirill Smelkov <kirr@nexedi.com>
Cc: Eic Dumazet <edumazet@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Marco Elver <elver@google.com>
Cc: Andrea Parri <parri.andrea@gmail.com>
Cc: Paul McKenney <paulmck@kernel.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      d8e464ec
  35. 15 11月, 2019 2 次提交
  37. 30 10月, 2019 1 次提交
  39. 23 10月, 2019 2 次提交
  41. 10 7月, 2019 2 次提交
  43. 09 7月, 2019 2 次提交
    • A
      coallocate socket_wq with socket itself · 333f7909
      由 Al Viro 提交于 
      socket->wq is assign-once, set when we are initializing both
struct socket it's in and struct socket_wq it points to.  As the
matter of fact, the only reason for separate allocation was the
ability to RCU-delay freeing of socket_wq.  RCU-delaying the
freeing of socket itself gets rid of that need, so we can just
fold struct socket_wq into the end of struct socket and simplify
the life both for sock_alloc_inode() (one allocation instead of
two) and for tun/tap oddballs, where we used to embed struct socket
and struct socket_wq into the same structure (now - embedding just
the struct socket).

Note that reference to struct socket_wq in struct sock does remain
a reference - that's unchanged.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      333f7909
    • A
      sockfs: switch to ->free_inode() · 6d7855c5
      由 Al Viro 提交于 
      we do have an RCU-delayed part there already (freeing the wq),
so it's not like the pipe situation; moreover, it might be
worth considering coallocating wq with the rest of struct sock_alloc.
->sk_wq in struct sock would remain a pointer as it is, but
the object it normally points to would be coallocated with
struct socket...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      6d7855c5
  45. 04 7月, 2019 1 次提交
  47. 28 6月, 2019 1 次提交
    • S
      bpf: implement getsockopt and setsockopt hooks · 0d01da6a
      由 Stanislav Fomichev 提交于 
      Implement new BPF_PROG_TYPE_CGROUP_SOCKOPT program type and
BPF_CGROUP_{G,S}ETSOCKOPT cgroup hooks.

BPF_CGROUP_SETSOCKOPT can modify user setsockopt arguments before
passing them down to the kernel or bypass kernel completely.
BPF_CGROUP_GETSOCKOPT can can inspect/modify getsockopt arguments that
kernel returns.
Both hooks reuse existing PTR_TO_PACKET{,_END} infrastructure.

The buffer memory is pre-allocated (because I don't think there is
a precedent for working with __user memory from bpf). This might be
slow to do for each {s,g}etsockopt call, that's why I've added
__cgroup_bpf_prog_array_is_empty that exits early if there is nothing
attached to a cgroup. Note, however, that there is a race between
__cgroup_bpf_prog_array_is_empty and BPF_PROG_RUN_ARRAY where cgroup
program layout might have changed; this should not be a problem
because in general there is a race between multiple calls to
{s,g}etsocktop and user adding/removing bpf progs from a cgroup.

The return code of the BPF program is handled as follows:
* 0: EPERM
* 1: success, continue with next BPF program in the cgroup chain

v9:
* allow overwriting setsockopt arguments (Alexei Starovoitov):
  * use set_fs (same as kernel_setsockopt)
  * buffer is always kzalloc'd (no small on-stack buffer)

v8:
* use s32 for optlen (Andrii Nakryiko)

v7:
* return only 0 or 1 (Alexei Starovoitov)
* always run all progs (Alexei Starovoitov)
* use optval=0 as kernel bypass in setsockopt (Alexei Starovoitov)
  (decided to use optval=-1 instead, optval=0 might be a valid input)
* call getsockopt hook after kernel handlers (Alexei Starovoitov)

v6:
* rework cgroup chaining; stop as soon as bpf program returns
  0 or 2; see patch with the documentation for the details
* drop Andrii's and Martin's Acked-by (not sure they are comfortable
  with the new state of things)

v5:
* skip copy_to_user() and put_user() when ret == 0 (Martin Lau)

v4:
* don't export bpf_sk_fullsock helper (Martin Lau)
* size != sizeof(__u64) for uapi pointers (Martin Lau)
* offsetof instead of bpf_ctx_range when checking ctx access (Martin Lau)

v3:
* typos in BPF_PROG_CGROUP_SOCKOPT_RUN_ARRAY comments (Andrii Nakryiko)
* reverse christmas tree in BPF_PROG_CGROUP_SOCKOPT_RUN_ARRAY (Andrii
  Nakryiko)
* use __bpf_md_ptr instead of __u32 for optval{,_end} (Martin Lau)
* use BPF_FIELD_SIZEOF() for consistency (Martin Lau)
* new CG_SOCKOPT_ACCESS macro to wrap repeated parts

v2:
* moved bpf_sockopt_kern fields around to remove a hole (Martin Lau)
* aligned bpf_sockopt_kern->buf to 8 bytes (Martin Lau)
* bpf_prog_array_is_empty instead of bpf_prog_array_length (Martin Lau)
* added [0,2] return code check to verifier (Martin Lau)
* dropped unused buf[64] from the stack (Martin Lau)
* use PTR_TO_SOCKET for bpf_sockopt->sk (Martin Lau)
* dropped bpf_target_off from ctx rewrites (Martin Lau)
* use return code for kernel bypass (Martin Lau & Andrii Nakryiko)

Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Martin Lau <kafai@fb.com>
Signed-off-by: NStanislav Fomichev <sdf@google.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
      0d01da6a
  49. 06 6月, 2019 1 次提交
  51. 01 6月, 2019 1 次提交
  53. 31 5月, 2019 1 次提交