file: stop exposing receive_fd_user()

Not every subsystem needs to have their own specialized helper.
Just us the __receive_fd() helper.

Link: https://lore.kernel.org/r/20231130-vfs-files-fixes-v1-

file: stop exposing receive_fd_user()

Not every subsystem needs to have their own specialized helper.
Just us the __receive_fd() helper.

Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Jan Kara <[email protected]>
Reviewed-by: Jens Axboe <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

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net/compat: Update msg_control_is_user when setting a kernel pointer

cmsghdr_from_user_compat_to_kern() is an unusual case w.r.t. how
the kmsg->msg_control* fields are used. The input struct msghdr

net/compat: Update msg_control_is_user when setting a kernel pointer

cmsghdr_from_user_compat_to_kern() is an unusual case w.r.t. how
the kmsg->msg_control* fields are used. The input struct msghdr
holds a pointer to a user buffer, i.e. ksmg->msg_control_user is
active. However, upon success, a kernel pointer is stored in
kmsg->msg_control. kmsg->msg_control_is_user should therefore be
updated accordingly.

Cc: Christoph Hellwig <[email protected]>
Cc: Eric Dumazet <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Jakub Kicinski <[email protected]>
Signed-off-by: Kevin Brodsky <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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net: Ensure ->msg_control_user is used for user buffers

Since commit 1f466e1f15cf ("net: cleanly handle kernel vs user
buffers for ->msg_control"), pointers to user buffers should be
stored in struc

net: Ensure ->msg_control_user is used for user buffers

Since commit 1f466e1f15cf ("net: cleanly handle kernel vs user
buffers for ->msg_control"), pointers to user buffers should be
stored in struct msghdr::msg_control_user, instead of the
msg_control field. Most users of msg_control have already been
converted (where user buffers are involved), but not all of them.

This patch attempts to address the remaining cases. An exception is
made for null checks, as it should be safe to use msg_control
unconditionally for that purpose.

Cc: Christoph Hellwig <[email protected]>
Cc: Eric Dumazet <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Jakub Kicinski <[email protected]>
Signed-off-by: Kevin Brodsky <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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use less confusing names for iov_iter direction initializers

READ/WRITE proved to be actively confusing - the meanings are
"data destination, as used with read(2)" and "data source, as
used with wri

use less confusing names for iov_iter direction initializers

READ/WRITE proved to be actively confusing - the meanings are
"data destination, as used with read(2)" and "data source, as
used with write(2)", but people keep interpreting those as
"we read data from it" and "we write data to it", i.e. exactly
the wrong way.

Call them ITER_DEST and ITER_SOURCE - at least that is harder
to misinterpret...

Signed-off-by: Al Viro <[email protected]>

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net: clear msg_get_inq in __get_compat_msghdr()

syzbot is still complaining uninit-value in tcp_recvmsg(), for
commit 1228b34c8d0ecf6d ("net: clear msg_get_inq in __sys_recvfrom() and
__copy_msghdr_

net: clear msg_get_inq in __get_compat_msghdr()

syzbot is still complaining uninit-value in tcp_recvmsg(), for
commit 1228b34c8d0ecf6d ("net: clear msg_get_inq in __sys_recvfrom() and
__copy_msghdr_from_user()") missed that __get_compat_msghdr() is called
instead of copy_msghdr_from_user() when MSG_CMSG_COMPAT is specified.

Signed-off-by: Tetsuo Handa <[email protected]>
Fixes: 1228b34c8d0ecf6d ("net: clear msg_get_inq in __sys_recvfrom() and __copy_msghdr_from_user()")
Reviewed-by: Jens Axboe <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

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net: fix compat pointer in get_compat_msghdr()

A previous change enabled external users to copy the data before
calling __get_compat_msghdr(), but didn't modify get_compat_msghdr() or
__io_compat_re

net: fix compat pointer in get_compat_msghdr()

A previous change enabled external users to copy the data before
calling __get_compat_msghdr(), but didn't modify get_compat_msghdr() or
__io_compat_recvmsg_copy_hdr() to take that into account. They are both
stil passing in the __user pointer rather than the copied version.

Ensure we pass in the kernel struct, not the pointer to the user data.

Link: https://lore.kernel.org/all/[email protected]/
Fixes: 1a3e4e94a1b9 ("net: copy from user before calling __get_compat_msghdr")
Reported-by: Marek Szyprowski <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>

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net: copy from user before calling __get_compat_msghdr

this is in preparation for multishot receive from io_uring, where it needs
to have access to the original struct user_msghdr.

functionally thi

net: copy from user before calling __get_compat_msghdr

this is in preparation for multishot receive from io_uring, where it needs
to have access to the original struct user_msghdr.

functionally this should be a no-op.

Acked-by: Paolo Abeni <[email protected]>
Signed-off-by: Dylan Yudaken <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>

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skbuff: carry external ubuf_info in msghdr

Make possible for network in-kernel callers like io_uring to pass in a
custom ubuf_info by setting it in a new field of struct msghdr.

Signed-off-by: Pave

skbuff: carry external ubuf_info in msghdr

Make possible for network in-kernel callers like io_uring to pass in a
custom ubuf_info by setting it in a new field of struct msghdr.

Signed-off-by: Pavel Begunkov <[email protected]>
Signed-off-by: Jakub Kicinski <[email protected]>

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net: Return the correct errno code

When kalloc or kmemdup failed, should return ENOMEM rather than ENOBUF.

Signed-off-by: Zheng Yongjun <[email protected]>
Signed-off-by: David S. Miller <da

net: Return the correct errno code

When kalloc or kmemdup failed, should return ENOMEM rather than ENOBUF.

Signed-off-by: Zheng Yongjun <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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iov_iter: transparently handle compat iovecs in import_iovec

Use in compat_syscall to import either native or the compat iovecs, and
remove the now superflous compat_import_iovec.

This removes the

iov_iter: transparently handle compat iovecs in import_iovec

Use in compat_syscall to import either native or the compat iovecs, and
remove the now superflous compat_import_iovec.

This removes the need for special compat logic in most callers, and
the remaining ones can still be simplified by using __import_iovec
with a bool compat parameter.

Signed-off-by: Christoph Hellwig <[email protected]>
Signed-off-by: Al Viro <[email protected]>

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net/scm: Fix typo in SCM_RIGHTS compat refactoring

When refactoring the SCM_RIGHTS code, I accidentally mis-merged my
native/compat diffs, which entirely broke using SCM_RIGHTS in compat
mode. Use t

net/scm: Fix typo in SCM_RIGHTS compat refactoring

When refactoring the SCM_RIGHTS code, I accidentally mis-merged my
native/compat diffs, which entirely broke using SCM_RIGHTS in compat
mode. Use the correct helper.

Reported-by: Christian Zigotzky <[email protected]>
Link: https://lists.ozlabs.org/pipermail/linuxppc-dev/2020-August/216156.html
Reported-by: "Alex Xu (Hello71)" <[email protected]>
Link: https://lore.kernel.org/lkml/1596812929.lz7fuo8r2w.none@localhost/
Suggested-by: Thadeu Lima de Souza Cascardo <[email protected]>
Fixes: c0029de50982 ("net/scm: Regularize compat handling of scm_detach_fds()")
Tested-by: Alex Xu (Hello71) <[email protected]>
Acked-by: Thadeu Lima de Souza Cascardo <[email protected]>
Signed-off-by: Kees Cook <[email protected]>

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fix a braino in cmsghdr_from_user_compat_to_kern()

commit 547ce4cfb34c ("switch cmsghdr_from_user_compat_to_kern() to
copy_from_user()") missed one of the places where ucmlen should've been
replaced

fix a braino in cmsghdr_from_user_compat_to_kern()

commit 547ce4cfb34c ("switch cmsghdr_from_user_compat_to_kern() to
copy_from_user()") missed one of the places where ucmlen should've been
replaced with cmsg.cmsg_len, now that we are fetching the entire struct
rather than doing it field-by-field.

As the result, compat sendmsg() with several different-sized cmsg
attached started to fail with EINVAL. Trivial to fix, fortunately.

Fixes: 547ce4cfb34c ("switch cmsghdr_from_user_compat_to_kern() to copy_from_user()")
Reported-by: Nick Bowler <[email protected]>
Tested-by: Nick Bowler <[email protected]>
Signed-off-by: Al Viro <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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net: remove compat_sys_{get,set}sockopt

Now that the ->compat_{get,set}sockopt proto_ops methods are gone
there is no good reason left to keep the compat syscalls separate.

This fixes the odd use o

net: remove compat_sys_{get,set}sockopt

Now that the ->compat_{get,set}sockopt proto_ops methods are gone
there is no good reason left to keep the compat syscalls separate.

This fixes the odd use of unsigned int for the compat_setsockopt
optlen and the missing sock_use_custom_sol_socket.

It would also easily allow running the eBPF hooks for the compat
syscalls, but such a large change in behavior does not belong into
a consolidation patch like this one.

Signed-off-by: Christoph Hellwig <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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net: simplify cBPF setsockopt compat handling

Add a helper that copies either a native or compat bpf_fprog from
userspace after verifying the length, and remove the compat setsockopt
handlers that n

net: simplify cBPF setsockopt compat handling

Add a helper that copies either a native or compat bpf_fprog from
userspace after verifying the length, and remove the compat setsockopt
handlers that now aren't required.

Signed-off-by: Christoph Hellwig <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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fs: Add receive_fd() wrapper for __receive_fd()

For both pidfd and seccomp, the __user pointer is not used. Update
__receive_fd() to make writing to ufd optional via a NULL check. However,
for the r

fs: Add receive_fd() wrapper for __receive_fd()

For both pidfd and seccomp, the __user pointer is not used. Update
__receive_fd() to make writing to ufd optional via a NULL check. However,
for the receive_fd_user() wrapper, ufd is NULL checked so an -EFAULT
can be returned to avoid changing the SCM_RIGHTS interface behavior. Add
new wrapper receive_fd() for pidfd and seccomp that does not use the ufd
argument. For the new helper, the allocated fd needs to be returned on
success. Update the existing callers to handle it.

Cc: Alexander Viro <[email protected]>
Cc: [email protected]
Reviewed-by: Sargun Dhillon <[email protected]>
Acked-by: Christian Brauner <[email protected]>
Signed-off-by: Kees Cook <[email protected]>

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fs: Move __scm_install_fd() to __receive_fd()

In preparation for users of the "install a received file" logic outside
of net/ (pidfd and seccomp), relocate and rename __scm_install_fd() from
net/cor

fs: Move __scm_install_fd() to __receive_fd()

In preparation for users of the "install a received file" logic outside
of net/ (pidfd and seccomp), relocate and rename __scm_install_fd() from
net/core/scm.c to __receive_fd() in fs/file.c, and provide a wrapper
named receive_fd_user(), as future patches will change the interface
to __receive_fd().

Additionally add a comment to fd_install() as a counterpoint to how
__receive_fd() interacts with fput().

Cc: Alexander Viro <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Jakub Kicinski <[email protected]>
Cc: Dmitry Kadashev <[email protected]>
Cc: Jens Axboe <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Sargun Dhillon <[email protected]>
Cc: Ido Schimmel <[email protected]>
Cc: Ioana Ciornei <[email protected]>
Cc: [email protected]
Cc: [email protected]
Reviewed-by: Sargun Dhillon <[email protected]>
Acked-by: Christian Brauner <[email protected]>
Signed-off-by: Kees Cook <[email protected]>

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net/scm: Regularize compat handling of scm_detach_fds()

Duplicate the cleanups from commit 2618d530dd8b ("net/scm: cleanup
scm_detach_fds") into the compat code.

Replace open-coded __receive_sock()

net/scm: Regularize compat handling of scm_detach_fds()

Duplicate the cleanups from commit 2618d530dd8b ("net/scm: cleanup
scm_detach_fds") into the compat code.

Replace open-coded __receive_sock() with a call to the helper.

Move the check added in commit 1f466e1f15cf ("net: cleanly handle kernel
vs user buffers for ->msg_control") to before the compat call, even
though it should be impossible for an in-kernel call to also be compat.

Correct the int "flags" argument to unsigned int to match fd_install()
and similar APIs.

Regularize any remaining differences, including a whitespace issue,
a checkpatch warning, and add the check from commit 6900317f5eff ("net,
scm: fix PaX detected msg_controllen overflow in scm_detach_fds") which
fixed an overflow unique to 64-bit. To avoid confusion when comparing
the compat handler to the native handler, just include the same check
in the compat handler.

Cc: Christoph Hellwig <[email protected]>
Cc: Sargun Dhillon <[email protected]>
Cc: Jakub Kicinski <[email protected]>
Cc: [email protected]
Cc: [email protected]
Acked-by: Christian Brauner <[email protected]>
Signed-off-by: Kees Cook <[email protected]>

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net/compat: Add missing sock updates for SCM_RIGHTS

Add missed sock updates to compat path via a new helper, which will be
used more in coming patches. (The net/core/scm.c code is left as-is here
to

net/compat: Add missing sock updates for SCM_RIGHTS

Add missed sock updates to compat path via a new helper, which will be
used more in coming patches. (The net/core/scm.c code is left as-is here
to assist with -stable backports for the compat path.)

Cc: Christoph Hellwig <[email protected]>
Cc: Sargun Dhillon <[email protected]>
Cc: Jakub Kicinski <[email protected]>
Cc: [email protected]
Fixes: 48a87cc26c13 ("net: netprio: fd passed in SCM_RIGHTS datagram not set correctly")
Fixes: d84295067fc7 ("net: net_cls: fd passed in SCM_RIGHTS datagram not set correctly")
Acked-by: Christian Brauner <[email protected]>
Signed-off-by: Kees Cook <[email protected]>

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switch cmsghdr_from_user_compat_to_kern() to copy_from_user()

no point getting compat_cmsghdr field-by-field

Signed-off-by: Al Viro <[email protected]>
Signed-off-by: David S. Miller <davem@d

switch cmsghdr_from_user_compat_to_kern() to copy_from_user()

no point getting compat_cmsghdr field-by-field

Signed-off-by: Al Viro <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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get rid of compat_mc_setsockopt()

not used anymore

Signed-off-by: Al Viro <[email protected]>

get rid of compat_mc_getsockopt()

now we can do MCAST_MSFILTER in compat ->getsockopt() without
playing silly buggers with copying things back and forth.
We can form a native struct group_filter (sa

get rid of compat_mc_getsockopt()

now we can do MCAST_MSFILTER in compat ->getsockopt() without
playing silly buggers with copying things back and forth.
We can form a native struct group_filter (sans the variable-length
tail) on stack, pass that + pointer to the tail of original request
to the helper doing the bulk of the work, then do the rest of
copyout - same as the native getsockopt() does.

Signed-off-by: Al Viro <[email protected]>

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lift compat definitions of mcast [sg]etsockopt requests into net/compat.h

We want to get rid of compat_mc_[sg]etsockopt() and to have that stuff
handled without compat_alloc_user_space(), extra copy

lift compat definitions of mcast [sg]etsockopt requests into net/compat.h

We want to get rid of compat_mc_[sg]etsockopt() and to have that stuff
handled without compat_alloc_user_space(), extra copying through
userland, etc. To do that we'll need ipv4 and ipv6 instances of
->compat_[sg]etsockopt() to manipulate the 32bit variants of mcast
requests, so we need to move the definitions of those out of net/compat.c
and into a public header.

This patch just does a mechanical move to include/net/compat.h

Signed-off-by: Al Viro <[email protected]>

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net: cleanly handle kernel vs user buffers for ->msg_control

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

net: cleanly handle kernel vs user buffers for ->msg_control

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: Christoph Hellwig <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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net: abstract out normal and compat msghdr import

This splits it into two parts, one that imports the message, and one
that imports the iovec. This allows a caller to only do the first part,
and imp

net: abstract out normal and compat msghdr import

This splits it into two parts, one that imports the message, and one
that imports the iovec. This allows a caller to only do the first part,
and import the iovec manually afterwards.

No functional changes in this patch.

Acked-by: David Miller <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>

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y2038: socket: use __kernel_old_timespec instead of timespec

The 'timespec' type definition and helpers like ktime_to_timespec()
or timespec64_to_timespec() should no longer be used in the kernel so

y2038: socket: use __kernel_old_timespec instead of timespec

The 'timespec' type definition and helpers like ktime_to_timespec()
or timespec64_to_timespec() should no longer be used in the kernel so
we can remove them and avoid introducing y2038 issues in new code.

Change the socket code that needs to pass a timespec to user space for
backward compatibility to use __kernel_old_timespec instead. This type
has the same layout but with a clearer defined name.

Slightly reformat tcp_recv_timestamp() for consistency after the removal
of timespec64_to_timespec().

Acked-by: Deepa Dinamani <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>

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