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| author | Jakub Kicinski <kuba@kernel.org> | 2026-08-17 18:15:01 -0700 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-08-17 18:15:01 -0700 |
| commit | f461b94f1a1bf389dc6b893e194f66ecc86cb20a (patch) | |
| tree | bca616d4c221e53f531775be5bbe228bae8dd4ce /include/uapi | |
| parent | 768af217217bf147429fde629f8d8eedeba49072 (diff) | |
| parent | 5d513ce19de963c7e36904c98d7b02ecd16a30a1 (diff) | |
Merge branch 'net-af_unix-useful-handling-of-lsm-denials-on-scm_rights'
Jori Koolstra says:
====================
net: af_unix: useful handling of LSM denials on SCM_RIGHTS
Right now if some LSM denies an AF_UNIX socket peer to receive a
SCM_RIGHTS fd, the SCM_RIGHTS fd array will be cut short at
that point, and MSG_CTRUNC is set on return of recvmsg(2). This is
highly problematic behaviour, because it leaves the receiver
wondering what happened. As per man page MSG_CTRUNC is supposed to
indicate that the control buffer was sized too short, but suddenly
a permission error might result in the exact same flag being set.
Moreover, the receiver has no chance to determine how many fds got
originally sent and how many were suppressed.[1]
Add a SO_RIGHTS_NOTRUNC option to UNIX sockets to enable more useful
handling of LSM denials when receiving SCM_RIGHTS messages: instead of
truncating the message at the first blocked fd, keep every fd slot
and store the LSM errno in the blocked slot. This option is inherited
by the accept()-ed socket when set on the listen() socket.
[1]: https://github.com/uapi-group/kernel-features#useful-handling-of-lsm-denials-on-scm_rights
====================
Link: https://patch.msgid.link/20260813162818.149248-1-jkoolstra@xs4all.nl
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'include/uapi')
| -rw-r--r-- | include/uapi/asm-generic/socket.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/include/uapi/asm-generic/socket.h b/include/uapi/asm-generic/socket.h index 53b5a8c002b1..84ea7b92936e 100644 --- a/include/uapi/asm-generic/socket.h +++ b/include/uapi/asm-generic/socket.h @@ -150,6 +150,8 @@ #define SO_INQ 84 #define SCM_INQ SO_INQ +#define SO_RIGHTS_NOTRUNC 85 + #if !defined(__KERNEL__) #if __BITS_PER_LONG == 64 || (defined(__x86_64__) && defined(__ILP32__)) |