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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2021-06-28 19:49:37 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-06-28 19:49:37 -0700 |
| commit | 616ea5cc4a7b058f8c27e37b9a597d8704c49130 (patch) | |
| tree | 7a3a2186026a580de17847f2e574190740a62204 /Documentation | |
| parent | 233a806b00e31b3ab8d57a68f1aab40cf1e5eaea (diff) | |
| parent | 9a03abc16c77062c73972df08206f1031862d9b4 (diff) | |
Merge tag 'seccomp-v5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull seccomp updates from Kees Cook:
- Add "atomic addfd + send reply" mode to SECCOMP_USER_NOTIF to better
handle EINTR races visible to seccomp monitors. (Rodrigo Campos,
Sargun Dhillon)
- Improve seccomp selftests for readability in CI systems. (Kees Cook)
* tag 'seccomp-v5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
selftests/seccomp: Avoid using "sysctl" for report
selftests/seccomp: Flush benchmark output
selftests/seccomp: More closely track fds being assigned
selftests/seccomp: Add test for atomic addfd+send
seccomp: Support atomic "addfd + send reply"
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/userspace-api/seccomp_filter.rst | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/Documentation/userspace-api/seccomp_filter.rst b/Documentation/userspace-api/seccomp_filter.rst index 6efb41cc8072..d61219889e49 100644 --- a/Documentation/userspace-api/seccomp_filter.rst +++ b/Documentation/userspace-api/seccomp_filter.rst @@ -259,6 +259,18 @@ and ``ioctl(SECCOMP_IOCTL_NOTIF_SEND)`` a response, indicating what should be returned to userspace. The ``id`` member of ``struct seccomp_notif_resp`` should be the same ``id`` as in ``struct seccomp_notif``. +Userspace can also add file descriptors to the notifying process via +``ioctl(SECCOMP_IOCTL_NOTIF_ADDFD)``. The ``id`` member of +``struct seccomp_notif_addfd`` should be the same ``id`` as in +``struct seccomp_notif``. The ``newfd_flags`` flag may be used to set flags +like O_EXEC on the file descriptor in the notifying process. If the supervisor +wants to inject the file descriptor with a specific number, the +``SECCOMP_ADDFD_FLAG_SETFD`` flag can be used, and set the ``newfd`` member to +the specific number to use. If that file descriptor is already open in the +notifying process it will be replaced. The supervisor can also add an FD, and +respond atomically by using the ``SECCOMP_ADDFD_FLAG_SEND`` flag and the return +value will be the injected file descriptor number. + It is worth noting that ``struct seccomp_data`` contains the values of register arguments to the syscall, but does not contain pointers to memory. The task's memory is accessible to suitably privileged traces via ``ptrace()`` or |