system/freebsd-src
system/freebsd-src
1
0
Fork 0
mirror of https://github.com/freebsd/freebsd-src synced 2024-10-02 22:54:52 +00:00
Code Issues Packages Projects Releases Wiki Activity

rights.4: various corrections on capability rights

Browse source 
- A file descriptor obtained from accept(2), accept4(2) and openat(2)
  is not always assigned all capability rights.  Instead, it inherits
  capability rights from the "parent" socket/dir file descriptor.
- getdents(2) and getdirentries(2) requires CAP_READ.
- openat(2) with O_WRONLY|O_TRUNC does not require CAP_SEEK.

Reviewed by: imp
Pull Request: https://github.com/freebsd/freebsd-src/pull/1207
This commit is contained in:
CismonX 2024-04-28 22:48:26 -06:00 committed by Warner Losh
parent 78444b5ade
commit d289382897
2 changed files with 22 additions and 11 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

12
lib/libsys/cap_rights_limit.2
View file

@ -30,7 +30,7 @@
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.Dd March 9, 2023
.Dd April 27, 2024
.Dt CAP_RIGHTS_LIMIT 2
.Os
.Sh NAME
@ -44,20 +44,22 @@
.Fn cap_rights_limit "int fd" "const cap_rights_t *rights"
.Sh DESCRIPTION
When a file descriptor is created by a function such as
.Xr accept 2 ,
.Xr accept4 2 ,
.Xr fhopen 2 ,
.Xr kqueue 2 ,
.Xr mq_open 2 ,
.Xr open 2 ,
.Xr openat 2 ,
.Xr pdfork 2 ,
.Xr pipe 2 ,
.Xr shm_open 2 ,
.Xr socket 2
or
.Xr socketpair 2 ,
it is assigned all capability rights.
it is assigned all capability rights; for
.Xr accept 2 ,
.Xr accept4 2
or
.Xr openat 2 ,
it inherits capability rights from the "parent" file descriptor.
Those rights can be reduced (but never expanded) by using the
.Fn cap_rights_limit
system call.

21
share/man/man4/rights.4
View file

@ -30,7 +30,7 @@
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.Dd March 22, 2024
.Dd April 27, 2024
.Dt RIGHTS 4
.Os
.Sh NAME
@ -38,20 +38,22 @@
.Nd Capsicum capability rights for file descriptors
.Sh DESCRIPTION
When a file descriptor is created by a function such as
.Xr accept 2 ,
.Xr accept4 2 ,
.Xr fhopen 2 ,
.Xr kqueue 2 ,
.Xr mq_open 2 ,
.Xr open 2 ,
.Xr openat 2 ,
.Xr pdfork 2 ,
.Xr pipe 2 ,
.Xr shm_open 2 ,
.Xr socket 2
or
.Xr socketpair 2 ,
it is assigned all capability rights.
it is assigned all capability rights; for
.Xr accept 2 ,
.Xr accept4 2
or
.Xr openat 2 ,
it inherits capability rights from the "parent" file descriptor.
Those rights can be reduced (but never expanded) by using the
.Xr cap_rights_limit 2 ,
.Xr cap_fcntls_limit 2 and
@ -501,7 +503,10 @@ with the
is also required),
.Xr preadv 2
.Dv ( CAP_SEEK
is also required) and related system calls.
is also required),
.Xr getdents 2 ,
.Xr getdirentries 2 ,
and related system calls.
.It Dv CAP_RECV
An alias to
.Dv CAP_READ .
@ -611,6 +616,8 @@ with the
.Dv O_WRONLY
flag, but without the
.Dv O_APPEND
or
.Dv O_TRUNC
flag,
.Dv CAP_SEEK
is also required.
@ -657,6 +664,8 @@ is also required.
.Xr fsync 2 ,
.Xr ftruncate 2 ,
.Xr futimes 2 ,
.Xr getdents 2 ,
.Xr getdirentries 2 ,
.Xr getpeername 2 ,
.Xr getsockname 2 ,
.Xr getsockopt 2 ,