The <uchar.h> header, part of C11, adds a small number of utility
functions for 16/32-bit "universal" characters, which may or may not be
UTF-16/32. As our wchar_t is already ISO 10646, simply add light-weight
wrappers around wcrtomb() and mbrtowc().
While there, also add (non-yet-standard) _l functions, similar to the
ones we already have for the other locale-dependent functions.
Reviewed by: theraven
If 'e' is used, the kernel must support the recently added pipe2() system
call.
The use of pipe2() with O_CLOEXEC also fixes race conditions between
concurrent popen() calls from different threads, even if the close-on-exec
flag on the fd of the returned FILE is later cleared (because popen() closes
all file descriptors from earlier popen() calls in the child process).
Therefore, this approach should be used in all cases when pipe2() can be
assumed present.
The old version of popen() rejects "re" and "we" but treats "r+e" like "r+".
The ability to clear a file descriptor's close-on-exec flag via
posix_spawn_file_actions_adddup2() is in fact proposed in Austin Group issue
#411.
MFC after: 1 week
As per POSIX.1-2008, posix_spawn_file_actions_add* return [EBADF] if a file
descriptor is negative, not [EINVAL]. The bug was only in the manual page;
the code is correct.
MFC after: 1 week
The pipe2() function is similar to pipe() but allows setting FD_CLOEXEC and
O_NONBLOCK (on both sides) as part of the function.
If p points to two writable ints, pipe2(p, 0) is equivalent to pipe(p).
If the pointer is not valid, behaviour differs: pipe2() writes into the
array from the kernel like socketpair() does, while pipe() writes into the
array from an architecture-specific assembler wrapper.
Reviewed by: kan, kib
The accept4() function, compared to accept(), allows setting the new file
descriptor atomically close-on-exec and explicitly controlling the
non-blocking status on the new socket. (Note that the latter point means
that accept() is not equivalent to any form of accept4().)
The linuxulator's accept4 implementation leaves a race window where the new
file descriptor is not close-on-exec because it calls sys_accept(). This
implementation leaves no such race window (by using falloc() flags). The
linuxulator could be fixed and simplified by using the new code.
Like accept(), accept4() is async-signal-safe, a cancellation point and
permitted in capability mode.
There are no getdtablesize() bounds on the file descriptor to be duplicated;
it only has to be open. If the RLIMIT_NOFILE rlimit was decreased after
opening the file descriptor, it may be greater than or equal to
getdtablesize() but still valid.
MFC after: 1 week
The functions utx_active_add(), utx_active_remove(), utx_lastlogin_add() and
utx_log_add() set errno to 0 if they are successful. This not only violates
POSIX if pututxline() is successful, but may also overwrite a valid error
with 0 if, for example, utx_lastlogin_add() fails while utx_log_add()
succeeds.
Reviewed by: ed
signal.
- Fix the old ksem implementation for POSIX semaphores to not restart
sem_wait() or sem_timedwait() if interrupted by a signal.
MFC after: 1 week
extattr_set_{fd,file,link} is logically a write(2)-like operation and
should return ssize_t, just like extattr_get_*. Also, the user-space
utility was using an int for the return value of extattr_get_* and
extattr_list_*, both of which return an ssize_t.
MFC after: 1 week
Words in shell script are separated by spaces or tabs independent of the
value of IFS. The value of IFS is only relevant for the result of
substitutions. Therefore, there should be a space between 'wordexp' and the
words to be expanded, not an IFS character.
Paranoia might dictate that the shell ignore IFS from the environment (even
though our sh currently uses it), so do not depend on it in the new test
case.
While almost nobody uses O_ASYNC, and rightly so, the inheritance of the
related properties across accept() is a portability issue like the
inheritance of O_NONBLOCK.
on signed integer overflow wrapping. Otherwise mktime(3) and timegm(3)
can hang, in case the timestamp passed in struct tm is not representable
in a time_t. Specifically, any timestamp after 2038-01-19 03:14:07, in
combination with a 32-bit time_t.
Note that it would be better to change the code to not rely on undefined
behaviour, but it is contributed code, and it is not entirely trivial to
fix the issue properly.
MFC after: 3 days
u_long. Before this change it was of type int for syscalls, but prototypes
in sys/stat.h and documentation for chflags(2) and fchflags(2) (but not
for lchflags(2)) stated that it was u_long. Now some related functions
use u_long type for flags (strtofflags(3), fflagstostr(3)).
- Make path argument of type 'const char *' for consistency.
Discussed on: arch
Sponsored by: The FreeBSD Foundation
This change allows creating file descriptors with close-on-exec set in some
situations. SOCK_CLOEXEC and SOCK_NONBLOCK can be OR'ed in socket() and
socketpair()'s type parameter, and MSG_CMSG_CLOEXEC to recvmsg() makes file
descriptors (SCM_RIGHTS) atomically close-on-exec.
The numerical values for SOCK_CLOEXEC and SOCK_NONBLOCK are as in NetBSD.
MSG_CMSG_CLOEXEC is the first free bit for MSG_*.
The SOCK_* flags are not passed to MAC because this may cause incorrect
failures and can be done later via fcntl() anyway. On the other hand, audit
is expected to cope with the new flags.
For MSG_CMSG_CLOEXEC, unp_externalize() is extended to take a flags
argument.
Reviewed by: kib
multibyte support[0] and the new functions strenvisx and strsenvisx.
Add MLINKS for vis(3) functions add by this and the initial import from
NetBSD[1].
PR: bin/166364, bin/175418
Submitted by: "J.R. Oldroyd" <fbsd@opal.com>[0]
stefanf[1]
Obtained from: NetBSD
MFC after: 2 weeks
It is almost always a bug if nscd closes the connection unexpectedly but
programs should not be killed with SIGPIPE for it.
Reviewed by: bushman
Tested by: Jan Beich
MFC after: 1 week
int bindat(int fd, int s, const struct sockaddr *addr, socklen_t addrlen);
int connectat(int fd, int s, const struct sockaddr *name, socklen_t namelen);
which allow to bind and connect respectively to a UNIX domain socket with a
path relative to the directory associated with the given file descriptor 'fd'.
- Add manual pages for the new syscalls.
- Make the new syscalls available for processes in capability mode sandbox.
- Add capability rights CAP_BINDAT and CAP_CONNECTAT that has to be present on
the directory descriptor for the syscalls to work.
- Update audit(4) to support those two new syscalls and to handle path
in sockaddr_un structure relative to the given directory descriptor.
- Update procstat(1) to recognize the new capability rights.
- Document the new capability rights in cap_rights_limit(2).
Sponsored by: The FreeBSD Foundation
Discussed with: rwatson, jilles, kib, des
- Capability is no longer separate descriptor type. Now every descriptor
has set of its own capability rights.
- The cap_new(2) system call is left, but it is no longer documented and
should not be used in new code.
- The new syscall cap_rights_limit(2) should be used instead of
cap_new(2), which limits capability rights of the given descriptor
without creating a new one.
- The cap_getrights(2) syscall is renamed to cap_rights_get(2).
- If CAP_IOCTL capability right is present we can further reduce allowed
ioctls list with the new cap_ioctls_limit(2) syscall. List of allowed
ioctls can be retrived with cap_ioctls_get(2) syscall.
- If CAP_FCNTL capability right is present we can further reduce fcntls
that can be used with the new cap_fcntls_limit(2) syscall and retrive
them with cap_fcntls_get(2).
- To support ioctl and fcntl white-listing the filedesc structure was
heavly modified.
- The audit subsystem, kdump and procstat tools were updated to
recognize new syscalls.
- Capability rights were revised and eventhough I tried hard to provide
backward API and ABI compatibility there are some incompatible changes
that are described in detail below:
CAP_CREATE old behaviour:
- Allow for openat(2)+O_CREAT.
- Allow for linkat(2).
- Allow for symlinkat(2).
CAP_CREATE new behaviour:
- Allow for openat(2)+O_CREAT.
Added CAP_LINKAT:
- Allow for linkat(2). ABI: Reuses CAP_RMDIR bit.
- Allow to be target for renameat(2).
Added CAP_SYMLINKAT:
- Allow for symlinkat(2).
Removed CAP_DELETE. Old behaviour:
- Allow for unlinkat(2) when removing non-directory object.
- Allow to be source for renameat(2).
Removed CAP_RMDIR. Old behaviour:
- Allow for unlinkat(2) when removing directory.
Added CAP_RENAMEAT:
- Required for source directory for the renameat(2) syscall.
Added CAP_UNLINKAT (effectively it replaces CAP_DELETE and CAP_RMDIR):
- Allow for unlinkat(2) on any object.
- Required if target of renameat(2) exists and will be removed by this
call.
Removed CAP_MAPEXEC.
CAP_MMAP old behaviour:
- Allow for mmap(2) with any combination of PROT_NONE, PROT_READ and
PROT_WRITE.
CAP_MMAP new behaviour:
- Allow for mmap(2)+PROT_NONE.
Added CAP_MMAP_R:
- Allow for mmap(PROT_READ).
Added CAP_MMAP_W:
- Allow for mmap(PROT_WRITE).
Added CAP_MMAP_X:
- Allow for mmap(PROT_EXEC).
Added CAP_MMAP_RW:
- Allow for mmap(PROT_READ | PROT_WRITE).
Added CAP_MMAP_RX:
- Allow for mmap(PROT_READ | PROT_EXEC).
Added CAP_MMAP_WX:
- Allow for mmap(PROT_WRITE | PROT_EXEC).
Added CAP_MMAP_RWX:
- Allow for mmap(PROT_READ | PROT_WRITE | PROT_EXEC).
Renamed CAP_MKDIR to CAP_MKDIRAT.
Renamed CAP_MKFIFO to CAP_MKFIFOAT.
Renamed CAP_MKNODE to CAP_MKNODEAT.
CAP_READ old behaviour:
- Allow pread(2).
- Disallow read(2), readv(2) (if there is no CAP_SEEK).
CAP_READ new behaviour:
- Allow read(2), readv(2).
- Disallow pread(2) (CAP_SEEK was also required).
CAP_WRITE old behaviour:
- Allow pwrite(2).
- Disallow write(2), writev(2) (if there is no CAP_SEEK).
CAP_WRITE new behaviour:
- Allow write(2), writev(2).
- Disallow pwrite(2) (CAP_SEEK was also required).
Added convinient defines:
#define CAP_PREAD (CAP_SEEK | CAP_READ)
#define CAP_PWRITE (CAP_SEEK | CAP_WRITE)
#define CAP_MMAP_R (CAP_MMAP | CAP_SEEK | CAP_READ)
#define CAP_MMAP_W (CAP_MMAP | CAP_SEEK | CAP_WRITE)
#define CAP_MMAP_X (CAP_MMAP | CAP_SEEK | 0x0000000000000008ULL)
#define CAP_MMAP_RW (CAP_MMAP_R | CAP_MMAP_W)
#define CAP_MMAP_RX (CAP_MMAP_R | CAP_MMAP_X)
#define CAP_MMAP_WX (CAP_MMAP_W | CAP_MMAP_X)
#define CAP_MMAP_RWX (CAP_MMAP_R | CAP_MMAP_W | CAP_MMAP_X)
#define CAP_RECV CAP_READ
#define CAP_SEND CAP_WRITE
#define CAP_SOCK_CLIENT \
(CAP_CONNECT | CAP_GETPEERNAME | CAP_GETSOCKNAME | CAP_GETSOCKOPT | \
CAP_PEELOFF | CAP_RECV | CAP_SEND | CAP_SETSOCKOPT | CAP_SHUTDOWN)
#define CAP_SOCK_SERVER \
(CAP_ACCEPT | CAP_BIND | CAP_GETPEERNAME | CAP_GETSOCKNAME | \
CAP_GETSOCKOPT | CAP_LISTEN | CAP_PEELOFF | CAP_RECV | CAP_SEND | \
CAP_SETSOCKOPT | CAP_SHUTDOWN)
Added defines for backward API compatibility:
#define CAP_MAPEXEC CAP_MMAP_X
#define CAP_DELETE CAP_UNLINKAT
#define CAP_MKDIR CAP_MKDIRAT
#define CAP_RMDIR CAP_UNLINKAT
#define CAP_MKFIFO CAP_MKFIFOAT
#define CAP_MKNOD CAP_MKNODAT
#define CAP_SOCK_ALL (CAP_SOCK_CLIENT | CAP_SOCK_SERVER)
Sponsored by: The FreeBSD Foundation
Reviewed by: Christoph Mallon <christoph.mallon@gmx.de>
Many aspects discussed with: rwatson, benl, jonathan
ABI compatibility discussed with: kib
system call, which has a nice property - it never fails, so it is a bit
easier to use. If there is no support for capability mode in the kernel
the function will return false (not in a sandbox). If the kernel is compiled
with the support for capability mode, the function will return true or false
depending if the calling process is in the capability mode sandbox or not
respectively.
Sponsored by: The FreeBSD Foundation
routines provide write-only stdio FILE objects that store their data in a
dynamically allocated buffer. They are a string builder interface somewhat
akin to a completely dynamic sbuf.
Reviewed by: bde, jilles (earlier versions)
MFC after: 1 month
* Reopen the directory using openat(fd, ".", ...) instead of opening the
pathname again. This fixes a race condition where the meaning of the
pathname changes and allows a reopen with fdopendir().
* Always reopen the directory for union stacks, not only when DTF_REWIND
is passed. Applications should be able to fchdir(dirfd(dir)) and
*at(dirfd(dir), ...). DTF_REWIND now does nothing.
example from bsearch(3) too, so that we don't have to duplicate
the example code in both places.
PR: docs/176197
Reviewed by: stefanf
Approved by: remko (mentor), gjb (mentor)
MFC after: 1 week
- Remove unused #include.
- Do not cast away const.
- Use the canonical idiom to compare two numbers.
- Use proper type for sizes, i.e. size_t instead of int.
- Correct indentation.
- Simplify printf("\n") to puts("").
- Use return instead of exit() in main().
Submitted by: Christoph Mallon, christoph.mallon at gmx.de
Approved by: gjb (mentor)
Reviewed by: stefanf
MFC after: 1 week
qsort(3) can work together to sort an array of integers.
PR: docs/176197
Submitted by: Fernando, fapesteguia at opensistemas.com
Approved by: gjb (mentor)
MFC after: 1 week
now disables read-ahead. It used to effectively restore the system default
readahead hueristic if it had been changed; a negative value now restores
the default.
Reviewed by: kib
this is not a problem as they are resolved by libgcc. The exception is for
the __aeabi_mem* functions. These call back into libc to the appropriate
function. This causes issues for static binaries as we only link against
libc once so there is no way for it to call into libgcc and back.
The fix for this is to include these symbols in libc but keep them hidden
so binaries use the libgcc version.
There are uncommon cases where fts_safe_changedir() may be called with a
non-NULL name that is not "..". Do not block or worse if an attacker put (a
(symlink to) a fifo or device where a directory used to be.
MFC after: 1 week
with the user's namespace.
- Correct size and position variables type from long to size_t.
- Do not set errno to ENOMEM on malloc failure, as malloc already does so.
- Implement the concept of "buffer data length", which mandates what SEEK_END
refers to and the allowed extent for a read.
- Use NULL as read-callback if the buffer is opened in write-only mode.
Conversely, use NULL as write-callback when opened in read-only mode.
- Implement the handling of the ``b'' character in the mode argument. A binary
buffer differs from a text buffer (default mode if ``b'' is omitted) in that
NULL bytes are never appended to writes and that the "buffer data length"
equals to the size of the buffer.
- Remove shall from the man page. Use indicative instead. Also, specify that
the ``b'' flag does not conform with POSIX but is supported by glibc.
- Update the regression test so that the ``b'' functionality and the "buffer
data length" concepts are tested.
- Minor style(9) corrections.
Suggested by: jilles
Reviewed by: cognet
Approved by: cognet
but use normal references instead of weak. This makes the statically
linked binaries to use fast gettimeofday(2) by forcing the linker to
resolve references and providing the neccessary functions.
Reported by: bde
Tested by: marius (sparc64)
MFC after: 2 weeks
in r7 and use ip to store the old version of r7 as it is not guaranteed to
be kept when calling a subroutine. The kernel will preserve the register
across system calls.
