Even though not all race conditions can be fixed if the 'e' option is not
used, still fix some race conditions using pipe2():
* Prevent both ends of the pipe from leaking to a concurrent popen().
* Prevent the child process's end of the pipe from leaking to any concurrent
fork and exec.
This change also simplifies the code.
The accept(2) man page warns that O_NONBLOCK and other properties on the
new socket may vary across implementations. However, this issue only
applies to accept() and not to accept4(). On the other hand, accept4()
is not commonly available yet.
Reported by: pluknet
Reviewed by: bjk
Approved by: re (kib)
exhausted.
- Add a new protect(1) command that can be used to set or revoke protection
from arbitrary processes. Similar to ktrace it can apply a change to all
existing descendants of a process as well as future descendants.
- Add a new procctl(2) system call that provides a generic interface for
control operations on processes (as opposed to the debugger-specific
operations provided by ptrace(2)). procctl(2) uses a combination of
idtype_t and an id to identify the set of processes on which to operate
similar to wait6().
- Add a PROC_SPROTECT control operation to manage the protection status
of a set of processes. MADV_PROTECT still works for backwards
compatability.
- Add a p_flag2 to struct proc (and a corresponding ki_flag2 to kinfo_proc)
the first bit of which is used to track if P_PROTECT should be inherited
by new child processes.
Reviewed by: kib, jilles (earlier version)
Approved by: re (delphij)
MFC after: 1 month
an address in the first 2GB of the process's address space. This flag should
have the same semantics as the same flag on Linux.
To facilitate this, add a new parameter to vm_map_find() that specifies an
optional maximum virtual address. While here, fix several callers of
vm_map_find() to use a VMFS_* constant for the findspace argument instead of
TRUE and FALSE.
Reviewed by: alc
Approved by: re (kib)
This change avoids undesirably passing some internal file descriptors to a
process created (fork+exec) by another thread.
Kernel support for SOCK_CLOEXEC was added in r248534, March 19, 2013.
Austin Group issue #411 requires 'e' to be accepted before and after 'x',
and encourages accepting the characters in any order, except the initial
'r', 'w' or 'a'.
Given that glibc accepts the characters after r/w/a in any order and that
diagnosing this problem may be hard, change our libc to behave that way as
well.
in the future in a backward compatible (API and ABI) way.
The cap_rights_t represents capability rights. We used to use one bit to
represent one right, but we are running out of spare bits. Currently the new
structure provides place for 114 rights (so 50 more than the previous
cap_rights_t), but it is possible to grow the structure to hold at least 285
rights, although we can make it even larger if 285 rights won't be enough.
The structure definition looks like this:
struct cap_rights {
uint64_t cr_rights[CAP_RIGHTS_VERSION + 2];
};
The initial CAP_RIGHTS_VERSION is 0.
The top two bits in the first element of the cr_rights[] array contain total
number of elements in the array - 2. This means if those two bits are equal to
0, we have 2 array elements.
The top two bits in all remaining array elements should be 0.
The next five bits in all array elements contain array index. Only one bit is
used and bit position in this five-bits range defines array index. This means
there can be at most five array elements in the future.
To define new right the CAPRIGHT() macro must be used. The macro takes two
arguments - an array index and a bit to set, eg.
#define CAP_PDKILL CAPRIGHT(1, 0x0000000000000800ULL)
We still support aliases that combine few rights, but the rights have to belong
to the same array element, eg:
#define CAP_LOOKUP CAPRIGHT(0, 0x0000000000000400ULL)
#define CAP_FCHMOD CAPRIGHT(0, 0x0000000000002000ULL)
#define CAP_FCHMODAT (CAP_FCHMOD | CAP_LOOKUP)
There is new API to manage the new cap_rights_t structure:
cap_rights_t *cap_rights_init(cap_rights_t *rights, ...);
void cap_rights_set(cap_rights_t *rights, ...);
void cap_rights_clear(cap_rights_t *rights, ...);
bool cap_rights_is_set(const cap_rights_t *rights, ...);
bool cap_rights_is_valid(const cap_rights_t *rights);
void cap_rights_merge(cap_rights_t *dst, const cap_rights_t *src);
void cap_rights_remove(cap_rights_t *dst, const cap_rights_t *src);
bool cap_rights_contains(const cap_rights_t *big, const cap_rights_t *little);
Capability rights to the cap_rights_init(), cap_rights_set(),
cap_rights_clear() and cap_rights_is_set() functions are provided by
separating them with commas, eg:
cap_rights_t rights;
cap_rights_init(&rights, CAP_READ, CAP_WRITE, CAP_FSTAT);
There is no need to terminate the list of rights, as those functions are
actually macros that take care of the termination, eg:
#define cap_rights_set(rights, ...) \
__cap_rights_set((rights), __VA_ARGS__, 0ULL)
void __cap_rights_set(cap_rights_t *rights, ...);
Thanks to using one bit as an array index we can assert in those functions that
there are no two rights belonging to different array elements provided
together. For example this is illegal and will be detected, because CAP_LOOKUP
belongs to element 0 and CAP_PDKILL to element 1:
cap_rights_init(&rights, CAP_LOOKUP | CAP_PDKILL);
Providing several rights that belongs to the same array's element this way is
correct, but is not advised. It should only be used for aliases definition.
This commit also breaks compatibility with some existing Capsicum system calls,
but I see no other way to do that. This should be fine as Capsicum is still
experimental and this change is not going to 9.x.
Sponsored by: The FreeBSD Foundation
As mentioned in r16117 and the book "Advanced Programming in the Unix
Environment" by W. Richard Stevens, we should ignore SIGINT and SIGQUIT
before forking, since it is not guaranteed that the parent process starts
running soon enough.
To avoid calling sigaction() in the vforked child, instead block SIGINT and
SIGQUIT before vfork() and keep the sigaction() to ignore after vfork(). The
FreeBSD kernel discards ignored signals, even if they are blocked;
therefore, it is not necessary to unblock SIGINT and SIGQUIT earlier.
This ensures strerror() and friends continue to work correctly even if a
(non-PIE) executable linked against an older libc imports sys_errlist (which
causes sys_errlist to refer to the executable's copy with a size fixed when
that executable was linked).
The executable's use of sys_errlist remains broken because it uses the
current value of sys_nerr and may access past the bounds of the array.
Different from the message "Using sys_errlist from executables is not
ABI-stable" on freebsd-arch, this change does not affect the static library.
There seems no reason to prevent overriding the error messages in the static
library.
and CIFS file attributes as BSD stat(2) flags.
This work is intended to be compatible with ZFS, the Solaris CIFS
server's interaction with ZFS, somewhat compatible with MacOS X,
and of course compatible with Windows.
The Windows attributes that are implemented were chosen based on
the attributes that ZFS already supports.
The summary of the flags is as follows:
UF_SYSTEM: Command line name: "system" or "usystem"
ZFS name: XAT_SYSTEM, ZFS_SYSTEM
Windows: FILE_ATTRIBUTE_SYSTEM
This flag means that the file is used by the
operating system. FreeBSD does not enforce any
special handling when this flag is set.
UF_SPARSE: Command line name: "sparse" or "usparse"
ZFS name: XAT_SPARSE, ZFS_SPARSE
Windows: FILE_ATTRIBUTE_SPARSE_FILE
This flag means that the file is sparse. Although
ZFS may modify this in some situations, there is
not generally any special handling for this flag.
UF_OFFLINE: Command line name: "offline" or "uoffline"
ZFS name: XAT_OFFLINE, ZFS_OFFLINE
Windows: FILE_ATTRIBUTE_OFFLINE
This flag means that the file has been moved to
offline storage. FreeBSD does not have any special
handling for this flag.
UF_REPARSE: Command line name: "reparse" or "ureparse"
ZFS name: XAT_REPARSE, ZFS_REPARSE
Windows: FILE_ATTRIBUTE_REPARSE_POINT
This flag means that the file is a Windows reparse
point. ZFS has special handling code for reparse
points, but we don't currently have the other
supporting infrastructure for them.
UF_HIDDEN: Command line name: "hidden" or "uhidden"
ZFS name: XAT_HIDDEN, ZFS_HIDDEN
Windows: FILE_ATTRIBUTE_HIDDEN
This flag means that the file may be excluded from
a directory listing if the application honors it.
FreeBSD has no special handling for this flag.
The name and bit definition for UF_HIDDEN are
identical to the definition in MacOS X.
UF_READONLY: Command line name: "urdonly", "rdonly", "readonly"
ZFS name: XAT_READONLY, ZFS_READONLY
Windows: FILE_ATTRIBUTE_READONLY
This flag means that the file may not written or
appended, but its attributes may be changed.
ZFS currently enforces this flag, but Illumos
developers have discussed disabling enforcement.
The behavior of this flag is different than MacOS X.
MacOS X uses UF_IMMUTABLE to represent the DOS
readonly permission, but that flag has a stronger
meaning than the semantics of DOS readonly permissions.
UF_ARCHIVE: Command line name: "uarch", "uarchive"
ZFS_NAME: XAT_ARCHIVE, ZFS_ARCHIVE
Windows name: FILE_ATTRIBUTE_ARCHIVE
The UF_ARCHIVED flag means that the file has changed and
needs to be archived. The meaning is same as
the Windows FILE_ATTRIBUTE_ARCHIVE attribute, and
the ZFS XAT_ARCHIVE and ZFS_ARCHIVE attribute.
msdosfs and ZFS have special handling for this flag.
i.e. they will set it when the file changes.
sys/param.h: Bump __FreeBSD_version to 1000047 for the
addition of new stat(2) flags.
chflags.1: Document the new command line flag names
(e.g. "system", "hidden") available to the
user.
ls.1: Reference chflags(1) for a list of file flags
and their meanings.
strtofflags.c: Implement the mapping between the new
command line flag names and new stat(2)
flags.
chflags.2: Document all of the new stat(2) flags, and
explain the intended behavior in a little
more detail. Explain how they map to
Windows file attributes.
Different filesystems behave differently
with respect to flags, so warn the
application developer to take care when
using them.
zfs_vnops.c: Add support for getting and setting the
UF_ARCHIVE, UF_READONLY, UF_SYSTEM, UF_HIDDEN,
UF_REPARSE, UF_OFFLINE, and UF_SPARSE flags.
All of these flags are implemented using
attributes that ZFS already supports, so
the on-disk format has not changed.
ZFS currently doesn't allow setting the
UF_REPARSE flag, and we don't really have
the other infrastructure to support reparse
points.
msdosfs_denode.c,
msdosfs_vnops.c: Add support for getting and setting
UF_HIDDEN, UF_SYSTEM and UF_READONLY
in MSDOSFS.
It supported SF_ARCHIVED, but this has been
changed to be UF_ARCHIVE, which has the same
semantics as the DOS archive attribute instead
of inverse semantics like SF_ARCHIVED.
After discussion with Bruce Evans, change
several things in the msdosfs behavior:
Use UF_READONLY to indicate whether a file
is writeable instead of file permissions, but
don't actually enforce it.
Refuse to change attributes on the root
directory, because it is special in FAT
filesystems, but allow most other attribute
changes on directories.
Don't set the archive attribute on a directory
when its modification time is updated.
Windows and DOS don't set the archive attribute
in that scenario, so we are now bug-for-bug
compatible.
smbfs_node.c,
smbfs_vnops.c: Add support for UF_HIDDEN, UF_SYSTEM,
UF_READONLY and UF_ARCHIVE in SMBFS.
This is similar to changes that Apple has
made in their version of SMBFS (as of
smb-583.8, posted on opensource.apple.com),
but not quite the same.
We map SMB_FA_READONLY to UF_READONLY,
because UF_READONLY is intended to match
the semantics of the DOS readonly flag.
The MacOS X code maps both UF_IMMUTABLE
and SF_IMMUTABLE to SMB_FA_READONLY, but
the immutable flags have stronger meaning
than the DOS readonly bit.
stat.h: Add definitions for UF_SYSTEM, UF_SPARSE,
UF_OFFLINE, UF_REPARSE, UF_ARCHIVE, UF_READONLY
and UF_HIDDEN.
The definition of UF_HIDDEN is the same as
the MacOS X definition.
Add commented-out definitions of
UF_COMPRESSED and UF_TRACKED. They are
defined in MacOS X (as of 10.8.2), but we
do not implement them (yet).
ufs_vnops.c: Add support for getting and setting
UF_ARCHIVE, UF_HIDDEN, UF_OFFLINE, UF_READONLY,
UF_REPARSE, UF_SPARSE, and UF_SYSTEM in UFS.
Alphabetize the flags that are supported.
These new flags are only stored, UFS does
not take any action if the flag is set.
Sponsored by: Spectra Logic
Reviewed by: bde (earlier version)
function, but returns directory file descriptor instead of closing it.
Submitted by: Mariusz Zaborski <oshogbo@FreeBSD.org>
Sponsored by: Google Summer of Code 2013
The variable _logname_valid is not exported via the version script;
therefore, change C and i386/amd64 assembler code to remove indirection
(which allowed interposition). This makes the code slightly smaller and
faster.
Also, remove #define PIC_GOT from i386/amd64 in !PIC mode. Without PIC,
there is no place containing the address of each variable, so there is no
possible definition for PIC_GOT.
address alignment of mappings.
- MAP_ALIGNED(n) requests a mapping aligned on a boundary of (1 << n).
Requests for n >= number of bits in a pointer or less than the size of
a page fail with EINVAL. This matches the API provided by NetBSD.
- MAP_ALIGNED_SUPER is a special case of MAP_ALIGNED. It can be used
to optimize the chances of using large pages. By default it will align
the mapping on a large page boundary (the system is free to choose any
large page size to align to that seems best for the mapping request).
However, if the object being mapped is already using large pages, then
it will align the virtual mapping to match the existing large pages in
the object instead.
- Internally, VMFS_ALIGNED_SPACE is now renamed to VMFS_SUPER_SPACE, and
VMFS_ALIGNED_SPACE(n) is repurposed for specifying a specific alignment.
MAP_ALIGNED(n) maps to using VMFS_ALIGNED_SPACE(n), while
MAP_ALIGNED_SUPER maps to VMFS_SUPER_SPACE.
- mmap() of a device object now uses VMFS_OPTIMAL_SPACE rather than
explicitly using VMFS_SUPER_SPACE. All device objects are forced to
use a specific color on creation, so VMFS_OPTIMAL_SPACE is effectively
equivalent.
Reviewed by: alc
MFC after: 1 month
I removed functionality not proposed for POSIX in Austin group issue #411.
A man page (my own) and test cases will follow in later commits.
PR: 176233
Submitted by: Jukka Ukkonen
reports of its impending demise were removed in 2009 (r199257).
However, in 1996 (r16117) system(3) was switched from vfork(2) to
fork(2) based partly on this. Switch back to vfork(2). This has a
dramatic effect in cases of extreme mmap use - such as excessive
abuse (500+) of shared libraries.
popen(3) has used vfork(2) for a while. vfork(2) isn't going anywhere.
extensions and also tried to be link time compatible with ports libiconv.
This splits that functionality and enables the parts that shouldn't
interfere with the port by default.
WITH_ICONV (now on by default) - adds iconv.h, iconv_open(3) etc.
WITH_LIBICONV_COMPAT (off by default) adds the libiconv_open etc API, linker
symbols and even a stub libiconv.so.3 that are good enough to be able
to 'pkg delete -f libiconv' on a running system and reasonably expect it
to work.
I have tortured many machines over the last few days to try and reduce
the possibilities of foot-shooting as much as I can. I've successfully
recompiled to enable and disable the libiconv_compat modes, ports that use
libiconv alongside system iconv etc. If you don't enable the
WITH_LIBICONV_COMPAT switch, they don't share symbol space.
This is an extension of behavior on other system. iconv(3) is a standard
libc interface and libiconv port expects to be able to run alongside it on
systems that have it.
Bumped osreldate.
any character including '\0', but our version replace escaped '\0'
with '\\'.
I.e. fnmatch("\\", "\\", 0) should not match while fnmatch("\\", "", 0)
should (Linux and NetBSD does the same). Was vice versa.
PR: 181129
MFC after: 1 week
bypass mode when src == dst. Unfortunately, there are tools in ports
that pass byte streams through iconv to determine if the encodings
are valid. eg: gettext-0.18.3+.
Disable the optimization and behave like the other implementations.
- NOTE_TRACK has never triggered a NOTE_TRACK event from the parent pid.
If NOTE_FORK is set, the listener will get a NOTE_FORK event from
the parent pid, but not a separate NOTE_TRACK event.
- Explicitly note that the event added to monitor the child process
preserves the fflags from the original event.
- Move the description of NOTE_TRACKERR under NOTE_TRACK as it is not a
bit for the user to set (which is what this list pupports to be).
Also, explicitly note that if an error occurs, the NOTE_CHILD event
will not be generated.
MFC after: 1 week
This should a regression introduced in r253380 if malloc'ed memory
happens to have '=' at the right place.
Reported by: ache
Pointyhat to: me (avg)
MFC after: 1 day
X-MFC with: r253380
mktemp(), mkstemp() and mkdtemp() are available in standard <stdlib.h> and
also in <unistd.h>. Encourage use of the former by listing it in the
synopsis.
but ACM formula we use have internal state (and return value) in the
[1, 0x7ffffffe] range, so our RAND_MAX (0x7fffffff) is never reached
because it is off by one, zero is not reached too.
Correct both RAND_MAX and rand(3) return value, shifting last one
to the 0 by 1 subtracted, resulting POSIXed [0, 0x7ffffffd(=new RAND_MAX)]
range.
2) Add a checks for not overflowing on too big seeds. It may happens on
the machines, where sizeof(unsigned int) > 32 bits.
Reviewed by: bde [1]
MFC after: 2 weeks
a macro with parameters. Remove a __DECONST hack and add consts instead
for gnu libiconv API compatability. This makes it work with things like
devel/boost-libs that expects to use "iconv" as though it were a pointer.
Expose iconv functions as weak symbols as well as their internal
remapped #define names. This is necessary for autoconf compatability -
on Linux it appears that #include <iconv.h> isn't a link time
prerequisite for their version that's built into glibc.
Initialize the pthread rwlock. Note that upstream has three
separate locks. The file-local static lock appears intentional.
I'm using this as a ports-compatible compile-time substitute for
converters/libiconv on one of my personal machines.
real shared object and libssp_nonshared.a.
This was the last showstopper that prevented from enabling SSP for ports
by default. portmgr@ performed a buildworld which showed no significant
breakage with this patch.
Details:
On i386 for PIC objects, gcc uses the __stack_chk_fail_local hidden
symbol instead of calling __stack_chk_fail directly [1]. This happen
not only with our gcc-4.2.1 but also with the latest gcc-4.8. If you
want the very nasty details, see [2].
OTOH the problem doesn't exist on other architectures. It also doesn't
exist with Clang as the latter will somehow manage to create the
function in the object file at compile time (contrary to only
referencing it through a symbol that will be brought in at link time).
In a perfect world, when an object file is compiled with
-fstack-protector, it will be linked into a binary or a DSO with this
same flag as well, so GCC will add libssp_nonshared.a to the linker
command-line. Unfortunately, we don't control softwares in ports and we
may have such broken DSO. This is the whole point of this patch.
You can reproduce the problem on i386 by compiling a source file into an
object file with "-fstack-protector-all -fPIE" and linking it
into a binary without "-fstack-protector".
This ld script automatically proposes libssp_nonshared.a along with the
real libc DSO to the linker. It is important to understand that the
object file contained in this library will be pulled in the resulting
binary _only if_ the linker notices one of its symbols is needed (i.e.
one of the SSP symbol is missing).
A theorical performance impact could be when compiling, but my testing
showed less than 0.1% of difference.
[1] For 32-bit code gcc saves the PIC register setup by using
__stack_chk_fail_local hidden function instead of calling
__stack_chk_fail directly. See comment line 19460 in:
src/contrib/gcc/config/i386/i386.c
[2] When compiling a source file to an object file, if you use something
which is external to the compilation unit, GCC doesn't know yet if
this symbol will be inside or outside the DSO. So it expects the
worst case and routes the symbol through the GOT, which means
additional space and extra relocation for rtld(1).
Declaring a symbol has hidden tells GCC to use the optimal route (no
GOT), but on the other hand this means the symbol has to be provided
in the same DSO (namely libssp_nonshared.a).
On i386, GCC actually uses an hidden symbol for SSP in PIC objects
to save PIC register setup, as said in [1].
PR: ports/138228
PR: ports/168010
Reviewed by: kib, kan
Store/restore the VFP registers in setjmp/longjmp on ARM EABI if VFP is
enabled in the kernel. It checks the hw.floatingpoint sysctl to see if
floating-point is available and uses this to determine if it should store
them. If it does it uses a different magic value so longjmp is able to know
if it should load them.
with merge the functions but leave out the code to save/load the VFP
registers as that requires other changes to ensure the VFP is enabled
first.
This removes storing the old fpa registers. These were never fully
supported, and the only user of this code I can find have moved to newer
CPUs which use a VFP.
I initially thought wchar_t was locale independent, but this seems to be
only the case on Linux. This means that we cannot depend on the *wc*()
routines to implement *c16*() and *c32*(). Instead, use the Citrus
libiconv that is part of libc.
I'll see if there is anything I can do to make the existing functions
somewhat useful in case the system is built without libiconv in the
nearby future. If not, I'll simply remove the broken implementations.
Reviewed by: jilles, gabor
Per the NetBSD Foundation statement
Third parties are encouraged to change the license on any files which
have a 4-clause license contributed to the NetBSD Foundation to a
2-clause license.
check_deferred_signal() returns twice, since handle_signal() emulates
the return from the normal signal handler by sigreturn(2)ing the
passed context. Second return is performed on the destroyed stack
frame, because __fillcontextx() has already returned. This causes
undefined and bad behaviour, usually the victim thread gets SIGSEGV.
Avoid nested frame and the need to return from it by doing direct call
to getcontext() in the check_deferred_signal() and using a new private
libc helper __fillcontextx2() to complement the context with the
extended CPU state if the deferred signal is still present.
The __fillcontextx() is now unused, but is kept to allow older
libthr.so to be used with the new libc.
Mark __fillcontextx() as returning twice [1].
Reported by: pgj
Pointy hat to: kib
Discussed with: dim
Tested by: pgj, dim
Suggested by: jilles [1]
MFC after: 1 week
implementations visible for use by applications. The functions $F that
are now weak symbols are:
allocm, calloc, dallocm, free, malloc, malloc_usable_size,
nallocm, posix_memalign, rallocm, realloc, sallocm
The non-weak implementations of $F are exported as __$F.
Submitted by: stevek@juniper.net
Reviewed by: jasone@, kib@
Approved by: jasone@ (jemalloc)
Obtained from: juniper Networks, Inc
- Remove an unneeded variable.
- Fix whitespace bugs.
- Fix typoes in comment.
- Improve string handling a bit. Don't handroll strstr() and don't
terminate a strdup()'ed string. Instead, simply strndup() the part we
need.
If we were already provided a struct _citrus_iconv (e.g. through
iconv_open_into()), we should not call free() in case io_init_context()
fails. Instead, call it on the pointer of the allocated object, which
will be NULL in case of iconv_open_into().
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.
path longer than this.
- Fix an unreached case of check against sizeof buf, which in turn leads
to an off-by-one nul byte write on the stack. The original condition
can never be satisfied because the passed boundary is the maximum value
that can be returned, so code was harmless.
MFC after: 1 month
NetBSD's. This output size limited versions of vis and unvis functions
as well as a set of vis variants that allow arbitrary characters to be
specified for encoding.
Finally, MIME Quoted-Printable encoding as described in RFC 2045 is
supported.
A fork/exec could happen between open and fcntl, leaking a file descriptor.
Using O_CLOEXEC fixes this and as a side effect simplifies the code.
NetBSD already had this (I checked this after making the change myself).
Reviewed by: gabor
The changes were derived from what has been committed to NetBSD, with
modifications. These are:
1. Preserve the existsing GLOB_LIMIT behaviour by including the number
of matches to the set of parameters to limit.
2. Change some of the limits to avoid impacting normal use cases:
GLOB_LIMIT_STRING - change from 65536 to ARG_MAX so that glob(3)
can still provide a full command line of expanded names.
GLOB_LIMIT_STAT - change from 128 to 1024 for no other reason than
that 128 feels too low (it's not a limit that impacts the
behaviour of the test program listed in CVE-2010-2632).
GLOB_LIMIT_PATH - change from 1024 to 65536 so that glob(3) can
still provide a fill command line of expanded names.
3. Protect against buffer overruns when we hit the GLOB_LIMIT_STAT or
GLOB_LIMIT_READDIR limits. We append SEP and EOS to pathend in
those cases. Return GLOB_ABORTED instead of GLOB_NOSPACE when we
would otherwise overrun the buffer.
This change also modifies the existing behaviour of glob(3) in case
GLOB_LIMIT is specifies by limiting the *new* matches and not all
matches. This is an important distinction when GLOB_APPEND is set or
when the caller uses a non-zero gl_offs. Previously pre-existing
matches or the value of gl_offs would be counted in the number of
matches even though the man page states that glob(3) would return
GLOB_NOSPACE when gl_matchc or more matches were found.
The limits that cannot be circumvented are GLOB_LIMIT_STRING and
GLOB_LIMIT_PATH all others can be crossed by simply calling glob(3)
again and with GLOB_APPEND set.
The entire description above applies only when GLOB_LIMIT has been
specified of course. No limits apply when this flag isn't set!
Obtained from: Juniper Networks, Inc
equivalent to malloc(size). This eliminates the conditional expression
used for calling either realloc() or malloc() when realloc() will do
all the time.
free and clear the gl_pathv pointer in the glob_t structure. Such
breaks the invariant of the glob_t structure, as stated in the comment
right in front of the globextend() function. If gl_pathv was non-NULL,
then gl_pathc was > 0. Making gl_pathv a NULL pointer without also
setting gl_pathc to 0 is wrong.
Since we otherwise don't free the memory associated with a glob_t in
error cases, it's unlikely that this change will cause a memory leak
that wasn't already there to begin with. Callers of glob(3) must
call globfree(3) irrespective of whether glob(3) returned an error
or not.
This commit adds a new mode option 'e' that must follow any 'b', '+' and/or
'x' options. C11 is clear about the 'x' needing to follow 'b' and/or '+' and
that is what we implement; therefore, require a strict position for 'e' as
well.
For freopen() with a non-NULL path argument and fopen(), the close-on-exec
flag is set iff the 'e' mode option is specified. For freopen() with a NULL
path argument and fdopen(), the close-on-exec flag is turned on if the 'e'
mode option is specified and remains unchanged otherwise.
Although the same behaviour for fopen() can be obtained by open(O_CLOEXEC)
and fdopen(), this needlessly complicates the calling code.
Apart from the ordering requirement, the new option matches glibc.
PR: kern/169320
libc.a and libc_p.a. In addition, define isnan in libm.a and libm_p.a,
but not in libm.so.
This makes it possible to statically link executables using both isnan
and isnanf with libc and libm.
Tested by: kargl
MFC after: 1 week
output and replace it with a new visible sysctl kern.ipc.acceptqueue
of the same functionality. It specifies the maximum length of the
accept queue on a listen socket.
The old kern.ipc.somaxconn remains available for reading and writing
for compatibility reasons so that existing programs, scripts and
configurations continue to work. There no plans to ever remove the
orginal and now hidden kern.ipc.somaxconn.
This adds two features:
* uid_from_user() and gid_from_group() as the reverse of user_from_uid()
and groups_from_gid().
* pwcache_userdb() and pwcache_groupdb() which allow alternative lookup
functions to be used. For example lookups from passwd and group
databases in a non-standard location.
