Commit Graph

220 Commits

Author SHA1 Message Date
emaste
00b67b15b9 Renumber license clauses in sys/kern to avoid skipping #3 2016-09-15 13:16:20 +00:00
gnn
14495cd3b7 Remove unusedd and obsolete openbsd_poll system call. (Phase 1)
Reported by:	brooks
Reviewed by:	brooks,jhb
Differential Revision:	https://reviews.freebsd.org/D7548
2016-08-18 10:50:40 +00:00
rwatson
6c02e936c3 Audit file-descriptor arguments to I/O system calls such as
read(2), write(2), dup(2), and mmap(2).  This auditing is not
required by the Common Criteria (and hence was not being
performed), but is valuable in both contemporary live analysis
and forensic use cases.

MFC after:	3 days
Sponsored by:	DARPA, AFRL
2016-07-10 08:04:02 +00:00
jhb
a0ef1d0d15 Cap IOSIZE_MAX to INT_MAX for 32-bit processes.
Previously, freebsd32 binaries could submit read/write requests with lengths
greater than INT_MAX that a native kernel would have rejected.

Reviewed by:	kib
Sponsored by:	Chelsio Communications
Differential Revision:	https://reviews.freebsd.org/D5788
2016-04-01 18:29:38 +00:00
markj
9abb1836d9 Improve error handling for posix_fallocate(2) and posix_fadvise(2).
- Set td_errno so that ktrace and dtrace can obtain the syscall error
  number in the usual way.
- Pass negative error numbers directly to the syscall layer, as they're
  not intended to be returned to userland.

Reviewed by:	kib
Sponsored by:	EMC / Isilon Storage Division
Differential Revision: https://reviews.freebsd.org/D5425
2016-02-25 19:58:23 +00:00
kib
58e696649e Cover a race between doselwakeup() and selfdfree(). If doselwakeup()
loop finds the selfd entry and clears its sf_si pointer, which is
handled by selfdfree() in parallel, NULL sf_si makes selfdfree() free
the memory.  The result is the race and accesses to the freed memory.

Refcount the selfd ownership.  One reference is for the sf_link
linkage, which is unconditionally dereferenced by selfdfree().
Another reference is for sf_threads, both selfdfree() and
doselwakeup() race to deref it, the winner unlinks and than frees the
selfd entry.

Reported by:	Larry Rosenman <ler@lerctr.org>
Tested by:	Larry Rosenman <ler@lerctr.org>, pho
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
2015-07-09 09:22:21 +00:00
kib
2254748ed0 The lseek(2), mmap(2), truncate(2), ftruncate(2), pread(2), and
pwrite(2) syscalls are wrapped to provide compatibility with pre-7.x
kernels which required padding before the off_t parameter.  The
fcntl(2) contains compatibility code to handle kernels before the
struct flock was changed during the 8.x CURRENT development.  The
shims were reasonable to allow easier revert to the older kernel at
that time.

Now, two or three major releases later, shims do not serve any
purpose.  Such old kernels cannot handle current libc, so revert the
compatibility code.

Make padded syscalls support conditional under the COMPAT6 config
option.  For COMPAT32, the syscalls were under COMPAT6 already.

Remove WITHOUT_SYSCALL_COMPAT build option, which only purpose was to
(partially) disable the removed shims.

Reviewed by:	jhb, imp (previous versions)
Discussed with:	peter
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2015-04-18 21:50:13 +00:00
mjg
0a219ba739 filedesc: simplify fget_unlocked & friends
Introduce fget_fcntl which performs appropriate checks when needed.
This removes a branch from fget_unlocked.

Introduce fget_mmap dealing with cap_rights_to_vmprot conversion.
This removes a branch from _fget.

Modify fget_unlocked to pass sequence counter to interested callers so
that they can perform their own checks and make sure the result was
otained from stable & current state.

Reviewed by:	silence on -hackers
2015-02-17 23:54:06 +00:00
hselasky
f4e178e921 Style changes:
- Move two IOCTL related defines to the top of the C-file
- Add more comments describing the recently added IOCTL small size and
small align macros
2014-11-28 09:32:07 +00:00
dchagin
162012051b Add the ppoll() system call.
Export kern_poll() needed by an upcoming Linuxulator change.

Differential Revision:	https://reviews.freebsd.org/D1133
Reviewed by:	kib, wblock
MFC after:	1 month
2014-11-13 05:26:14 +00:00
hselasky
862145edac Simplify logic a bit. Ensure data buffer is properly aligned,
especially for platforms where unaligned access is not allowed. Make
it possible to override the small buffer size.

A simple continuous read string test using libusb showed a reduction
in CPU usage from roughly 10% to less than 1% using a dual-core GHz
CPU, when the malloc() operation was skipped for small buffers.

MFC after:	2 weeks
2014-11-04 11:29:49 +00:00
mjg
82ce21e1bc Provide an on-stack temporary buffer for small ioctl requests. 2014-11-03 07:46:51 +00:00
mjg
d40cc92af6 In selfdfree re-evaulate sf_si after takin the lock.
Otherwise we can race with doselwakeup.

This is a fixup to r273549

Reviewed by:	jhb
Reported by:	everyone and their dog
2014-10-23 19:06:08 +00:00
mjg
b26a2106d9 Avoid taking the lock in selfdfree when not needed. 2014-10-23 15:35:47 +00:00
mjg
d74326bc91 fd: replace fd_nfiles with fd_lastfile where appropriate
fd_lastfile is guaranteed to be the biggest open fd, so when the intent
is to iterate over active fds or lookup one, there is no point in looking
beyond that limit.

Few places are left unpatched for now.

MFC after:	1 week
2014-06-22 01:31:55 +00:00
davide
aeb4d19339 Hide internal details of sbintime_t implementation wrapping INT64_MAX into
SBT_MAX, to make it more robust in case internal type representation will
change in the future. All the consumers were migrated to SBT_MAX and
every new consumer (if any) should from now use this interface.

Requested by:	bapt, jmg, Ryan Lortie (implictly)
Reviewed by:	mav, bde
2014-04-12 23:29:29 +00:00
rwatson
33fdc14c0c Update kernel inclusions of capability.h to use capsicum.h instead; some
further refinement is required as some device drivers intended to be
portable over FreeBSD versions rely on __FreeBSD_version to decide whether
to include capability.h.

MFC after:	3 weeks
2014-03-16 10:55:57 +00:00
pjd
6175f0915f Replace CAP_POLL_EVENT and CAP_POST_EVENT capability rights (which I had
a very hard time to fully understand) with much more intuitive rights:

	CAP_EVENT - when set on descriptor, the descriptor can be monitored
		with syscalls like select(2), poll(2), kevent(2).

	CAP_KQUEUE_EVENT - When set on a kqueue descriptor, the kevent(2)
		syscall can be called on this kqueue to with the eventlist
		argument set to non-NULL value; in other words the given
		kqueue descriptor can be used to monitor other descriptors.
	CAP_KQUEUE_CHANGE - When set on a kqueue descriptor, the kevent(2)
		syscall can be called on this kqueue to with the changelist
		argument set to non-NULL value; in other words it allows to
		modify events monitored with the given kqueue descriptor.

Add alias CAP_KQUEUE, which allows for both CAP_KQUEUE_EVENT and
CAP_KQUEUE_CHANGE.

Add backward compatibility define CAP_POLL_EVENT which is equal to CAP_EVENT.

Sponsored by:	The FreeBSD Foundation
MFC after:	3 days
2013-11-15 19:55:35 +00:00
kib
5e67d6314a By default, allow up to SSIZE_MAX i/o for non-devfs files.
Sponsored by:	The FreeBSD Foundation
Reminded by:	Dmitry Sivachenko <trtrmitya@gmail.com>
MFC after:	1 month
X-MFC-note:	stable/10 only
2013-10-15 06:35:22 +00:00
kib
3dc87905fa Similar to debug.iosize_max_clamp sysctl, introduce
devfs_iosize_max_clamp sysctl, which allows/disables SSIZE_MAX-sized
i/o requests on the devfs files.

Sponsored by:	The FreeBSD Foundation
Reminded by:	Dmitry Sivachenko <trtrmitya@gmail.com>
MFC after:	1 week
2013-10-15 06:33:10 +00:00
sbruno
bf3232d8bb Restore builds on architectures that don't support CAPABILITIES (mips). 2013-09-05 03:46:44 +00:00
pjd
029a6f5d92 Change the cap_rights_t type from uint64_t to a structure that we can extend
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
2013-09-05 00:09:56 +00:00
peter
b08615c213 Help out gcc. clang understands.
sys_generic.c:1510: warning: 'precision' may be used uninitialized
*** [sys_generic.o] Error code 1
2013-06-29 04:35:04 +00:00
davide
0dd1d9c578 - Trim an unused and bogus Makefile for mount_smbfs.
- Reconnect with some minor modifications, in particular now selsocket()
internals are adapted to use sbintime units after recent'ish calloutng
switch.
2013-06-28 21:00:08 +00:00
mav
c6f9be8cf5 Rework overflow checks of r247898 to not let too "intelligent" compiler to
optimize it out.

Submitted by:	bde
2013-03-09 09:07:13 +00:00
mav
eb7c9d2685 Fix time math overflows and improve zero intervals handling in poll(),
select(), nanosleep() and kevent() functions after calloutng changes.

Reported by:	bde
2013-03-06 19:37:38 +00:00
davide
473ef72351 MFcalloutng:
Fix kern_select() and sys_poll() so that they can handle sub-tick
precision for timeouts (in the same fashion it was done for nanosleep()
in r247797).

Sponsored by:	Google Summer of Code 2012, iXsystems inc.
Tested by:	flo, marius, ian, markj, Fabian Keil
2013-03-04 16:41:27 +00:00
pjd
f07ebb8888 Merge Capsicum overhaul:
- 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
2013-03-02 00:53:12 +00:00
kib
c6bad3bef7 Do not force a writer to the devfs file to drain the buffer writes.
Requested and tested by:	Ian Lepore <freebsd@damnhippie.dyndns.org>
MFC after:	2 weeks
2012-12-23 22:43:27 +00:00
attilio
65d8b7120d Disconnect non-MPSAFE SMBFS from the build in preparation for dropping
GIANT from VFS. In addition, disconnect also netsmb, which is a base
requirement for SMBFS.

In the while SMBFS regular users can use FUSE interface and smbnetfs
port to work with their SMBFS partitions.

Also, there are ongoing efforts by vendor to support in-kernel smbfs,
so there are good chances that it will get relinked once properly locked.

This is not targeted for MFC.
2012-10-18 12:04:56 +00:00
davide
163c370e14 The variable 'error' in sys_poll() is initialized in declaration to value
zero but in any case is overwritten by successive copyin(), making the
previous initialization useless. Remove this.
As an added bonus this fixes a style(9) bug.

Discussed with:		kib
Approved by:		gnn (mentor)
MFC after:		3 days
2012-06-17 13:03:50 +00:00
kib
273d08b6bc Instead of incomplete handling of read(2)/write(2) return values that
does not fit into registers, declare that we do not support this case
using CTASSERT(), and remove endianess-unsafe code to split return value
into td_retval.

While there, change the style of the sysctl debug.iosize_max_clamp
definition.

Requested by:	bde
MFC after:	3 weeks
2012-03-04 14:55:37 +00:00
kib
80ae8fe82c Fix found places where uio_resid is truncated to int.
Add the sysctl debug.iosize_max_clamp, enabled by default. Setting the
sysctl to zero allows to perform the SSIZE_MAX-sized i/o requests from
the usermode.

Discussed with:	bde, das (previous versions)
MFC after:	1 month
2012-02-21 01:05:12 +00:00
kib
ca682488f3 To limit amount of the kernel memory allocated, and to optimize the
iteration over the fdsets, kern_select() limits the length of the
fdsets copied in by the last valid file descriptor index. If any bit
is set in a mask above the limit, current implementation ignores the
filedescriptor, instead of returning EBADF.

Fix the issue by scanning the tails of fdset before entering the
select loop and returning EBADF if any bit above last valid
filedescriptor index is set. The performance impact of the additional
check is only imposed on the (somewhat) buggy applications that pass
bad file descriptors to select(2) or pselect(2).

PR:	kern/155606, kern/162379
Discussed with:	cognet, glebius
Tested by:	andreast (powerpc, all 64/32bit ABI combinations, big-endian),
       marius (sparc64, big-endian)
MFC after:    2 weeks
2011-11-13 10:28:01 +00:00
kmacy
99851f359e In order to maximize the re-usability of kernel code in user space this
patch modifies makesyscalls.sh to prefix all of the non-compatibility
calls (e.g. not linux_, freebsd32_) with sys_ and updates the kernel
entry points and all places in the code that use them. It also
fixes an additional name space collision between the kernel function
psignal and the libc function of the same name by renaming the kernel
psignal kern_psignal(). By introducing this change now we will ease future
MFCs that change syscalls.

Reviewed by:	rwatson
Approved by:	re (bz)
2011-09-16 13:58:51 +00:00
attilio
683d7a54ce Fix a deficiency in the selinfo interface:
If a selinfo object is recorded (via selrecord()) and then it is
quickly destroyed, with the waiters missing the opportunity to awake,
at the next iteration they will find the selinfo object destroyed,
causing a PF#.

That happens because the selinfo interface has no way to drain the
waiters before to destroy the registered selinfo object. Also this
race is quite rare to get in practice, because it would require a
selrecord(), a poll request by another thread and a quick destruction
of the selrecord()'ed selinfo object.

Fix this by adding the seldrain() routine which should be called
before to destroy the selinfo objects (in order to avoid such case),
and fix the present cases where it might have already been called.
Sometimes, the context is safe enough to prevent this type of race,
like it happens in device drivers which installs selinfo objects on
poll callbacks. There, the destruction of the selinfo object happens
at driver detach time, when all the filedescriptors should be already
closed, thus there cannot be a race.
For this case, mfi(4) device driver can be set as an example, as it
implements a full correct logic for preventing this from happening.

Sponsored by:	Sandvine Incorporated
Reported by:	rstone
Tested by:	pluknet
Reviewed by:	jhb, kib
Approved by:	re (bz)
MFC after:	3 weeks
2011-08-25 15:51:54 +00:00
jonathan
a76ca2eae7 poll(2) implementation for capabilities.
When calling poll(2) on a capability, unwrap first and then poll the
underlying object.

Approved by: re (kib), mentor (rwatson)
Sponsored by: Google Inc
2011-08-16 14:14:56 +00:00
jonathan
c33150a2f0 Rename CAP_*_KEVENT to CAP_*_EVENT.
Change the names of a couple of capability rights to be less
FreeBSD-specific.

Approved by: re (kib), mentor (rwatson)
Sponsored by: Google Inc
2011-08-12 14:26:47 +00:00
rwatson
4af919b491 Second-to-last commit implementing Capsicum capabilities in the FreeBSD
kernel for FreeBSD 9.0:

Add a new capability mask argument to fget(9) and friends, allowing system
call code to declare what capabilities are required when an integer file
descriptor is converted into an in-kernel struct file *.  With options
CAPABILITIES compiled into the kernel, this enforces capability
protection; without, this change is effectively a no-op.

Some cases require special handling, such as mmap(2), which must preserve
information about the maximum rights at the time of mapping in the memory
map so that they can later be enforced in mprotect(2) -- this is done by
narrowing the rights in the existing max_protection field used for similar
purposes with file permissions.

In namei(9), we assert that the code is not reached from within capability
mode, as we're not yet ready to enforce namespace capabilities there.
This will follow in a later commit.

Update two capability names: CAP_EVENT and CAP_KEVENT become
CAP_POST_KEVENT and CAP_POLL_KEVENT to more accurately indicate what they
represent.

Approved by:	re (bz)
Submitted by:	jonathan
Sponsored by:	Google Inc
2011-08-11 12:30:23 +00:00
kib
9d21e17f07 For some file types, select code registers two selfd structures. E.g.,
for socket, when specified POLLIN|POLLOUT in events, you would have one
selfd registered for receiving socket buffer, and one for sending. Now,
if both events are not ready to fire at the time of the initial scan,
but are simultaneously ready after the sleep, pollrescan() would iterate
over the pollfd struct twice. Since both times revents is not zero,
returned value would be off by one.

Fix this by recalculating the return value in pollout().

PR:	kern/143029
MFC after:	2 weeks
2010-08-28 17:42:08 +00:00
jhb
44b49a3eaa Send SIGPIPE to the thread that issued the offending system call
rather than to the entire process.

Reported by:	Anit Chakraborty
Reviewed by:	kib, deischen (concept)
MFC after:	1 week
2010-06-29 20:44:19 +00:00
kib
890c865dcf Remove PIOLLHUP from the flags used to test for to set exceptfsd
fd_set bits in select(2). It seems that historical behaviour is to not
reporting exception on EOF, and several applications are broken.

Reported by:	Yoshihiko Sarumaru <ysarumaru gmail com>
Discussed with:	bde
PR:	ports/140934
MFC after:	2 weeks
2010-05-21 10:36:29 +00:00
nwhitehorn
142a4d2993 Provide groundwork for 32-bit binary compatibility on non-x86 platforms,
for upcoming 64-bit PowerPC and MIPS support. This renames the COMPAT_IA32
option to COMPAT_FREEBSD32, removes some IA32-specific code from MI parts
of the kernel and enhances the freebsd32 compatibility code to support
big-endian platforms.

Reviewed by:	kib, jhb
2010-03-11 14:49:06 +00:00
kib
08e5013938 Current pselect(3) is implemented in usermode and thus vulnerable to
well-known race condition, which elimination was the reason for the
function appearance in first place. If sigmask supplied as argument to
pselect() enables a signal, the signal might be delivered before thread
called select(2), causing lost wakeup. Reimplement pselect() in kernel,
making change of sigmask and sleep atomic.

Since signal shall be delivered to the usermode, but sigmask restored,
set TDP_OLDMASK and save old mask in td_oldsigmask. The TDP_OLDMASK
should be cleared by ast() in case signal was not gelivered during
syscall execution.

Reviewed by:	davidxu
Tested by:	pho
MFC after:	1 month
2009-10-27 10:55:34 +00:00
kib
91e6a5b3cc kern_select(9) copies fd_set in and out of userspace in quantities of
longs. Since 32bit processes longs are 4 bytes, 64bit kernel may copy in
or out 4 bytes more then the process expected.

Calculate the amount of bytes to copy taking into account size of fd_set
for the current process ABI.

Diagnosed and tested by:	Peter Jeremy <peterjeremy acm org>
Reviewed by:	jhb
MFC after:	1 week
2009-09-09 20:59:01 +00:00
kib
8b1803af93 Fix the conformance of poll(2) for sockets after r195423 by
returning POLLHUP instead of POLLIN for several cases. Now, the
tools/regression/poll results for FreeBSD are closer to that of the
Solaris and Linux.

Also, improve the POSIX conformance by explicitely clearing POLLOUT
when POLLHUP is reported in pollscan(), making the fix global.

Submitted by:	bde
Reviewed by:	rwatson
MFC after:	1 week
2009-08-23 12:44:15 +00:00
rwatson
5260e3a73c Audit file descriptor and command arguments to ioctl(2).
Approved by:	re (audit argument blanket)
MFC after:	1 week
2009-07-02 09:16:25 +00:00
jeff
cd329071c1 - Use fd_lastfile + 1 as the upper bound on nd. This is more correct than
using the size of the descriptor array.
 - A lock is not needed to fetch fd_lastfile.  The results are stale the
   instant it is dropped.
 - Use a private mutex pool for select since the pool mutex is not used
   as a leaf.
 - Fetch the si_mtx pointer first before resorting to hashing to compute
   the mutex address.

Reviewed by:	McKusick
Approved by:	re (kib)
2009-07-01 20:43:46 +00:00
rwatson
da78c9e4a2 Replace AUDIT_ARG() with variable argument macros with a set more more
specific macros for each audit argument type.  This makes it easier to
follow call-graphs, especially for automated analysis tools (such as
fxr).

In MFC, we should leave the existing AUDIT_ARG() macros as they may be
used by third-party kernel modules.

Suggested by:	brooks
Approved by:	re (kib)
Obtained from:	TrustedBSD Project
MFC after:	1 week
2009-06-27 13:58:44 +00:00
jeff
20397e6431 - Implement a lockless file descriptor lookup algorithm in
fget_unlocked().
 - Save old file descriptor tables created on expansion until
   the entire descriptor table is freed so that pointers may be
   followed without regard for expanders.
 - Mark the file zone as NOFREE so we may attempt to reference
   potentially freed files.
 - Convert several fget_locked() users to fget_unlocked().  This
   requires us to manage reference counts explicitly but reduces
   locking overhead in the common case.
2009-05-14 03:24:22 +00:00