Commit Graph

21 Commits

Author SHA1 Message Date
Bryan Drewery
b76e673f66 Remove unneeded mutex.h include, missed in r287155.
MFC after:	1 week
Sponsored by:	EMC / Isilon Storage Division
2015-11-04 22:49:34 +00:00
Bryan Drewery
243c115e92 Remove unneeded NULL as this is initialized with M_ZERO.
MFC after:	2 weeks
Sponsored by:	EMC / Isilon Storage Division
2015-10-29 23:56:34 +00:00
Bryan Drewery
8183f2e312 Fix filemon locking races.
Convert filemon_lock and struct filemon* lock to sx(9), rather than a
self-rolled reader-writer lock, and hold it for the entire time needed.

At least filemon_lock_write() was not checking for active readers when
it would successfully return with the write lock "held".  This led to
a race with reading entries from filemon_inuse as they were removed.  This
could be seen with QUEUE_MACRO_DEBUG enabled, causing -1 to be read as an
entry rather than a valid struct filemon*.

Fixing filemon_lock_write() to check readers was insufficient to fix the
races.

sx(9) was used as the lock could be held while taking proctree_lock and sleeping
in fo_write.

Sponsored by:	EMC / Isilon Storage Division
MFC after:	2 weeks
2015-08-26 03:44:48 +00:00
Bryan Drewery
8b64fa1e12 Avoid taking proctree_lock and searching parents in wrappers if not needed.
This should help the case where filemon is loaded but not in use.

Sponsored by:	EMC / Isilon Storage Division
MFC after:	2 weeks
2015-08-26 03:37:18 +00:00
Bryan Drewery
9fa45e4864 Remove unneeded inuse list locking in filemon_comment().
Sponsored by:	EMC / Isilon Storage Division
MFC after:	2 weeks
2015-08-26 03:33:34 +00:00
Bryan Drewery
1ab9f216d2 Move common locking for filemon_inuse and struct filemon* to filemon_pid_check().
This keeps the lock for the filemon_inuse list held only while reading
the list.

Sponsored by:	EMC / Isilon Storage Division
MFC after:	2 weeks
2015-08-26 03:32:47 +00:00
Simon J. Gerraty
3df2b1571b sx_sunlock for sx_slock 2015-06-19 17:34:59 +00:00
Simon J. Gerraty
c849fda850 filemon_pid_check needs to hold proctree_lock
Reviewed by:	kib
MFC after:	few days
2015-06-19 17:19:20 +00:00
Simon J. Gerraty
5d93692dde Bump the version since we now handle openat 2015-06-16 23:03:15 +00:00
Simon J. Gerraty
f859e95660 Latest clang uses openat(2).
If the pathname is absolute or dirfd is AT_FDCWD we can
handle it exactly like open(2).
Otherwise we output an A record to indicate that the path of
an open directory needs to be used (earlier in the trace).

Differential Revision:	D2810
Reviewed by: jhb
MFC after: a bit
2015-06-14 16:31:06 +00:00
Robert Watson
4a14441044 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
Pawel Jakub Dawidek
7008be5bd7 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
Hiroki Sato
89cac24e48 - Use pget(PGET_CANDEBUG | PGET_NOTWEXIT) to determine if the specified
PID is valid for monitoring in FILEMON_SET_PID ioctl.

- Set the monitored PID to -1 when the process exits.

Suggested by:	jilles
Tested by:	sjg
MFC after:	3 days
2013-08-06 02:14:30 +00:00
Hiroki Sato
872ce24739 Add p_candebug() check to FILEMON_SET_PID ioctl.
Discussed with:	sjg
MFC after:	3 days
2013-08-02 14:44:11 +00:00
John Baldwin
af13de0f57 Build fix: Only <sys/cdefs.h> should be included before __FBSDID().
<sys/param.h> needs to be included after any "opt_foo.h" headers so it
sees the same set of defined macros as other headers.
2013-06-04 15:35:37 +00:00
David E. O'Brien
f9d4b3926a Match the options of the kernel. 2013-06-04 06:38:01 +00:00
David E. O'Brien
4e359efd5b A little bit easier to read. 2012-10-26 20:24:13 +00:00
David E. O'Brien
93665dfffb Iterate rather than use recursion. We can blow out the kernel stack if there
is a long chain of fork(2)s.
2012-10-26 15:44:29 +00:00
David E. O'Brien
ab4ee4bb75 Desupport pre-FreeBSD 7.1. 2012-10-25 18:39:09 +00:00
Marcel Moolenaar
097f09bb98 There's no need to make filemon specific to i386 and amd64. All
LP64 architectures define elf64_freebsd_sysvec and all ILP32
architectures define elf32_freebsd_sysvec.
2012-07-02 20:36:26 +00:00
David E. O'Brien
eb9aea5ac0 Add the 'filemon' device. 'filemon' is a kernel module that provides a device
interface for processes to record system calls of its children.

Submitted by:	Juniper Networks.
2012-06-04 22:54:19 +00:00