freebsd-skq/sys/sys/ktrace.h
Konstantin Belousov 1e4296c919 Ktracing kevent(2) calls with unusual arguments might leads to an
overly large allocation requests.

When ktrace-ing io, sys_kevent() allocates memory to copy the
requested changes and reported events.  Allocations are sized by the
incoming syscall lengths arguments, which are user-controlled, and
might cause overflow in calculations or too large allocations.

Since io trace chunks are limited by ktr_geniosize, there is no sense
it even trying to satisfy unbounded allocations.  Export ktr_geniosize
and clamp the buffers sizes in advance.

PR:	217435
Reported by:	Tim Newsham <tim.newsham@nccgroup.trust>
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2017-03-12 13:48:24 +00:00

292 lines
7.6 KiB
C

/*-
* Copyright (c) 1988, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)ktrace.h 8.1 (Berkeley) 6/2/93
* $FreeBSD$
*/
#ifndef _SYS_KTRACE_H_
#define _SYS_KTRACE_H_
#include <sys/caprights.h>
/*
* operations to ktrace system call (KTROP(op))
*/
#define KTROP_SET 0 /* set trace points */
#define KTROP_CLEAR 1 /* clear trace points */
#define KTROP_CLEARFILE 2 /* stop all tracing to file */
#define KTROP(o) ((o)&3) /* macro to extract operation */
/*
* flags (ORed in with operation)
*/
#define KTRFLAG_DESCEND 4 /* perform op on all children too */
/*
* ktrace record header
*/
struct ktr_header {
int ktr_len; /* length of buf */
short ktr_type; /* trace record type */
pid_t ktr_pid; /* process id */
char ktr_comm[MAXCOMLEN + 1];/* command name */
struct timeval ktr_time; /* timestamp */
intptr_t ktr_tid; /* was ktr_buffer */
};
/*
* Test for kernel trace point (MP SAFE).
*
* KTRCHECK() just checks that the type is enabled and is only for
* internal use in the ktrace subsystem. KTRPOINT() checks against
* ktrace recursion as well as checking that the type is enabled and
* is the public interface.
*/
#define KTRCHECK(td, type) ((td)->td_proc->p_traceflag & (1 << type))
#define KTRPOINT(td, type) \
(KTRCHECK((td), (type)) && !((td)->td_pflags & TDP_INKTRACE))
#define KTRCHECKDRAIN(td) (!(STAILQ_EMPTY(&(td)->td_proc->p_ktr)))
#define KTRUSERRET(td) do { \
if (KTRCHECKDRAIN(td)) \
ktruserret(td); \
} while (0)
/*
* ktrace record types
*/
/*
* KTR_SYSCALL - system call record
*/
#define KTR_SYSCALL 1
struct ktr_syscall {
short ktr_code; /* syscall number */
short ktr_narg; /* number of arguments */
/*
* followed by ktr_narg register_t
*/
register_t ktr_args[1];
};
/*
* KTR_SYSRET - return from system call record
*/
#define KTR_SYSRET 2
struct ktr_sysret {
short ktr_code;
short ktr_eosys;
int ktr_error;
register_t ktr_retval;
};
/*
* KTR_NAMEI - namei record
*/
#define KTR_NAMEI 3
/* record contains pathname */
/*
* KTR_GENIO - trace generic process i/o
*/
#define KTR_GENIO 4
struct ktr_genio {
int ktr_fd;
enum uio_rw ktr_rw;
/*
* followed by data successfully read/written
*/
};
/*
* KTR_PSIG - trace processed signal
*/
#define KTR_PSIG 5
struct ktr_psig {
int signo;
sig_t action;
int code;
sigset_t mask;
};
/*
* KTR_CSW - trace context switches
*/
#define KTR_CSW 6
struct ktr_csw_old {
int out; /* 1 if switch out, 0 if switch in */
int user; /* 1 if usermode (ivcsw), 0 if kernel (vcsw) */
};
struct ktr_csw {
int out; /* 1 if switch out, 0 if switch in */
int user; /* 1 if usermode (ivcsw), 0 if kernel (vcsw) */
char wmesg[8];
};
/*
* KTR_USER - data coming from userland
*/
#define KTR_USER_MAXLEN 2048 /* maximum length of passed data */
#define KTR_USER 7
/*
* KTR_STRUCT - misc. structs
*/
#define KTR_STRUCT 8
/*
* record contains null-terminated struct name followed by
* struct contents
*/
struct sockaddr;
struct stat;
struct sysentvec;
/*
* KTR_SYSCTL - name of a sysctl MIB
*/
#define KTR_SYSCTL 9
/* record contains null-terminated MIB name */
/*
* KTR_PROCCTOR - trace process creation (multiple ABI support)
*/
#define KTR_PROCCTOR 10
struct ktr_proc_ctor {
u_int sv_flags; /* struct sysentvec sv_flags copy */
};
/*
* KTR_PROCDTOR - trace process destruction (multiple ABI support)
*/
#define KTR_PROCDTOR 11
/*
* KTR_CAPFAIL - trace capability check failures
*/
#define KTR_CAPFAIL 12
enum ktr_cap_fail_type {
CAPFAIL_NOTCAPABLE, /* insufficient capabilities in cap_check() */
CAPFAIL_INCREASE, /* attempt to increase capabilities */
CAPFAIL_SYSCALL, /* disallowed system call */
CAPFAIL_LOOKUP, /* disallowed VFS lookup */
};
struct ktr_cap_fail {
enum ktr_cap_fail_type cap_type;
cap_rights_t cap_needed;
cap_rights_t cap_held;
};
/*
* KTR_FAULT - page fault record
*/
#define KTR_FAULT 13
struct ktr_fault {
vm_offset_t vaddr;
int type;
};
/*
* KTR_FAULTEND - end of page fault record
*/
#define KTR_FAULTEND 14
struct ktr_faultend {
int result;
};
/*
* KTR_DROP - If this bit is set in ktr_type, then at least one event
* between the previous record and this record was dropped.
*/
#define KTR_DROP 0x8000
/*
* kernel trace points (in p_traceflag)
*/
#define KTRFAC_MASK 0x00ffffff
#define KTRFAC_SYSCALL (1<<KTR_SYSCALL)
#define KTRFAC_SYSRET (1<<KTR_SYSRET)
#define KTRFAC_NAMEI (1<<KTR_NAMEI)
#define KTRFAC_GENIO (1<<KTR_GENIO)
#define KTRFAC_PSIG (1<<KTR_PSIG)
#define KTRFAC_CSW (1<<KTR_CSW)
#define KTRFAC_USER (1<<KTR_USER)
#define KTRFAC_STRUCT (1<<KTR_STRUCT)
#define KTRFAC_SYSCTL (1<<KTR_SYSCTL)
#define KTRFAC_PROCCTOR (1<<KTR_PROCCTOR)
#define KTRFAC_PROCDTOR (1<<KTR_PROCDTOR)
#define KTRFAC_CAPFAIL (1<<KTR_CAPFAIL)
#define KTRFAC_FAULT (1<<KTR_FAULT)
#define KTRFAC_FAULTEND (1<<KTR_FAULTEND)
/*
* trace flags (also in p_traceflags)
*/
#define KTRFAC_ROOT 0x80000000 /* root set this trace */
#define KTRFAC_INHERIT 0x40000000 /* pass trace flags to children */
#define KTRFAC_DROP 0x20000000 /* last event was dropped */
#ifdef _KERNEL
void ktrnamei(char *);
void ktrcsw(int, int, const char *);
void ktrpsig(int, sig_t, sigset_t *, int);
void ktrfault(vm_offset_t, int);
void ktrfaultend(int);
void ktrgenio(int, enum uio_rw, struct uio *, int);
void ktrsyscall(int, int narg, register_t args[]);
void ktrsysctl(int *name, u_int namelen);
void ktrsysret(int, int, register_t);
void ktrprocctor(struct proc *);
void ktrprocexec(struct proc *, struct ucred **, struct vnode **);
void ktrprocexit(struct thread *);
void ktrprocfork(struct proc *, struct proc *);
void ktruserret(struct thread *);
void ktrstruct(const char *, void *, size_t);
void ktrcapfail(enum ktr_cap_fail_type, const cap_rights_t *,
const cap_rights_t *);
#define ktrcaprights(s) \
ktrstruct("caprights", (s), sizeof(cap_rights_t))
#define ktritimerval(s) \
ktrstruct("itimerval", (s), sizeof(struct itimerval))
#define ktrsockaddr(s) \
ktrstruct("sockaddr", (s), ((struct sockaddr *)(s))->sa_len)
#define ktrstat(s) \
ktrstruct("stat", (s), sizeof(struct stat))
extern u_int ktr_geniosize;
#else
#include <sys/cdefs.h>
__BEGIN_DECLS
int ktrace(const char *, int, int, pid_t);
int utrace(const void *, size_t);
__END_DECLS
#endif
#endif