/*- * Copyright (c) 1989, 1992, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software developed by the Computer Systems * Engineering group at Lawrence Berkeley Laboratory under DARPA contract * BG 91-66 and contributed to Berkeley. * * 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. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. 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. * * $FreeBSD: src/lib/libkvm/kvm_proc.c,v 1.25.2.3 2002/08/24 07:27:46 kris Exp $ * $DragonFly: src/lib/libkvm/kvm_proc.c,v 1.18 2008/06/05 18:06:30 swildner Exp $ * * @(#)kvm_proc.c 8.3 (Berkeley) 9/23/93 */ /* * Proc traversal interface for kvm. ps and w are (probably) the exclusive * users of this code, so we've factored it out into a separate module. * Thus, we keep this grunge out of the other kvm applications (i.e., * most other applications are interested only in open/close/read/nlist). */ #include /* MUST BE FIRST */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "kvm_private.h" #if used static char * kvm_readswap(kvm_t *kd, const struct proc *p, u_long va, u_long *cnt) { #if defined(__FreeBSD__) || defined(__DragonFly__) /* XXX Stubbed out, our vm system is differnet */ _kvm_err(kd, kd->program, "kvm_readswap not implemented"); return(0); #endif } #endif #define KREAD(kd, addr, obj) \ (kvm_read(kd, addr, (char *)(obj), sizeof(*obj)) != sizeof(*obj)) #define KREADSTR(kd, addr) \ kvm_readstr(kd, (u_long)addr, NULL, NULL) static struct kinfo_proc * kinfo_resize_proc(kvm_t *kd, struct kinfo_proc *bp) { if (bp < kd->procend) return bp; size_t pos = bp - kd->procend; size_t size = kd->procend - kd->procbase; if (size == 0) size = 8; else size *= 2; kd->procbase = _kvm_realloc(kd, kd->procbase, sizeof(*bp) * size); if (kd->procbase == NULL) return NULL; kd->procend = kd->procbase + size; bp = kd->procbase + pos; return bp; } /* * note: this function is also used by /usr/src/sys/kern/kern_kinfo.c as * compiled by userland. */ dev_t dev2udev(cdev_t dev) { if (dev == NULL) return NOUDEV; if ((dev->si_umajor & 0xffffff00) || (dev->si_uminor & 0x0000ff00)) { return NOUDEV; } return((dev->si_umajor << 8) | dev->si_uminor); } /* * Helper routine which traverses the left hand side of a red-black sub-tree. */ static uintptr_t kvm_lwptraverse(kvm_t *kd, struct lwp *lwp, uintptr_t lwppos) { for (;;) { if (KREAD(kd, lwppos, lwp)) { _kvm_err(kd, kd->program, "can't read lwp at %p", (void *)lwppos); return ((uintptr_t)-1); } if (lwp->u.lwp_rbnode.rbe_left == NULL) break; lwppos = (uintptr_t)lwp->u.lwp_rbnode.rbe_left; } return(lwppos); } /* * Iterate LWPs in a process. * * The first lwp in a red-black tree is a left-side traversal of the tree. */ static uintptr_t kvm_firstlwp(kvm_t *kd, struct lwp *lwp, struct proc *proc) { return(kvm_lwptraverse(kd, lwp, (uintptr_t)proc->p_lwp_tree.rbh_root)); } /* * If the current element is the left side of the parent the next element * will be a left side traversal of the parent's right side. If the parent * has no right side the next element will be the parent. * * If the current element is the right side of the parent the next element * is the parent. * * If the parent is NULL we are done. */ static uintptr_t kvm_nextlwp(kvm_t *kd, uintptr_t lwppos, struct lwp *lwp, struct proc *proc) { uintptr_t nextpos; nextpos = (uintptr_t)lwp->u.lwp_rbnode.rbe_parent; if (nextpos) { if (KREAD(kd, nextpos, lwp)) { _kvm_err(kd, kd->program, "can't read lwp at %p", (void *)lwppos); return ((uintptr_t)-1); } if (lwppos == (uintptr_t)lwp->u.lwp_rbnode.rbe_left) { /* * If we had gone down the left side the next element * is a left hand traversal of the parent's right * side, or the parent itself if there is no right * side. */ lwppos = (uintptr_t)lwp->u.lwp_rbnode.rbe_right; if (lwppos) nextpos = kvm_lwptraverse(kd, lwp, lwppos); } else { /* * If we had gone down the right side the next * element is the parent. */ /* nextpos = nextpos */ } } return(nextpos); } /* * Read proc's from memory file into buffer bp, which has space to hold * at most maxcnt procs. */ static int kvm_proclist(kvm_t *kd, int what, int arg, struct proc *p, struct kinfo_proc *bp) { struct pgrp pgrp; struct pgrp tpgrp; struct globaldata gdata; struct session sess; struct session tsess; struct tty tty; struct proc proc; struct ucred ucred; struct thread thread; struct proc pproc; struct cdev cdev; struct vmspace vmspace; struct prison prison; struct sigacts sigacts; struct lwp lwp; uintptr_t lwppos; int count; char *wmesg; count = 0; for (; p != NULL; p = proc.p_list.le_next) { if (KREAD(kd, (u_long)p, &proc)) { _kvm_err(kd, kd->program, "can't read proc at %p", p); return (-1); } if (KREAD(kd, (u_long)proc.p_ucred, &ucred)) { _kvm_err(kd, kd->program, "can't read ucred at %p", proc.p_ucred); return (-1); } proc.p_ucred = &ucred; switch(what & ~KERN_PROC_FLAGMASK) { case KERN_PROC_PID: if (proc.p_pid != (pid_t)arg) continue; break; case KERN_PROC_UID: if (ucred.cr_uid != (uid_t)arg) continue; break; case KERN_PROC_RUID: if (ucred.cr_ruid != (uid_t)arg) continue; break; } if (KREAD(kd, (u_long)proc.p_pgrp, &pgrp)) { _kvm_err(kd, kd->program, "can't read pgrp at %p", proc.p_pgrp); return (-1); } proc.p_pgrp = &pgrp; if (proc.p_pptr) { if (KREAD(kd, (u_long)proc.p_pptr, &pproc)) { _kvm_err(kd, kd->program, "can't read pproc at %p", proc.p_pptr); return (-1); } proc.p_pptr = &pproc; } if (proc.p_sigacts) { if (KREAD(kd, (u_long)proc.p_sigacts, &sigacts)) { _kvm_err(kd, kd->program, "can't read sigacts at %p", proc.p_sigacts); return (-1); } proc.p_sigacts = &sigacts; } if (KREAD(kd, (u_long)pgrp.pg_session, &sess)) { _kvm_err(kd, kd->program, "can't read session at %p", pgrp.pg_session); return (-1); } pgrp.pg_session = &sess; if ((proc.p_flags & P_CONTROLT) && sess.s_ttyp != NULL) { if (KREAD(kd, (u_long)sess.s_ttyp, &tty)) { _kvm_err(kd, kd->program, "can't read tty at %p", sess.s_ttyp); return (-1); } sess.s_ttyp = &tty; if (tty.t_dev && tty.t_dev != NULL) { if (KREAD(kd, (u_long)tty.t_dev, &cdev)) tty.t_dev = NULL; else tty.t_dev = &cdev; } if (tty.t_pgrp != NULL) { if (KREAD(kd, (u_long)tty.t_pgrp, &tpgrp)) { _kvm_err(kd, kd->program, "can't read tpgrp at %p", tty.t_pgrp); return (-1); } tty.t_pgrp = &tpgrp; } if (tty.t_session != NULL) { if (KREAD(kd, (u_long)tty.t_session, &tsess)) { _kvm_err(kd, kd->program, "can't read tsess at %p", tty.t_session); return (-1); } tty.t_session = &tsess; } } if (KREAD(kd, (u_long)proc.p_vmspace, &vmspace)) { _kvm_err(kd, kd->program, "can't read vmspace at %p", proc.p_vmspace); return (-1); } proc.p_vmspace = &vmspace; if (ucred.cr_prison != NULL) { if (KREAD(kd, (u_long)ucred.cr_prison, &prison)) { _kvm_err(kd, kd->program, "can't read prison at %p", ucred.cr_prison); return (-1); } ucred.cr_prison = &prison; } switch (what & ~KERN_PROC_FLAGMASK) { case KERN_PROC_PGRP: if (proc.p_pgrp->pg_id != (pid_t)arg) continue; break; case KERN_PROC_TTY: if ((proc.p_flags & P_CONTROLT) == 0 || dev2udev(proc.p_pgrp->pg_session->s_ttyp->t_dev) != (dev_t)arg) continue; break; } if ((bp = kinfo_resize_proc(kd, bp)) == NULL) return (-1); fill_kinfo_proc(&proc, bp); bp->kp_paddr = (uintptr_t)p; lwppos = kvm_firstlwp(kd, &lwp, &proc); if (lwppos == 0) { bp++; /* Just export the proc then */ count++; } while (lwppos && lwppos != (uintptr_t)-1) { if (p != lwp.lwp_proc) { _kvm_err(kd, kd->program, "lwp has wrong parent"); return (-1); } lwp.lwp_proc = &proc; if (KREAD(kd, (u_long)lwp.lwp_thread, &thread)) { _kvm_err(kd, kd->program, "can't read thread at %p", lwp.lwp_thread); return (-1); } lwp.lwp_thread = &thread; if (thread.td_gd) { if (KREAD(kd, (u_long)thread.td_gd, &gdata)) { _kvm_err(kd, kd->program, "can't read" " gd at %p", thread.td_gd); return(-1); } thread.td_gd = &gdata; } if (thread.td_wmesg) { wmesg = (void *)KREADSTR(kd, thread.td_wmesg); if (wmesg == NULL) { _kvm_err(kd, kd->program, "can't read" " wmesg %p", thread.td_wmesg); return(-1); } thread.td_wmesg = wmesg; } else { wmesg = NULL; } if ((bp = kinfo_resize_proc(kd, bp)) == NULL) return (-1); fill_kinfo_proc(&proc, bp); fill_kinfo_lwp(&lwp, &bp->kp_lwp); bp->kp_paddr = (uintptr_t)p; bp++; count++; if (wmesg) free(wmesg); if ((what & KERN_PROC_FLAG_LWP) == 0) break; lwppos = kvm_nextlwp(kd, lwppos, &lwp, &proc); } if (lwppos == (uintptr_t)-1) return(-1); } return (count); } /* * Build proc info array by reading in proc list from a crash dump. * We reallocate kd->procbase as necessary. */ static int kvm_deadprocs(kvm_t *kd, int what, int arg, u_long a_allproc, u_long a_zombproc) { struct kinfo_proc *bp = kd->procbase; int acnt, zcnt; struct proc *p; if (KREAD(kd, a_allproc, &p)) { _kvm_err(kd, kd->program, "cannot read allproc"); return (-1); } acnt = kvm_proclist(kd, what, arg, p, bp); if (acnt < 0) return (acnt); if (KREAD(kd, a_zombproc, &p)) { _kvm_err(kd, kd->program, "cannot read zombproc"); return (-1); } zcnt = kvm_proclist(kd, what, arg, p, bp + acnt); if (zcnt < 0) zcnt = 0; return (acnt + zcnt); } struct kinfo_proc * kvm_getprocs(kvm_t *kd, int op, int arg, int *cnt) { int mib[4], st, nprocs; int miblen = ((op & ~KERN_PROC_FLAGMASK) == KERN_PROC_ALL) ? 3 : 4; size_t size; if (kd->procbase != 0) { free((void *)kd->procbase); /* * Clear this pointer in case this call fails. Otherwise, * kvm_close() will free it again. */ kd->procbase = 0; } if (kvm_ishost(kd)) { size = 0; mib[0] = CTL_KERN; mib[1] = KERN_PROC; mib[2] = op; mib[3] = arg; st = sysctl(mib, miblen, NULL, &size, NULL, 0); if (st == -1) { _kvm_syserr(kd, kd->program, "kvm_getprocs"); return (0); } do { size += size / 10; kd->procbase = (struct kinfo_proc *) _kvm_realloc(kd, kd->procbase, size); if (kd->procbase == 0) return (0); st = sysctl(mib, miblen, kd->procbase, &size, NULL, 0); } while (st == -1 && errno == ENOMEM); if (st == -1) { _kvm_syserr(kd, kd->program, "kvm_getprocs"); return (0); } if (size % sizeof(struct kinfo_proc) != 0) { _kvm_err(kd, kd->program, "proc size mismatch (%zd total, %zd chunks)", size, sizeof(struct kinfo_proc)); return (0); } nprocs = size / sizeof(struct kinfo_proc); } else { struct nlist nl[4], *p; nl[0].n_name = "_nprocs"; nl[1].n_name = "_allproc"; nl[2].n_name = "_zombproc"; nl[3].n_name = 0; if (kvm_nlist(kd, nl) != 0) { for (p = nl; p->n_type != 0; ++p) ; _kvm_err(kd, kd->program, "%s: no such symbol", p->n_name); return (0); } if (KREAD(kd, nl[0].n_value, &nprocs)) { _kvm_err(kd, kd->program, "can't read nprocs"); return (0); } nprocs = kvm_deadprocs(kd, op, arg, nl[1].n_value, nl[2].n_value); #ifdef notdef size = nprocs * sizeof(struct kinfo_proc); (void)realloc(kd->procbase, size); #endif } *cnt = nprocs; return (kd->procbase); } void _kvm_freeprocs(kvm_t *kd) { if (kd->procbase) { free(kd->procbase); kd->procbase = 0; } } void * _kvm_realloc(kvm_t *kd, void *p, size_t n) { void *np = (void *)realloc(p, n); if (np == 0) { free(p); _kvm_err(kd, kd->program, "out of memory"); } return (np); } #ifndef MAX #define MAX(a, b) ((a) > (b) ? (a) : (b)) #endif /* * Read in an argument vector from the user address space of process pid. * addr if the user-space base address of narg null-terminated contiguous * strings. This is used to read in both the command arguments and * environment strings. Read at most maxcnt characters of strings. */ static char ** kvm_argv(kvm_t *kd, pid_t pid, u_long addr, int narg, int maxcnt) { char *np, *cp, *ep, *ap; u_long oaddr = -1; int len, cc; char **argv; /* * Check that there aren't an unreasonable number of agruments, * and that the address is in user space. */ if (narg > 512 || addr < VM_MIN_USER_ADDRESS || addr >= VM_MAX_USER_ADDRESS) { return (0); } /* * kd->argv : work space for fetching the strings from the target * process's space, and is converted for returning to caller */ if (kd->argv == 0) { /* * Try to avoid reallocs. */ kd->argc = MAX(narg + 1, 32); kd->argv = (char **)_kvm_malloc(kd, kd->argc * sizeof(*kd->argv)); if (kd->argv == 0) return (0); } else if (narg + 1 > kd->argc) { kd->argc = MAX(2 * kd->argc, narg + 1); kd->argv = (char **)_kvm_realloc(kd, kd->argv, kd->argc * sizeof(*kd->argv)); if (kd->argv == 0) return (0); } /* * kd->argspc : returned to user, this is where the kd->argv * arrays are left pointing to the collected strings. */ if (kd->argspc == 0) { kd->argspc = (char *)_kvm_malloc(kd, PAGE_SIZE); if (kd->argspc == 0) return (0); kd->arglen = PAGE_SIZE; } /* * kd->argbuf : used to pull in pages from the target process. * the strings are copied out of here. */ if (kd->argbuf == 0) { kd->argbuf = (char *)_kvm_malloc(kd, PAGE_SIZE); if (kd->argbuf == 0) return (0); } /* Pull in the target process'es argv vector */ cc = sizeof(char *) * narg; if (kvm_uread(kd, pid, addr, (char *)kd->argv, cc) != cc) return (0); /* * ap : saved start address of string we're working on in kd->argspc * np : pointer to next place to write in kd->argspc * len: length of data in kd->argspc * argv: pointer to the argv vector that we are hunting around the * target process space for, and converting to addresses in * our address space (kd->argspc). */ ap = np = kd->argspc; argv = kd->argv; len = 0; /* * Loop over pages, filling in the argument vector. * Note that the argv strings could be pointing *anywhere* in * the user address space and are no longer contiguous. * Note that *argv is modified when we are going to fetch a string * that crosses a page boundary. We copy the next part of the string * into to "np" and eventually convert the pointer. */ while (argv < kd->argv + narg && *argv != 0) { /* get the address that the current argv string is on */ addr = (u_long)*argv & ~(PAGE_SIZE - 1); /* is it the same page as the last one? */ if (addr != oaddr) { if (kvm_uread(kd, pid, addr, kd->argbuf, PAGE_SIZE) != PAGE_SIZE) return (0); oaddr = addr; } /* offset within the page... kd->argbuf */ addr = (u_long)*argv & (PAGE_SIZE - 1); /* cp = start of string, cc = count of chars in this chunk */ cp = kd->argbuf + addr; cc = PAGE_SIZE - addr; /* dont get more than asked for by user process */ if (maxcnt > 0 && cc > maxcnt - len) cc = maxcnt - len; /* pointer to end of string if we found it in this page */ ep = memchr(cp, '\0', cc); if (ep != 0) cc = ep - cp + 1; /* * at this point, cc is the count of the chars that we are * going to retrieve this time. we may or may not have found * the end of it. (ep points to the null if the end is known) */ /* will we exceed the malloc/realloced buffer? */ if (len + cc > kd->arglen) { int off; char **pp; char *op = kd->argspc; kd->arglen *= 2; kd->argspc = (char *)_kvm_realloc(kd, kd->argspc, kd->arglen); if (kd->argspc == 0) return (0); /* * Adjust argv pointers in case realloc moved * the string space. */ off = kd->argspc - op; for (pp = kd->argv; pp < argv; pp++) *pp += off; ap += off; np += off; } /* np = where to put the next part of the string in kd->argspc*/ /* np is kinda redundant.. could use "kd->argspc + len" */ memcpy(np, cp, cc); np += cc; /* inc counters */ len += cc; /* * if end of string found, set the *argv pointer to the * saved beginning of string, and advance. argv points to * somewhere in kd->argv.. This is initially relative * to the target process, but when we close it off, we set * it to point in our address space. */ if (ep != 0) { *argv++ = ap; ap = np; } else { /* update the address relative to the target process */ *argv += cc; } if (maxcnt > 0 && len >= maxcnt) { /* * We're stopping prematurely. Terminate the * current string. */ if (ep == 0) { *np = '\0'; *argv++ = ap; } break; } } /* Make sure argv is terminated. */ *argv = 0; return (kd->argv); } static void ps_str_a(struct ps_strings *p, u_long *addr, int *n) { *addr = (u_long)p->ps_argvstr; *n = p->ps_nargvstr; } static void ps_str_e(struct ps_strings *p, u_long *addr, int *n) { *addr = (u_long)p->ps_envstr; *n = p->ps_nenvstr; } /* * Determine if the proc indicated by p is still active. * This test is not 100% foolproof in theory, but chances of * being wrong are very low. */ static int proc_verify(kvm_t *kd, const struct kinfo_proc *p) { struct kinfo_proc kp; int mib[4]; size_t len; int error; mib[0] = CTL_KERN; mib[1] = KERN_PROC; mib[2] = KERN_PROC_PID; mib[3] = p->kp_pid; len = sizeof(kp); error = sysctl(mib, 4, &kp, &len, NULL, 0); if (error) return (0); error = (p->kp_pid == kp.kp_pid && (kp.kp_stat != SZOMB || p->kp_stat == SZOMB)); return (error); } static char ** kvm_doargv(kvm_t *kd, const struct kinfo_proc *kp, int nchr, void (*info)(struct ps_strings *, u_long *, int *)) { char **ap; u_long addr; int cnt; static struct ps_strings arginfo; static u_long ps_strings; size_t len; if (ps_strings == 0) { len = sizeof(ps_strings); if (sysctlbyname("kern.ps_strings", &ps_strings, &len, NULL, 0) == -1) ps_strings = PS_STRINGS; } /* * Pointers are stored at the top of the user stack. */ if (kp->kp_stat == SZOMB || kvm_uread(kd, kp->kp_pid, ps_strings, (char *)&arginfo, sizeof(arginfo)) != sizeof(arginfo)) return (0); (*info)(&arginfo, &addr, &cnt); if (cnt == 0) return (0); ap = kvm_argv(kd, kp->kp_pid, addr, cnt, nchr); /* * For live kernels, make sure this process didn't go away. */ if (ap != 0 && (kvm_ishost(kd) || kvm_isvkernel(kd)) && !proc_verify(kd, kp)) ap = 0; return (ap); } /* * Get the command args. This code is now machine independent. */ char ** kvm_getargv(kvm_t *kd, const struct kinfo_proc *kp, int nchr) { int oid[4]; int i; size_t bufsz; static unsigned long buflen; static char *buf, *p; static char **bufp; static int argc; if (!kvm_ishost(kd)) { /* XXX: vkernels */ _kvm_err(kd, kd->program, "cannot read user space from dead kernel"); return (0); } if (!buflen) { bufsz = sizeof(buflen); i = sysctlbyname("kern.ps_arg_cache_limit", &buflen, &bufsz, NULL, 0); if (i == -1) { buflen = 0; } else { buf = malloc(buflen); if (buf == NULL) buflen = 0; argc = 32; bufp = malloc(sizeof(char *) * argc); } } if (buf != NULL) { oid[0] = CTL_KERN; oid[1] = KERN_PROC; oid[2] = KERN_PROC_ARGS; oid[3] = kp->kp_pid; bufsz = buflen; i = sysctl(oid, 4, buf, &bufsz, 0, 0); if (i == 0 && bufsz > 0) { i = 0; p = buf; do { bufp[i++] = p; p += strlen(p) + 1; if (i >= argc) { argc += argc; bufp = realloc(bufp, sizeof(char *) * argc); } } while (p < buf + bufsz); bufp[i++] = 0; return (bufp); } } if (kp->kp_flags & P_SYSTEM) return (NULL); return (kvm_doargv(kd, kp, nchr, ps_str_a)); } char ** kvm_getenvv(kvm_t *kd, const struct kinfo_proc *kp, int nchr) { return (kvm_doargv(kd, kp, nchr, ps_str_e)); } /* * Read from user space. The user context is given by pid. */ ssize_t kvm_uread(kvm_t *kd, pid_t pid, u_long uva, char *buf, size_t len) { char *cp; char procfile[MAXPATHLEN]; ssize_t amount; int fd; if (!kvm_ishost(kd)) { /* XXX: vkernels */ _kvm_err(kd, kd->program, "cannot read user space from dead kernel"); return (0); } sprintf(procfile, "/proc/%d/mem", pid); fd = open(procfile, O_RDONLY, 0); if (fd < 0) { _kvm_err(kd, kd->program, "cannot open %s", procfile); close(fd); return (0); } cp = buf; while (len > 0) { errno = 0; if (lseek(fd, (off_t)uva, 0) == -1 && errno != 0) { _kvm_err(kd, kd->program, "invalid address (%lx) in %s", uva, procfile); break; } amount = read(fd, cp, len); if (amount < 0) { _kvm_syserr(kd, kd->program, "error reading %s", procfile); break; } if (amount == 0) { _kvm_err(kd, kd->program, "EOF reading %s", procfile); break; } cp += amount; uva += amount; len -= amount; } close(fd); return ((ssize_t)(cp - buf)); }