Index: stable/11/lib/libkvm/kvm.c =================================================================== --- stable/11/lib/libkvm/kvm.c (revision 316070) +++ stable/11/lib/libkvm/kvm.c (revision 316071) @@ -1,945 +1,950 @@ /*- * 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. * 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. */ #include __FBSDID("$FreeBSD$"); #if defined(LIBC_SCCS) && !defined(lint) #if 0 static char sccsid[] = "@(#)kvm.c 8.2 (Berkeley) 2/13/94"; #endif #endif /* LIBC_SCCS and not lint */ #include #include #define _WANT_VNET #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "kvm_private.h" SET_DECLARE(kvm_arch, struct kvm_arch); +static char _kd_is_null[] = ""; + /* from src/lib/libc/gen/nlist.c */ int __fdnlist(int, struct nlist *); static int kvm_fdnlist(kvm_t *kd, struct kvm_nlist *list) { kvaddr_t addr; int error, nfail; if (kd->resolve_symbol == NULL) { struct nlist *nl; int count, i; for (count = 0; list[count].n_name != NULL && list[count].n_name[0] != '\0'; count++) ; nl = calloc(count + 1, sizeof(*nl)); for (i = 0; i < count; i++) nl[i].n_name = list[i].n_name; nfail = __fdnlist(kd->nlfd, nl); for (i = 0; i < count; i++) { list[i].n_type = nl[i].n_type; list[i].n_value = nl[i].n_value; } free(nl); return (nfail); } nfail = 0; while (list->n_name != NULL && list->n_name[0] != '\0') { error = kd->resolve_symbol(list->n_name, &addr); if (error != 0) { nfail++; list->n_value = 0; list->n_type = 0; } else { list->n_value = addr; list->n_type = N_DATA | N_EXT; } list++; } return (nfail); } char * kvm_geterr(kvm_t *kd) { + + if (kd == NULL) + return (_kd_is_null); return (kd->errbuf); } #include /* * Report an error using printf style arguments. "program" is kd->program * on hard errors, and 0 on soft errors, so that under sun error emulation, * only hard errors are printed out (otherwise, programs like gdb will * generate tons of error messages when trying to access bogus pointers). */ void _kvm_err(kvm_t *kd, const char *program, const char *fmt, ...) { va_list ap; va_start(ap, fmt); if (program != NULL) { (void)fprintf(stderr, "%s: ", program); (void)vfprintf(stderr, fmt, ap); (void)fputc('\n', stderr); } else (void)vsnprintf(kd->errbuf, sizeof(kd->errbuf), fmt, ap); va_end(ap); } void _kvm_syserr(kvm_t *kd, const char *program, const char *fmt, ...) { va_list ap; int n; va_start(ap, fmt); if (program != NULL) { (void)fprintf(stderr, "%s: ", program); (void)vfprintf(stderr, fmt, ap); (void)fprintf(stderr, ": %s\n", strerror(errno)); } else { char *cp = kd->errbuf; (void)vsnprintf(cp, sizeof(kd->errbuf), fmt, ap); n = strlen(cp); (void)snprintf(&cp[n], sizeof(kd->errbuf) - n, ": %s", strerror(errno)); } va_end(ap); } void * _kvm_malloc(kvm_t *kd, size_t n) { void *p; if ((p = calloc(n, sizeof(char))) == NULL) _kvm_err(kd, kd->program, "can't allocate %zu bytes: %s", n, strerror(errno)); return (p); } static int _kvm_read_kernel_ehdr(kvm_t *kd) { Elf *elf; if (elf_version(EV_CURRENT) == EV_NONE) { _kvm_err(kd, kd->program, "Unsupported libelf"); return (-1); } elf = elf_begin(kd->nlfd, ELF_C_READ, NULL); if (elf == NULL) { _kvm_err(kd, kd->program, "%s", elf_errmsg(0)); return (-1); } if (elf_kind(elf) != ELF_K_ELF) { _kvm_err(kd, kd->program, "kernel is not an ELF file"); return (-1); } if (gelf_getehdr(elf, &kd->nlehdr) == NULL) { _kvm_err(kd, kd->program, "%s", elf_errmsg(0)); elf_end(elf); return (-1); } elf_end(elf); switch (kd->nlehdr.e_ident[EI_DATA]) { case ELFDATA2LSB: case ELFDATA2MSB: return (0); default: _kvm_err(kd, kd->program, "unsupported ELF data encoding for kernel"); return (-1); } } int _kvm_probe_elf_kernel(kvm_t *kd, int class, int machine) { return (kd->nlehdr.e_ident[EI_CLASS] == class && kd->nlehdr.e_type == ET_EXEC && kd->nlehdr.e_machine == machine); } int _kvm_is_minidump(kvm_t *kd) { char minihdr[8]; if (kd->rawdump) return (0); if (pread(kd->pmfd, &minihdr, 8, 0) == 8 && memcmp(&minihdr, "minidump", 8) == 0) return (1); return (0); } /* * The powerpc backend has a hack to strip a leading kerneldump * header from the core before treating it as an ELF header. * * We can add that here if we can get a change to libelf to support * an initial offset into the file. Alternatively we could patch * savecore to extract cores from a regular file instead. */ int _kvm_read_core_phdrs(kvm_t *kd, size_t *phnump, GElf_Phdr **phdrp) { GElf_Ehdr ehdr; GElf_Phdr *phdr; Elf *elf; size_t i, phnum; elf = elf_begin(kd->pmfd, ELF_C_READ, NULL); if (elf == NULL) { _kvm_err(kd, kd->program, "%s", elf_errmsg(0)); return (-1); } if (elf_kind(elf) != ELF_K_ELF) { _kvm_err(kd, kd->program, "invalid core"); goto bad; } if (gelf_getclass(elf) != kd->nlehdr.e_ident[EI_CLASS]) { _kvm_err(kd, kd->program, "invalid core"); goto bad; } if (gelf_getehdr(elf, &ehdr) == NULL) { _kvm_err(kd, kd->program, "%s", elf_errmsg(0)); goto bad; } if (ehdr.e_type != ET_CORE) { _kvm_err(kd, kd->program, "invalid core"); goto bad; } if (ehdr.e_machine != kd->nlehdr.e_machine) { _kvm_err(kd, kd->program, "invalid core"); goto bad; } if (elf_getphdrnum(elf, &phnum) == -1) { _kvm_err(kd, kd->program, "%s", elf_errmsg(0)); goto bad; } phdr = calloc(phnum, sizeof(*phdr)); if (phdr == NULL) { _kvm_err(kd, kd->program, "failed to allocate phdrs"); goto bad; } for (i = 0; i < phnum; i++) { if (gelf_getphdr(elf, i, &phdr[i]) == NULL) { _kvm_err(kd, kd->program, "%s", elf_errmsg(0)); goto bad; } } elf_end(elf); *phnump = phnum; *phdrp = phdr; return (0); bad: elf_end(elf); return (-1); } static void _kvm_hpt_insert(struct hpt *hpt, uint64_t pa, off_t off) { struct hpte *hpte; uint32_t fnv = FNV1_32_INIT; fnv = fnv_32_buf(&pa, sizeof(pa), fnv); fnv &= (HPT_SIZE - 1); hpte = malloc(sizeof(*hpte)); hpte->pa = pa; hpte->off = off; hpte->next = hpt->hpt_head[fnv]; hpt->hpt_head[fnv] = hpte; } void _kvm_hpt_init(kvm_t *kd, struct hpt *hpt, void *base, size_t len, off_t off, int page_size, int word_size) { uint64_t bits, idx, pa; uint64_t *base64; uint32_t *base32; base64 = base; base32 = base; for (idx = 0; idx < len / word_size; idx++) { if (word_size == sizeof(uint64_t)) bits = _kvm64toh(kd, base64[idx]); else bits = _kvm32toh(kd, base32[idx]); pa = idx * word_size * NBBY * page_size; for (; bits != 0; bits >>= 1, pa += page_size) { if ((bits & 1) == 0) continue; _kvm_hpt_insert(hpt, pa, off); off += page_size; } } } off_t _kvm_hpt_find(struct hpt *hpt, uint64_t pa) { struct hpte *hpte; uint32_t fnv = FNV1_32_INIT; fnv = fnv_32_buf(&pa, sizeof(pa), fnv); fnv &= (HPT_SIZE - 1); for (hpte = hpt->hpt_head[fnv]; hpte != NULL; hpte = hpte->next) { if (pa == hpte->pa) return (hpte->off); } return (-1); } void _kvm_hpt_free(struct hpt *hpt) { struct hpte *hpte, *next; int i; for (i = 0; i < HPT_SIZE; i++) { for (hpte = hpt->hpt_head[i]; hpte != NULL; hpte = next) { next = hpte->next; free(hpte); } } } static kvm_t * _kvm_open(kvm_t *kd, const char *uf, const char *mf, int flag, char *errout) { struct kvm_arch **parch; struct stat st; kd->vmfd = -1; kd->pmfd = -1; kd->nlfd = -1; kd->vmst = NULL; kd->procbase = NULL; kd->argspc = NULL; kd->argv = NULL; if (uf == NULL) uf = getbootfile(); else if (strlen(uf) >= MAXPATHLEN) { _kvm_err(kd, kd->program, "exec file name too long"); goto failed; } if (flag & ~O_RDWR) { _kvm_err(kd, kd->program, "bad flags arg"); goto failed; } if (mf == NULL) mf = _PATH_MEM; if ((kd->pmfd = open(mf, flag | O_CLOEXEC, 0)) < 0) { _kvm_syserr(kd, kd->program, "%s", mf); goto failed; } if (fstat(kd->pmfd, &st) < 0) { _kvm_syserr(kd, kd->program, "%s", mf); goto failed; } if (S_ISREG(st.st_mode) && st.st_size <= 0) { errno = EINVAL; _kvm_syserr(kd, kd->program, "empty file"); goto failed; } if (S_ISCHR(st.st_mode)) { /* * If this is a character special device, then check that * it's /dev/mem. If so, open kmem too. (Maybe we should * make it work for either /dev/mem or /dev/kmem -- in either * case you're working with a live kernel.) */ if (strcmp(mf, _PATH_DEVNULL) == 0) { kd->vmfd = open(_PATH_DEVNULL, O_RDONLY | O_CLOEXEC); return (kd); } else if (strcmp(mf, _PATH_MEM) == 0) { if ((kd->vmfd = open(_PATH_KMEM, flag | O_CLOEXEC)) < 0) { _kvm_syserr(kd, kd->program, "%s", _PATH_KMEM); goto failed; } return (kd); } } /* * This is either a crash dump or a remote live system with its physical * memory fully accessible via a special device. * Open the namelist fd and determine the architecture. */ if ((kd->nlfd = open(uf, O_RDONLY | O_CLOEXEC, 0)) < 0) { _kvm_syserr(kd, kd->program, "%s", uf); goto failed; } if (_kvm_read_kernel_ehdr(kd) < 0) goto failed; if (strncmp(mf, _PATH_FWMEM, strlen(_PATH_FWMEM)) == 0 || strncmp(mf, _PATH_DEVVMM, strlen(_PATH_DEVVMM)) == 0) { kd->rawdump = 1; kd->writable = 1; } SET_FOREACH(parch, kvm_arch) { if ((*parch)->ka_probe(kd)) { kd->arch = *parch; break; } } if (kd->arch == NULL) { _kvm_err(kd, kd->program, "unsupported architecture"); goto failed; } /* * Non-native kernels require a symbol resolver. */ if (!kd->arch->ka_native(kd) && kd->resolve_symbol == NULL) { _kvm_err(kd, kd->program, "non-native kernel requires a symbol resolver"); goto failed; } /* * Initialize the virtual address translation machinery. */ if (kd->arch->ka_initvtop(kd) < 0) goto failed; return (kd); failed: /* * Copy out the error if doing sane error semantics. */ if (errout != NULL) strlcpy(errout, kd->errbuf, _POSIX2_LINE_MAX); (void)kvm_close(kd); return (NULL); } kvm_t * kvm_openfiles(const char *uf, const char *mf, const char *sf __unused, int flag, char *errout) { kvm_t *kd; if ((kd = calloc(1, sizeof(*kd))) == NULL) { if (errout != NULL) (void)strlcpy(errout, strerror(errno), _POSIX2_LINE_MAX); return (NULL); } return (_kvm_open(kd, uf, mf, flag, errout)); } kvm_t * kvm_open(const char *uf, const char *mf, const char *sf __unused, int flag, const char *errstr) { kvm_t *kd; if ((kd = calloc(1, sizeof(*kd))) == NULL) { if (errstr != NULL) (void)fprintf(stderr, "%s: %s\n", errstr, strerror(errno)); return (NULL); } kd->program = errstr; return (_kvm_open(kd, uf, mf, flag, NULL)); } kvm_t * kvm_open2(const char *uf, const char *mf, int flag, char *errout, int (*resolver)(const char *, kvaddr_t *)) { kvm_t *kd; if ((kd = calloc(1, sizeof(*kd))) == NULL) { if (errout != NULL) (void)strlcpy(errout, strerror(errno), _POSIX2_LINE_MAX); return (NULL); } kd->resolve_symbol = resolver; return (_kvm_open(kd, uf, mf, flag, errout)); } int kvm_close(kvm_t *kd) { int error = 0; if (kd == NULL) { errno = EINVAL; return (-1); } if (kd->vmst != NULL) kd->arch->ka_freevtop(kd); if (kd->pmfd >= 0) error |= close(kd->pmfd); if (kd->vmfd >= 0) error |= close(kd->vmfd); if (kd->nlfd >= 0) error |= close(kd->nlfd); if (kd->procbase != 0) free((void *)kd->procbase); if (kd->argbuf != 0) free((void *) kd->argbuf); if (kd->argspc != 0) free((void *) kd->argspc); if (kd->argv != 0) free((void *)kd->argv); free((void *)kd); return (error); } /* * Walk the list of unresolved symbols, generate a new list and prefix the * symbol names, try again, and merge back what we could resolve. */ static int kvm_fdnlist_prefix(kvm_t *kd, struct kvm_nlist *nl, int missing, const char *prefix, kvaddr_t (*validate_fn)(kvm_t *, kvaddr_t)) { struct kvm_nlist *n, *np, *p; char *cp, *ce; const char *ccp; size_t len; int slen, unresolved; /* * Calculate the space we need to malloc for nlist and names. * We are going to store the name twice for later lookups: once * with the prefix and once the unmodified name delmited by \0. */ len = 0; unresolved = 0; for (p = nl; p->n_name && p->n_name[0]; ++p) { if (p->n_type != N_UNDF) continue; len += sizeof(struct kvm_nlist) + strlen(prefix) + 2 * (strlen(p->n_name) + 1); unresolved++; } if (unresolved == 0) return (unresolved); /* Add space for the terminating nlist entry. */ len += sizeof(struct kvm_nlist); unresolved++; /* Alloc one chunk for (nlist, [names]) and setup pointers. */ n = np = malloc(len); bzero(n, len); if (n == NULL) return (missing); cp = ce = (char *)np; cp += unresolved * sizeof(struct kvm_nlist); ce += len; /* Generate shortened nlist with special prefix. */ unresolved = 0; for (p = nl; p->n_name && p->n_name[0]; ++p) { if (p->n_type != N_UNDF) continue; *np = *p; /* Save the new\0orig. name so we can later match it again. */ slen = snprintf(cp, ce - cp, "%s%s%c%s", prefix, (prefix[0] != '\0' && p->n_name[0] == '_') ? (p->n_name + 1) : p->n_name, '\0', p->n_name); if (slen < 0 || slen >= ce - cp) continue; np->n_name = cp; cp += slen + 1; np++; unresolved++; } /* Do lookup on the reduced list. */ np = n; unresolved = kvm_fdnlist(kd, np); /* Check if we could resolve further symbols and update the list. */ if (unresolved >= 0 && unresolved < missing) { /* Find the first freshly resolved entry. */ for (; np->n_name && np->n_name[0]; np++) if (np->n_type != N_UNDF) break; /* * The lists are both in the same order, * so we can walk them in parallel. */ for (p = nl; np->n_name && np->n_name[0] && p->n_name && p->n_name[0]; ++p) { if (p->n_type != N_UNDF) continue; /* Skip expanded name and compare to orig. one. */ ccp = np->n_name + strlen(np->n_name) + 1; if (strcmp(ccp, p->n_name) != 0) continue; /* Update nlist with new, translated results. */ p->n_type = np->n_type; if (validate_fn) p->n_value = (*validate_fn)(kd, np->n_value); else p->n_value = np->n_value; missing--; /* Find next freshly resolved entry. */ for (np++; np->n_name && np->n_name[0]; np++) if (np->n_type != N_UNDF) break; } } /* We could assert missing = unresolved here. */ free(n); return (unresolved); } int _kvm_nlist(kvm_t *kd, struct kvm_nlist *nl, int initialize) { struct kvm_nlist *p; int nvalid; struct kld_sym_lookup lookup; int error; const char *prefix = ""; char symname[1024]; /* XXX-BZ symbol name length limit? */ int tried_vnet, tried_dpcpu; /* * If we can't use the kld symbol lookup, revert to the * slow library call. */ if (!ISALIVE(kd)) { error = kvm_fdnlist(kd, nl); if (error <= 0) /* Hard error or success. */ return (error); if (_kvm_vnet_initialized(kd, initialize)) error = kvm_fdnlist_prefix(kd, nl, error, VNET_SYMPREFIX, _kvm_vnet_validaddr); if (error > 0 && _kvm_dpcpu_initialized(kd, initialize)) error = kvm_fdnlist_prefix(kd, nl, error, DPCPU_SYMPREFIX, _kvm_dpcpu_validaddr); return (error); } /* * We can use the kld lookup syscall. Go through each nlist entry * and look it up with a kldsym(2) syscall. */ nvalid = 0; tried_vnet = 0; tried_dpcpu = 0; again: for (p = nl; p->n_name && p->n_name[0]; ++p) { if (p->n_type != N_UNDF) continue; lookup.version = sizeof(lookup); lookup.symvalue = 0; lookup.symsize = 0; error = snprintf(symname, sizeof(symname), "%s%s", prefix, (prefix[0] != '\0' && p->n_name[0] == '_') ? (p->n_name + 1) : p->n_name); if (error < 0 || error >= (int)sizeof(symname)) continue; lookup.symname = symname; if (lookup.symname[0] == '_') lookup.symname++; if (kldsym(0, KLDSYM_LOOKUP, &lookup) != -1) { p->n_type = N_TEXT; if (_kvm_vnet_initialized(kd, initialize) && strcmp(prefix, VNET_SYMPREFIX) == 0) p->n_value = _kvm_vnet_validaddr(kd, lookup.symvalue); else if (_kvm_dpcpu_initialized(kd, initialize) && strcmp(prefix, DPCPU_SYMPREFIX) == 0) p->n_value = _kvm_dpcpu_validaddr(kd, lookup.symvalue); else p->n_value = lookup.symvalue; ++nvalid; /* lookup.symsize */ } } /* * Check the number of entries that weren't found. If they exist, * try again with a prefix for virtualized or DPCPU symbol names. */ error = ((p - nl) - nvalid); if (error && _kvm_vnet_initialized(kd, initialize) && !tried_vnet) { tried_vnet = 1; prefix = VNET_SYMPREFIX; goto again; } if (error && _kvm_dpcpu_initialized(kd, initialize) && !tried_dpcpu) { tried_dpcpu = 1; prefix = DPCPU_SYMPREFIX; goto again; } /* * Return the number of entries that weren't found. If they exist, * also fill internal error buffer. */ error = ((p - nl) - nvalid); if (error) _kvm_syserr(kd, kd->program, "kvm_nlist"); return (error); } int kvm_nlist2(kvm_t *kd, struct kvm_nlist *nl) { /* * If called via the public interface, permit initialization of * further virtualized modules on demand. */ return (_kvm_nlist(kd, nl, 1)); } int kvm_nlist(kvm_t *kd, struct nlist *nl) { struct kvm_nlist *kl; int count, i, nfail; /* * Avoid reporting truncated addresses by failing for non-native * cores. */ if (!kvm_native(kd)) { _kvm_err(kd, kd->program, "kvm_nlist of non-native vmcore"); return (-1); } for (count = 0; nl[count].n_name != NULL && nl[count].n_name[0] != '\0'; count++) ; if (count == 0) return (0); kl = calloc(count + 1, sizeof(*kl)); for (i = 0; i < count; i++) kl[i].n_name = nl[i].n_name; nfail = kvm_nlist2(kd, kl); for (i = 0; i < count; i++) { nl[i].n_type = kl[i].n_type; nl[i].n_other = 0; nl[i].n_desc = 0; nl[i].n_value = kl[i].n_value; } return (nfail); } ssize_t kvm_read(kvm_t *kd, u_long kva, void *buf, size_t len) { return (kvm_read2(kd, kva, buf, len)); } ssize_t kvm_read2(kvm_t *kd, kvaddr_t kva, void *buf, size_t len) { int cc; ssize_t cr; off_t pa; char *cp; if (ISALIVE(kd)) { /* * We're using /dev/kmem. Just read straight from the * device and let the active kernel do the address translation. */ errno = 0; if (lseek(kd->vmfd, (off_t)kva, 0) == -1 && errno != 0) { _kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)kva); return (-1); } cr = read(kd->vmfd, buf, len); if (cr < 0) { _kvm_syserr(kd, 0, "kvm_read"); return (-1); } else if (cr < (ssize_t)len) _kvm_err(kd, kd->program, "short read"); return (cr); } cp = buf; while (len > 0) { cc = kd->arch->ka_kvatop(kd, kva, &pa); if (cc == 0) return (-1); if (cc > (ssize_t)len) cc = len; errno = 0; if (lseek(kd->pmfd, pa, 0) == -1 && errno != 0) { _kvm_syserr(kd, 0, _PATH_MEM); break; } cr = read(kd->pmfd, cp, cc); if (cr < 0) { _kvm_syserr(kd, kd->program, "kvm_read"); break; } /* * If ka_kvatop returns a bogus value or our core file is * truncated, we might wind up seeking beyond the end of the * core file in which case the read will return 0 (EOF). */ if (cr == 0) break; cp += cr; kva += cr; len -= cr; } return (cp - (char *)buf); } ssize_t kvm_write(kvm_t *kd, u_long kva, const void *buf, size_t len) { int cc; ssize_t cw; off_t pa; const char *cp; if (!ISALIVE(kd) && !kd->writable) { _kvm_err(kd, kd->program, "kvm_write not implemented for dead kernels"); return (-1); } if (ISALIVE(kd)) { /* * Just like kvm_read, only we write. */ errno = 0; if (lseek(kd->vmfd, (off_t)kva, 0) == -1 && errno != 0) { _kvm_err(kd, 0, "invalid address (%lx)", kva); return (-1); } cc = write(kd->vmfd, buf, len); if (cc < 0) { _kvm_syserr(kd, 0, "kvm_write"); return (-1); } else if ((size_t)cc < len) _kvm_err(kd, kd->program, "short write"); return (cc); } cp = buf; while (len > 0) { cc = kd->arch->ka_kvatop(kd, kva, &pa); if (cc == 0) return (-1); if (cc > (ssize_t)len) cc = len; errno = 0; if (lseek(kd->pmfd, pa, 0) == -1 && errno != 0) { _kvm_syserr(kd, 0, _PATH_MEM); break; } cw = write(kd->pmfd, cp, cc); if (cw < 0) { _kvm_syserr(kd, kd->program, "kvm_write"); break; } /* * If ka_kvatop returns a bogus value or our core file is * truncated, we might wind up seeking beyond the end of the * core file in which case the read will return 0 (EOF). */ if (cw == 0) break; cp += cw; kva += cw; len -= cw; } - return (cp - (char *)buf); + return (cp - (const char *)buf); } int kvm_native(kvm_t *kd) { if (ISALIVE(kd)) return (1); return (kd->arch->ka_native(kd)); } Index: stable/11/lib/libkvm/kvm_geterr.3 =================================================================== --- stable/11/lib/libkvm/kvm_geterr.3 (revision 316070) +++ stable/11/lib/libkvm/kvm_geterr.3 (revision 316071) @@ -1,78 +1,87 @@ .\" Copyright (c) 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. .\" 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. .\" .\" @(#)kvm_geterr.3 8.1 (Berkeley) 6/4/93 .\" $FreeBSD$ .\" -.Dd June 4, 1993 +.Dd March 21, 2017 .Dt KVM_GETERR 3 .Os .Sh NAME .Nm kvm_geterr .Nd get error message on kvm descriptor .Sh LIBRARY .Lb libkvm .Sh SYNOPSIS .In kvm.h .Ft char * .Fn kvm_geterr "kvm_t *kd" .Sh DESCRIPTION This function returns a string describing the most recent error condition on the descriptor .Fa kd . The results are undefined if the most recent .Xr kvm 3 library call did not produce an error. The string returned is stored in memory owned by .Xr kvm 3 so the message should be copied out and saved elsewhere if necessary. +.Sh RETURN VALUES +The function +.Fn kvm_geterr +will return "" if +.Fa kd +is +.Dv NULL +or an error has not been captured for +.Fa kd . .Sh SEE ALSO .Xr kvm 3 , .Xr kvm_close 3 , .Xr kvm_getargv 3 , .Xr kvm_getenvv 3 , .Xr kvm_getprocs 3 , .Xr kvm_nlist 3 , .Xr kvm_open 3 , .Xr kvm_openfiles 3 , .Xr kvm_read 3 , .Xr kvm_write 3 .Sh BUGS This routine cannot be used to access error conditions due to a failed .Fn kvm_openfiles call, since failure is indicated by returning a .Dv NULL descriptor. Therefore, errors on open are output to the special error buffer passed to .Fn kvm_openfiles . This option is not available to .Fn kvm_open . Index: stable/11 =================================================================== --- stable/11 (revision 316070) +++ stable/11 (revision 316071) Property changes on: stable/11 ___________________________________________________________________ Modified: svn:mergeinfo ## -0,0 +0,1 ## Merged /head:r315686,315688