Another round, this time obvious sizes which are in immediate scope of the free() call, e.g. right below the malloc() call.
This leaves only a few selected free() calls with size zero in if_spppsubr.c due to the fact that there is currently no variable to keep track of username and password string lengths. Feedback? OK? Index: if_spppsubr.c =================================================================== RCS file: /cvs/src/sys/net/if_spppsubr.c,v retrieving revision 1.185 diff -u -p -r1.185 if_spppsubr.c --- if_spppsubr.c 14 Aug 2020 12:17:34 -0000 1.185 +++ if_spppsubr.c 22 Aug 2020 12:25:37 -0000 @@ -1737,7 +1737,7 @@ sppp_lcp_RCR(struct sppp *sp, struct lcp len -= 4; origlen = len; - buf = r = malloc (len, M_TEMP, M_NOWAIT); + buf = r = malloc (origlen, M_TEMP, M_NOWAIT); if (! buf) return (0); @@ -1749,7 +1749,7 @@ sppp_lcp_RCR(struct sppp *sp, struct lcp p = (void*) (h+1); for (rlen = 0; len > 1; len -= p[1], p += p[1]) { if (p[1] < 2 || p[1] > len) { - free(buf, M_TEMP, 0); + free(buf, M_TEMP, origlen); return (-1); } if (debug) @@ -1926,7 +1926,7 @@ sppp_lcp_RCR(struct sppp *sp, struct lcp } end: - free(buf, M_TEMP, 0); + free(buf, M_TEMP, origlen); return (rlen == 0); } @@ -2312,7 +2312,7 @@ sppp_ipcp_RCR(struct sppp *sp, struct lc { u_char *buf, *r, *p; struct ifnet *ifp = &sp->pp_if; - int rlen, origlen, debug = ifp->if_flags & IFF_DEBUG; + int rlen, origlen, buflen, debug = ifp->if_flags & IFF_DEBUG; u_int32_t hisaddr, desiredaddr; len -= 4; @@ -2321,7 +2321,8 @@ sppp_ipcp_RCR(struct sppp *sp, struct lc * Make sure to allocate a buf that can at least hold a * conf-nak with an `address' option. We might need it below. */ - buf = r = malloc ((len < 6? 6: len), M_TEMP, M_NOWAIT); + buflen = len < 6? 6: len; + buf = r = malloc (buflen, M_TEMP, M_NOWAIT); if (! buf) return (0); @@ -2332,7 +2333,7 @@ sppp_ipcp_RCR(struct sppp *sp, struct lc p = (void*) (h+1); for (rlen = 0; len > 1; len -= p[1], p += p[1]) { if (p[1] < 2 || p[1] > len) { - free(buf, M_TEMP, 0); + free(buf, M_TEMP, buflen); return (-1); } if (debug) @@ -2476,7 +2477,7 @@ sppp_ipcp_RCR(struct sppp *sp, struct lc } end: - free(buf, M_TEMP, 0); + free(buf, M_TEMP, buflen); return (rlen == 0); } @@ -2773,7 +2774,7 @@ sppp_ipv6cp_RCR(struct sppp *sp, struct { u_char *buf, *r, *p; struct ifnet *ifp = &sp->pp_if; - int rlen, origlen, debug = ifp->if_flags & IFF_DEBUG; + int rlen, origlen, buflen, debug = ifp->if_flags & IFF_DEBUG; struct in6_addr myaddr, desiredaddr, suggestaddr; int ifidcount; int type; @@ -2786,7 +2787,8 @@ sppp_ipv6cp_RCR(struct sppp *sp, struct * Make sure to allocate a buf that can at least hold a * conf-nak with an `address' option. We might need it below. */ - buf = r = malloc ((len < 6? 6: len), M_TEMP, M_NOWAIT); + buflen = len < 6? 6: len; + buf = r = malloc (buflen, M_TEMP, M_NOWAIT); if (! buf) return (0); @@ -2799,7 +2801,7 @@ sppp_ipv6cp_RCR(struct sppp *sp, struct for (rlen=0; len>1 && p[1]; len-=p[1], p+=p[1]) { /* Sanity check option length */ if (p[1] < 2 || p[1] > len) { - free(buf, M_TEMP, 0); + free(buf, M_TEMP, buflen); return (-1); } if (debug) @@ -2933,7 +2935,7 @@ sppp_ipv6cp_RCR(struct sppp *sp, struct } end: - free(buf, M_TEMP, 0); + free(buf, M_TEMP, buflen); return (rlen == 0); } @@ -4475,10 +4477,10 @@ sppp_get_params(struct sppp *sp, struct spr->phase = sp->pp_phase; if (copyout(spr, (caddr_t)ifr->ifr_data, sizeof(*spr)) != 0) { - free(spr, M_DEVBUF, 0); + free(spr, M_DEVBUF, sizeof(*spr)); return EFAULT; } - free(spr, M_DEVBUF, 0); + free(spr, M_DEVBUF, sizeof(*spr)); break; } case SPPPIOGMAUTH: @@ -4498,10 +4500,10 @@ sppp_get_params(struct sppp *sp, struct strlcpy(spa->name, auth->name, sizeof(spa->name)); if (copyout(spa, (caddr_t)ifr->ifr_data, sizeof(*spa)) != 0) { - free(spa, M_DEVBUF, 0); + free(spa, M_DEVBUF, sizeof(*spa)); return EFAULT; } - free(spa, M_DEVBUF, 0); + free(spa, M_DEVBUF, sizeof(*spa)); break; } default: @@ -4528,7 +4530,7 @@ sppp_set_params(struct sppp *sp, struct spr = malloc(sizeof(*spr), M_DEVBUF, M_WAITOK); if (copyin((caddr_t)ifr->ifr_data, spr, sizeof(*spr)) != 0) { - free(spr, M_DEVBUF, 0); + free(spr, M_DEVBUF, sizeof(*spr)); return EFAULT; } /* @@ -4537,7 +4539,7 @@ sppp_set_params(struct sppp *sp, struct * * XXX Should allow to set or clear pp_flags. */ - free(spr, M_DEVBUF, 0); + free(spr, M_DEVBUF, sizeof(*spr)); break; } case SPPPIOSMAUTH: @@ -4564,13 +4566,13 @@ sppp_set_params(struct sppp *sp, struct auth = (cmd == SPPPIOSMAUTH) ? &sp->myauth : &sp->hisauth; if (copyin((caddr_t)ifr->ifr_data, spa, sizeof(*spa)) != 0) { - free(spa, M_DEVBUF, 0); + free(spa, M_DEVBUF, sizeof(*spa)); return EFAULT; } if (spa->proto != 0 && spa->proto != PPP_PAP && spa->proto != PPP_CHAP) { - free(spa, M_DEVBUF, 0); + free(spa, M_DEVBUF, sizeof(*spa)); return EINVAL; } @@ -4592,7 +4594,7 @@ sppp_set_params(struct sppp *sp, struct p = malloc(len, M_DEVBUF, M_WAITOK); strlcpy(p, spa->name, len); if (auth->name != NULL) - free(auth->name, M_DEVBUF, 0); + free(auth->name, M_DEVBUF, len); auth->name = p; if (spa->secret[0] != '\0') { @@ -4601,7 +4603,7 @@ sppp_set_params(struct sppp *sp, struct p = malloc(len, M_DEVBUF, M_WAITOK); strlcpy(p, spa->secret, len); if (auth->secret != NULL) - free(auth->secret, M_DEVBUF, 0); + free(auth->secret, M_DEVBUF, len); auth->secret = p; } else if (!auth->secret) { p = malloc(1, M_DEVBUF, M_WAITOK); @@ -4609,7 +4611,7 @@ sppp_set_params(struct sppp *sp, struct auth->secret = p; } } - free(spa, M_DEVBUF, 0); + free(spa, M_DEVBUF, sizeof(*spa)); break; } default: