From 6273ba66f26debbfe26f1424f2f44631ad709ecc Mon Sep 17 00:00:00 2001 From: Kristof Provost Date: Sun, 7 Jan 2018 13:35:15 +0000 Subject: [PATCH] pf: Avoid integer overflow issues by using mallocarray() iso. malloc() pfioctl() handles several ioctl that takes variable length input, these include: - DIOCRADDTABLES - DIOCRDELTABLES - DIOCRGETTABLES - DIOCRGETTSTATS - DIOCRCLRTSTATS - DIOCRSETTFLAGS All of them take a pfioc_table struct as input from userland. One of its elements (pfrio_size) is used in a buffer length calculation. The calculation contains an integer overflow which if triggered can lead to out of bound reads and writes later on. Reported by: Ilja Van Sprundel --- sys/netpfil/pf/pf_ioctl.c | 126 ++++++++++++++++++++++++++++++++------ 1 file changed, 108 insertions(+), 18 deletions(-) diff --git a/sys/netpfil/pf/pf_ioctl.c b/sys/netpfil/pf/pf_ioctl.c index 4a6fc0cd0de1..12b2ff6d2820 100644 --- a/sys/netpfil/pf/pf_ioctl.c +++ b/sys/netpfil/pf/pf_ioctl.c @@ -2531,7 +2531,12 @@ pfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td break; } totlen = io->pfrio_size * sizeof(struct pfr_table); - pfrts = malloc(totlen, M_TEMP, M_WAITOK); + pfrts = mallocarray(io->pfrio_size, sizeof(struct pfr_table), + M_TEMP, M_WAITOK); + if (! pfrts) { + error = ENOMEM; + break; + } error = copyin(io->pfrio_buffer, pfrts, totlen); if (error) { free(pfrts, M_TEMP); @@ -2555,7 +2560,12 @@ pfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td break; } totlen = io->pfrio_size * sizeof(struct pfr_table); - pfrts = malloc(totlen, M_TEMP, M_WAITOK); + pfrts = mallocarray(io->pfrio_size, sizeof(struct pfr_table), + M_TEMP, M_WAITOK); + if (! pfrts) { + error = ENOMEM; + break; + } error = copyin(io->pfrio_buffer, pfrts, totlen); if (error) { free(pfrts, M_TEMP); @@ -2579,7 +2589,12 @@ pfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td break; } totlen = io->pfrio_size * sizeof(struct pfr_table); - pfrts = malloc(totlen, M_TEMP, M_WAITOK); + pfrts = mallocarray(io->pfrio_size, sizeof(struct pfr_table), + M_TEMP, M_WAITOK); + if (! pfrts) { + error = ENOMEM; + break; + } PF_RULES_RLOCK(); error = pfr_get_tables(&io->pfrio_table, pfrts, &io->pfrio_size, io->pfrio_flags | PFR_FLAG_USERIOCTL); @@ -2600,7 +2615,12 @@ pfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td break; } totlen = io->pfrio_size * sizeof(struct pfr_tstats); - pfrtstats = malloc(totlen, M_TEMP, M_WAITOK); + pfrtstats = mallocarray(io->pfrio_size, + sizeof(struct pfr_tstats), M_TEMP, M_WAITOK); + if (! pfrtstats) { + error = ENOMEM; + break; + } PF_RULES_WLOCK(); error = pfr_get_tstats(&io->pfrio_table, pfrtstats, &io->pfrio_size, io->pfrio_flags | PFR_FLAG_USERIOCTL); @@ -2621,7 +2641,12 @@ pfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td break; } totlen = io->pfrio_size * sizeof(struct pfr_table); - pfrts = malloc(totlen, M_TEMP, M_WAITOK); + pfrts = mallocarray(io->pfrio_size, sizeof(struct pfr_table), + M_TEMP, M_WAITOK); + if (! pfrts) { + error = ENOMEM; + break; + } error = copyin(io->pfrio_buffer, pfrts, totlen); if (error) { free(pfrts, M_TEMP); @@ -2645,7 +2670,12 @@ pfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td break; } totlen = io->pfrio_size * sizeof(struct pfr_table); - pfrts = malloc(totlen, M_TEMP, M_WAITOK); + pfrts = mallocarray(io->pfrio_size, sizeof(struct pfr_table), + M_TEMP, M_WAITOK); + if (! pfrts) { + error = ENOMEM; + break; + } error = copyin(io->pfrio_buffer, pfrts, totlen); if (error) { free(pfrts, M_TEMP); @@ -2684,7 +2714,12 @@ pfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td break; } totlen = io->pfrio_size * sizeof(struct pfr_addr); - pfras = malloc(totlen, M_TEMP, M_WAITOK); + pfras = mallocarray(io->pfrio_size, sizeof(struct pfr_addr), + M_TEMP, M_WAITOK); + if (! pfras) { + error = ENOMEM; + break; + } error = copyin(io->pfrio_buffer, pfras, totlen); if (error) { free(pfras, M_TEMP); @@ -2711,7 +2746,12 @@ pfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td break; } totlen = io->pfrio_size * sizeof(struct pfr_addr); - pfras = malloc(totlen, M_TEMP, M_WAITOK); + pfras = mallocarray(io->pfrio_size, sizeof(struct pfr_addr), + M_TEMP, M_WAITOK); + if (! pfras) { + error = ENOMEM; + break; + } error = copyin(io->pfrio_buffer, pfras, totlen); if (error) { free(pfras, M_TEMP); @@ -2739,7 +2779,12 @@ pfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td } count = max(io->pfrio_size, io->pfrio_size2); totlen = count * sizeof(struct pfr_addr); - pfras = malloc(totlen, M_TEMP, M_WAITOK); + pfras = mallocarray(count, sizeof(struct pfr_addr), M_TEMP, + M_WAITOK); + if (! pfras) { + error = ENOMEM; + break; + } error = copyin(io->pfrio_buffer, pfras, totlen); if (error) { free(pfras, M_TEMP); @@ -2767,7 +2812,12 @@ pfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td break; } totlen = io->pfrio_size * sizeof(struct pfr_addr); - pfras = malloc(totlen, M_TEMP, M_WAITOK); + pfras = mallocarray(io->pfrio_size, sizeof(struct pfr_addr), + M_TEMP, M_WAITOK); + if (! pfras) { + error = ENOMEM; + break; + } PF_RULES_RLOCK(); error = pfr_get_addrs(&io->pfrio_table, pfras, &io->pfrio_size, io->pfrio_flags | PFR_FLAG_USERIOCTL); @@ -2788,7 +2838,12 @@ pfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td break; } totlen = io->pfrio_size * sizeof(struct pfr_astats); - pfrastats = malloc(totlen, M_TEMP, M_WAITOK); + pfrastats = mallocarray(io->pfrio_size, + sizeof(struct pfr_astats), M_TEMP, M_WAITOK); + if (! pfrastats) { + error = ENOMEM; + break; + } PF_RULES_RLOCK(); error = pfr_get_astats(&io->pfrio_table, pfrastats, &io->pfrio_size, io->pfrio_flags | PFR_FLAG_USERIOCTL); @@ -2809,7 +2864,12 @@ pfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td break; } totlen = io->pfrio_size * sizeof(struct pfr_addr); - pfras = malloc(totlen, M_TEMP, M_WAITOK); + pfras = mallocarray(io->pfrio_size, sizeof(struct pfr_addr), + M_TEMP, M_WAITOK); + if (! pfras) { + error = ENOMEM; + break; + } error = copyin(io->pfrio_buffer, pfras, totlen); if (error) { free(pfras, M_TEMP); @@ -2836,7 +2896,12 @@ pfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td break; } totlen = io->pfrio_size * sizeof(struct pfr_addr); - pfras = malloc(totlen, M_TEMP, M_WAITOK); + pfras = mallocarray(io->pfrio_size, sizeof(struct pfr_addr), + M_TEMP, M_WAITOK); + if (! pfras) { + error = ENOMEM; + break; + } error = copyin(io->pfrio_buffer, pfras, totlen); if (error) { free(pfras, M_TEMP); @@ -2863,7 +2928,12 @@ pfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td break; } totlen = io->pfrio_size * sizeof(struct pfr_addr); - pfras = malloc(totlen, M_TEMP, M_WAITOK); + pfras = mallocarray(io->pfrio_size, sizeof(struct pfr_addr), + M_TEMP, M_WAITOK); + if (! pfras) { + error = ENOMEM; + break; + } error = copyin(io->pfrio_buffer, pfras, totlen); if (error) { free(pfras, M_TEMP); @@ -2905,7 +2975,12 @@ pfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td break; } totlen = sizeof(struct pfioc_trans_e) * io->size; - ioes = malloc(totlen, M_TEMP, M_WAITOK); + ioes = mallocarray(io->size, sizeof(struct pfioc_trans_e), + M_TEMP, M_WAITOK); + if (! ioes) { + error = ENOMEM; + break; + } error = copyin(io->array, ioes, totlen); if (error) { free(ioes, M_TEMP); @@ -2971,7 +3046,12 @@ pfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td break; } totlen = sizeof(struct pfioc_trans_e) * io->size; - ioes = malloc(totlen, M_TEMP, M_WAITOK); + ioes = mallocarray(io->size, sizeof(struct pfioc_trans_e), + M_TEMP, M_WAITOK); + if (! ioes) { + error = ENOMEM; + break; + } error = copyin(io->array, ioes, totlen); if (error) { free(ioes, M_TEMP); @@ -3037,7 +3117,12 @@ pfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td break; } totlen = sizeof(struct pfioc_trans_e) * io->size; - ioes = malloc(totlen, M_TEMP, M_WAITOK); + ioes = mallocarray(io->size, sizeof(struct pfioc_trans_e), + M_TEMP, M_WAITOK); + if (! ioes) { + error = ENOMEM; + break; + } error = copyin(io->array, ioes, totlen); if (error) { free(ioes, M_TEMP); @@ -3238,7 +3323,12 @@ pfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td } bufsiz = io->pfiio_size * sizeof(struct pfi_kif); - ifstore = malloc(bufsiz, M_TEMP, M_WAITOK); + ifstore = mallocarray(io->pfiio_size, sizeof(struct pfi_kif), + M_TEMP, M_WAITOK); + if (! ifstore) { + error = ENOMEM; + break; + } PF_RULES_RLOCK(); pfi_get_ifaces(io->pfiio_name, ifstore, &io->pfiio_size); PF_RULES_RUNLOCK();