From 732d35fd08058a678327ec908528fcc9514c9e48 Mon Sep 17 00:00:00 2001 From: Thomas Graf Date: Thu, 5 Jul 2012 14:19:56 +0200 Subject: [PATCH] can: gw: Use nla_policy to validate netlink attributes Also use nla_get_u32() instead of nla_memcpy() to access u32 attribtues. Signed-off-by: Thomas Graf Tested-by: Oliver Hartkopp Acked-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- net/can/gw.c | 47 +++++++++++++++++++++++------------------------ 1 file changed, 23 insertions(+), 24 deletions(-) diff --git a/net/can/gw.c b/net/can/gw.c index a3ff980a1754..a1c639c730a3 100644 --- a/net/can/gw.c +++ b/net/can/gw.c @@ -558,6 +558,18 @@ cont: return skb->len; } +static const struct nla_policy cgw_policy[CGW_MAX+1] = { + [CGW_MOD_AND] = { .len = sizeof(struct cgw_frame_mod) }, + [CGW_MOD_OR] = { .len = sizeof(struct cgw_frame_mod) }, + [CGW_MOD_XOR] = { .len = sizeof(struct cgw_frame_mod) }, + [CGW_MOD_SET] = { .len = sizeof(struct cgw_frame_mod) }, + [CGW_CS_XOR] = { .len = sizeof(struct cgw_csum_xor) }, + [CGW_CS_CRC8] = { .len = sizeof(struct cgw_csum_crc8) }, + [CGW_SRC_IF] = { .type = NLA_U32 }, + [CGW_DST_IF] = { .type = NLA_U32 }, + [CGW_FILTER] = { .len = sizeof(struct can_filter) }, +}; + /* check for common and gwtype specific attributes */ static int cgw_parse_attr(struct nlmsghdr *nlh, struct cf_mod *mod, u8 gwtype, void *gwtypeattr) @@ -570,14 +582,14 @@ static int cgw_parse_attr(struct nlmsghdr *nlh, struct cf_mod *mod, /* initialize modification & checksum data space */ memset(mod, 0, sizeof(*mod)); - err = nlmsg_parse(nlh, sizeof(struct rtcanmsg), tb, CGW_MAX, NULL); + err = nlmsg_parse(nlh, sizeof(struct rtcanmsg), tb, CGW_MAX, + cgw_policy); if (err < 0) return err; /* check for AND/OR/XOR/SET modifications */ - if (tb[CGW_MOD_AND] && - nla_len(tb[CGW_MOD_AND]) == CGW_MODATTR_LEN) { + if (tb[CGW_MOD_AND]) { nla_memcpy(&mb, tb[CGW_MOD_AND], CGW_MODATTR_LEN); canframecpy(&mod->modframe.and, &mb.cf); @@ -593,8 +605,7 @@ static int cgw_parse_attr(struct nlmsghdr *nlh, struct cf_mod *mod, mod->modfunc[modidx++] = mod_and_data; } - if (tb[CGW_MOD_OR] && - nla_len(tb[CGW_MOD_OR]) == CGW_MODATTR_LEN) { + if (tb[CGW_MOD_OR]) { nla_memcpy(&mb, tb[CGW_MOD_OR], CGW_MODATTR_LEN); canframecpy(&mod->modframe.or, &mb.cf); @@ -610,8 +621,7 @@ static int cgw_parse_attr(struct nlmsghdr *nlh, struct cf_mod *mod, mod->modfunc[modidx++] = mod_or_data; } - if (tb[CGW_MOD_XOR] && - nla_len(tb[CGW_MOD_XOR]) == CGW_MODATTR_LEN) { + if (tb[CGW_MOD_XOR]) { nla_memcpy(&mb, tb[CGW_MOD_XOR], CGW_MODATTR_LEN); canframecpy(&mod->modframe.xor, &mb.cf); @@ -627,8 +637,7 @@ static int cgw_parse_attr(struct nlmsghdr *nlh, struct cf_mod *mod, mod->modfunc[modidx++] = mod_xor_data; } - if (tb[CGW_MOD_SET] && - nla_len(tb[CGW_MOD_SET]) == CGW_MODATTR_LEN) { + if (tb[CGW_MOD_SET]) { nla_memcpy(&mb, tb[CGW_MOD_SET], CGW_MODATTR_LEN); canframecpy(&mod->modframe.set, &mb.cf); @@ -647,9 +656,7 @@ static int cgw_parse_attr(struct nlmsghdr *nlh, struct cf_mod *mod, /* check for checksum operations after CAN frame modifications */ if (modidx) { - if (tb[CGW_CS_CRC8] && - nla_len(tb[CGW_CS_CRC8]) == CGW_CS_CRC8_LEN) { - + if (tb[CGW_CS_CRC8]) { struct cgw_csum_crc8 *c = (struct cgw_csum_crc8 *)\ nla_data(tb[CGW_CS_CRC8]); @@ -674,9 +681,7 @@ static int cgw_parse_attr(struct nlmsghdr *nlh, struct cf_mod *mod, mod->csumfunc.crc8 = cgw_csum_crc8_neg; } - if (tb[CGW_CS_XOR] && - nla_len(tb[CGW_CS_XOR]) == CGW_CS_XOR_LEN) { - + if (tb[CGW_CS_XOR]) { struct cgw_csum_xor *c = (struct cgw_csum_xor *)\ nla_data(tb[CGW_CS_XOR]); @@ -710,8 +715,7 @@ static int cgw_parse_attr(struct nlmsghdr *nlh, struct cf_mod *mod, memset(ccgw, 0, sizeof(*ccgw)); /* check for can_filter in attributes */ - if (tb[CGW_FILTER] && - nla_len(tb[CGW_FILTER]) == sizeof(struct can_filter)) + if (tb[CGW_FILTER]) nla_memcpy(&ccgw->filter, tb[CGW_FILTER], sizeof(struct can_filter)); @@ -721,13 +725,8 @@ static int cgw_parse_attr(struct nlmsghdr *nlh, struct cf_mod *mod, if (!tb[CGW_SRC_IF] || !tb[CGW_DST_IF]) return err; - if (nla_len(tb[CGW_SRC_IF]) == sizeof(u32)) - nla_memcpy(&ccgw->src_idx, tb[CGW_SRC_IF], - sizeof(u32)); - - if (nla_len(tb[CGW_DST_IF]) == sizeof(u32)) - nla_memcpy(&ccgw->dst_idx, tb[CGW_DST_IF], - sizeof(u32)); + ccgw->src_idx = nla_get_u32(tb[CGW_SRC_IF]); + ccgw->dst_idx = nla_get_u32(tb[CGW_DST_IF]); /* both indices set to 0 for flushing all routing entries */ if (!ccgw->src_idx && !ccgw->dst_idx)