diff mbox series

[net,06/14] netfilter: nft_payload: report ERANGE for too long offset and length

Message ID 20220824220330.64283-7-pablo@netfilter.org (mailing list archive)
State Accepted
Commit 94254f990c07e9ddf1634e0b727fab821c3b5bf9
Delegated to: Netdev Maintainers
Headers show
Series [net,01/14] netfilter: ebtables: reject blobs that don't provide all entry points | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net
netdev/fixes_present success Fixes tag present in non-next series
netdev/subject_prefix success Link
netdev/cover_letter success Pull request is its own cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 86 this patch: 86
netdev/cc_maintainers fail 1 blamed authors not CCed: kaber@trash.net; 4 maintainers not CCed: fw@strlen.de kaber@trash.net coreteam@netfilter.org kadlec@netfilter.org
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 86 this patch: 86
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 22 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Pablo Neira Ayuso Aug. 24, 2022, 10:03 p.m. UTC 
Instead of offset and length are truncation to u8, report ERANGE.

Fixes: 96518518cc41 ("netfilter: add nftables")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nft_payload.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c
index 2e7ac007cb30..4fee67abfe2c 100644
--- a/net/netfilter/nft_payload.c
+++ b/net/netfilter/nft_payload.c
@@ -833,6 +833,7 @@  nft_payload_select_ops(const struct nft_ctx *ctx,
 {
 	enum nft_payload_bases base;
 	unsigned int offset, len;
+	int err;
 
 	if (tb[NFTA_PAYLOAD_BASE] == NULL ||
 	    tb[NFTA_PAYLOAD_OFFSET] == NULL ||
@@ -859,8 +860,13 @@  nft_payload_select_ops(const struct nft_ctx *ctx,
 	if (tb[NFTA_PAYLOAD_DREG] == NULL)
 		return ERR_PTR(-EINVAL);
 
-	offset = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_OFFSET]));
-	len    = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_LEN]));
+	err = nft_parse_u32_check(tb[NFTA_PAYLOAD_OFFSET], U8_MAX, &offset);
+	if (err < 0)
+		return ERR_PTR(err);
+
+	err = nft_parse_u32_check(tb[NFTA_PAYLOAD_LEN], U8_MAX, &len);
+	if (err < 0)
+		return ERR_PTR(err);
 
 	if (len <= 4 && is_power_of_2(len) && IS_ALIGNED(offset, len) &&
 	    base != NFT_PAYLOAD_LL_HEADER && base != NFT_PAYLOAD_INNER_HEADER)