diff mbox series

[net,10/13] netfilter: nf_tables: do not allow mismatch field size and set key length

Message ID 20240118161726.14838-11-pablo@netfilter.org (mailing list archive)
State Accepted
Commit 3ce67e3793f48c1b9635beb9bb71116ca1e51b58
Delegated to: Netdev Maintainers
Headers show
Series [net,01/13] netfilter: nf_tables: reject invalid set policy | expand

Checks

Context Check Description
netdev/series_format success Pull request is its own cover letter
netdev/tree_selection success Clearly marked for net
netdev/ynl success SINGLE THREAD; Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag present in non-next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 1096 this patch: 1096
netdev/cc_maintainers success CCed 0 of 0 maintainers
netdev/build_clang success Errors and warnings before: 1095 this patch: 1095
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
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: 1111 this patch: 1111
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 19 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-01-18--21-00 (tests: 403)

Commit Message

Pablo Neira Ayuso Jan. 18, 2024, 4:17 p.m. UTC 
The set description provides the size of each field in the set whose sum
should not mismatch the set key length, bail out otherwise.

I did not manage to crash nft_set_pipapo with mismatch fields and set key
length so far, but this is UB which must be disallowed.

Fixes: f3a2181e16f1 ("netfilter: nf_tables: Support for sets with multiple ranged fields")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nf_tables_api.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 50b595ef6389..e9fa4a32c093 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -4813,8 +4813,8 @@  static int nft_set_desc_concat_parse(const struct nlattr *attr,
 static int nft_set_desc_concat(struct nft_set_desc *desc,
 			       const struct nlattr *nla)
 {
+	u32 num_regs = 0, key_num_regs = 0;
 	struct nlattr *attr;
-	u32 num_regs = 0;
 	int rem, err, i;
 
 	nla_for_each_nested(attr, nla, rem) {
@@ -4829,6 +4829,10 @@  static int nft_set_desc_concat(struct nft_set_desc *desc,
 	for (i = 0; i < desc->field_count; i++)
 		num_regs += DIV_ROUND_UP(desc->field_len[i], sizeof(u32));
 
+	key_num_regs = DIV_ROUND_UP(desc->klen, sizeof(u32));
+	if (key_num_regs != num_regs)
+		return -EINVAL;
+
 	if (num_regs > NFT_REG32_COUNT)
 		return -E2BIG;