diff mbox series

[net,4/6] netfilter: nft_set_rbtree: skip sync GC for new elements in this transaction

Message ID 20230906162525.11079-5-fw@strlen.de (mailing list archive)
State Accepted
Commit 2ee52ae94baabf7ee09cf2a8d854b990dac5d0e4
Delegated to: Netdev Maintainers
Headers show
Series [net,1/6] netfilter: nftables: exthdr: fix 4-byte stack OOB write | 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/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: 1331 this patch: 1331
netdev/cc_maintainers warning 2 maintainers not CCed: kadlec@netfilter.org coreteam@netfilter.org
netdev/build_clang success Errors and warnings before: 1353 this patch: 1353
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: 1354 this patch: 1354
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 20 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Florian Westphal Sept. 6, 2023, 4:25 p.m. UTC 
From: Pablo Neira Ayuso <pablo@netfilter.org>

New elements in this transaction might expired before such transaction
ends. Skip sync GC for such elements otherwise commit path might walk
over an already released object. Once transaction is finished, async GC
will collect such expired element.

Fixes: f6c383b8c31a ("netfilter: nf_tables: adapt set backend to use GC transaction API")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
---
 net/netfilter/nft_set_rbtree.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/net/netfilter/nft_set_rbtree.c b/net/netfilter/nft_set_rbtree.c
index c6435e709231..f250b5399344 100644
--- a/net/netfilter/nft_set_rbtree.c
+++ b/net/netfilter/nft_set_rbtree.c
@@ -312,6 +312,7 @@  static int __nft_rbtree_insert(const struct net *net, const struct nft_set *set,
 	struct nft_rbtree_elem *rbe, *rbe_le = NULL, *rbe_ge = NULL;
 	struct rb_node *node, *next, *parent, **p, *first = NULL;
 	struct nft_rbtree *priv = nft_set_priv(set);
+	u8 cur_genmask = nft_genmask_cur(net);
 	u8 genmask = nft_genmask_next(net);
 	int d, err;
 
@@ -357,8 +358,11 @@  static int __nft_rbtree_insert(const struct net *net, const struct nft_set *set,
 		if (!nft_set_elem_active(&rbe->ext, genmask))
 			continue;
 
-		/* perform garbage collection to avoid bogus overlap reports. */
-		if (nft_set_elem_expired(&rbe->ext)) {
+		/* perform garbage collection to avoid bogus overlap reports
+		 * but skip new elements in this transaction.
+		 */
+		if (nft_set_elem_expired(&rbe->ext) &&
+		    nft_set_elem_active(&rbe->ext, cur_genmask)) {
 			err = nft_rbtree_gc_elem(set, priv, rbe, genmask);
 			if (err < 0)
 				return err;