diff mbox series

[net-next,07/12] netfilter: nft_set_pipapo: do not rely on ZERO_SIZE_PTR

Message ID 20240221112637.5396-8-fw@strlen.de (mailing list archive)
State Accepted
Commit 07ace0bbe03b3d8e85869af1dec5e4087b1d57b8
Delegated to: Netdev Maintainers
Headers show
Series [net-next,01/12] netfilter: expect: Simplify the allocation of slab caches in nf_conntrack_expect_init | expand

Checks

Context Check Description
netdev/series_format success Pull request is its own cover letter
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 940 this patch: 940
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 3 maintainers not CCed: pablo@netfilter.org coreteam@netfilter.org kadlec@netfilter.org
netdev/build_clang success Errors and warnings before: 957 this patch: 957
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 No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 957 this patch: 957
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 29 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-2024-02-23--03-00 (tests: 1457)

Commit Message

Florian Westphal Feb. 21, 2024, 11:26 a.m. UTC 
pipapo relies on kmalloc(0) returning ZERO_SIZE_PTR (i.e., not NULL
but pointer is invalid).

Rework this to not call slab allocator when we'd request a 0-byte
allocation.

Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
---
 net/netfilter/nft_set_pipapo.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/net/netfilter/nft_set_pipapo.c b/net/netfilter/nft_set_pipapo.c
index dedb17a4e07c..625c06b8bc39 100644
--- a/net/netfilter/nft_set_pipapo.c
+++ b/net/netfilter/nft_set_pipapo.c
@@ -525,6 +525,8 @@  static struct nft_pipapo_elem *pipapo_get(const struct net *net,
 	int i;
 
 	m = priv->clone;
+	if (m->bsize_max == 0)
+		return ret;
 
 	res_map = kmalloc_array(m->bsize_max, sizeof(*res_map), GFP_ATOMIC);
 	if (!res_map) {
@@ -1367,11 +1369,17 @@  static struct nft_pipapo_match *pipapo_clone(struct nft_pipapo_match *old)
 		       src->bsize * sizeof(*dst->lt) *
 		       src->groups * NFT_PIPAPO_BUCKETS(src->bb));
 
-		dst->mt = kvmalloc(src->rules * sizeof(*src->mt), GFP_KERNEL);
-		if (!dst->mt)
-			goto out_mt;
+		if (src->rules > 0) {
+			dst->mt = kvmalloc_array(src->rules, sizeof(*src->mt),
+						 GFP_KERNEL);
+			if (!dst->mt)
+				goto out_mt;
+
+			memcpy(dst->mt, src->mt, src->rules * sizeof(*src->mt));
+		} else {
+			dst->mt = NULL;
+		}
 
-		memcpy(dst->mt, src->mt, src->rules * sizeof(*src->mt));
 		src++;
 		dst++;
 	}