[SRU][M][PATCH 3/4] netfilter: nft_set_pipapo: remove scratch_aligned pointer
Bethany Jamison
bethany.jamison at canonical.com
Fri Apr 12 18:49:58 UTC 2024
From: Florian Westphal <fw at strlen.de>
use ->scratch for both avx2 and the generic implementation.
After previous change the scratch->map member is always aligned properly
for AVX2, so we can just use scratch->map in AVX2 too.
The alignoff delta is stored in the scratchpad so we can reconstruct
the correct address to free the area again.
Fixes: 7400b063969b ("nft_set_pipapo: Introduce AVX2-based lookup implementation")
Reviewed-by: Stefano Brivio <sbrivio at redhat.com>
Signed-off-by: Florian Westphal <fw at strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo at netfilter.org>
(cherry picked from commit 5a8cdf6fd860ac5e6d08d72edbcecee049a7fec4)
CVE-2024-25809
Signed-off-by: Bethany Jamison <bethany.jamison at canonical.com>
---
net/netfilter/nft_set_pipapo.c | 41 +++++------------------------
net/netfilter/nft_set_pipapo.h | 6 ++---
net/netfilter/nft_set_pipapo_avx2.c | 2 +-
3 files changed, 10 insertions(+), 39 deletions(-)
diff --git a/net/netfilter/nft_set_pipapo.c b/net/netfilter/nft_set_pipapo.c
index b6bca59b7ba66..8e9b200779666 100644
--- a/net/netfilter/nft_set_pipapo.c
+++ b/net/netfilter/nft_set_pipapo.c
@@ -1116,6 +1116,7 @@ static void pipapo_free_scratch(const struct nft_pipapo_match *m, unsigned int c
return;
mem = s;
+ mem -= s->align_off;
kfree(mem);
}
@@ -1135,6 +1136,7 @@ static int pipapo_realloc_scratch(struct nft_pipapo_match *clone,
struct nft_pipapo_scratch *scratch;
#ifdef NFT_PIPAPO_ALIGN
void *scratch_aligned;
+ u32 align_off;
#endif
scratch = kzalloc_node(struct_size(scratch, map,
bsize_max * 2) +
@@ -1153,8 +1155,6 @@ static int pipapo_realloc_scratch(struct nft_pipapo_match *clone,
pipapo_free_scratch(clone, i);
- *per_cpu_ptr(clone->scratch, i) = scratch;
-
#ifdef NFT_PIPAPO_ALIGN
/* Align &scratch->map (not the struct itself): the extra
* %NFT_PIPAPO_ALIGN_HEADROOM bytes passed to kzalloc_node()
@@ -1166,8 +1166,12 @@ static int pipapo_realloc_scratch(struct nft_pipapo_match *clone,
scratch_aligned = NFT_PIPAPO_LT_ALIGN(&scratch->map);
scratch_aligned -= offsetof(struct nft_pipapo_scratch, map);
- *per_cpu_ptr(clone->scratch_aligned, i) = scratch_aligned;
+ align_off = scratch_aligned - (void *)scratch;
+
+ scratch = scratch_aligned;
+ scratch->align_off = align_off;
#endif
+ *per_cpu_ptr(clone->scratch, i) = scratch;
}
return 0;
@@ -1320,11 +1324,6 @@ static struct nft_pipapo_match *pipapo_clone(struct nft_pipapo_match *old)
if (!new->scratch)
goto out_scratch;
-#ifdef NFT_PIPAPO_ALIGN
- new->scratch_aligned = alloc_percpu(*new->scratch_aligned);
- if (!new->scratch_aligned)
- goto out_scratch;
-#endif
for_each_possible_cpu(i)
*per_cpu_ptr(new->scratch, i) = NULL;
@@ -1377,9 +1376,6 @@ static struct nft_pipapo_match *pipapo_clone(struct nft_pipapo_match *old)
out_scratch_realloc:
for_each_possible_cpu(i)
pipapo_free_scratch(new, i);
-#ifdef NFT_PIPAPO_ALIGN
- free_percpu(new->scratch_aligned);
-#endif
out_scratch:
free_percpu(new->scratch);
kfree(new);
@@ -1666,11 +1662,7 @@ static void pipapo_free_match(struct nft_pipapo_match *m)
for_each_possible_cpu(i)
pipapo_free_scratch(m, i);
-#ifdef NFT_PIPAPO_ALIGN
- free_percpu(m->scratch_aligned);
-#endif
free_percpu(m->scratch);
-
pipapo_free_fields(m);
kfree(m);
@@ -2165,16 +2157,6 @@ static int nft_pipapo_init(const struct nft_set *set,
for_each_possible_cpu(i)
*per_cpu_ptr(m->scratch, i) = NULL;
-#ifdef NFT_PIPAPO_ALIGN
- m->scratch_aligned = alloc_percpu(struct nft_pipapo_scratch *);
- if (!m->scratch_aligned) {
- err = -ENOMEM;
- goto out_free;
- }
- for_each_possible_cpu(i)
- *per_cpu_ptr(m->scratch_aligned, i) = NULL;
-#endif
-
rcu_head_init(&m->rcu);
nft_pipapo_for_each_field(f, i, m) {
@@ -2205,9 +2187,6 @@ static int nft_pipapo_init(const struct nft_set *set,
return 0;
out_free:
-#ifdef NFT_PIPAPO_ALIGN
- free_percpu(m->scratch_aligned);
-#endif
free_percpu(m->scratch);
out_scratch:
kfree(m);
@@ -2261,9 +2240,6 @@ static void nft_pipapo_destroy(const struct nft_ctx *ctx,
nft_set_pipapo_match_destroy(ctx, set, m);
-#ifdef NFT_PIPAPO_ALIGN
- free_percpu(m->scratch_aligned);
-#endif
for_each_possible_cpu(cpu)
pipapo_free_scratch(m, cpu);
free_percpu(m->scratch);
@@ -2278,9 +2254,6 @@ static void nft_pipapo_destroy(const struct nft_ctx *ctx,
if (priv->dirty)
nft_set_pipapo_match_destroy(ctx, set, m);
-#ifdef NFT_PIPAPO_ALIGN
- free_percpu(priv->clone->scratch_aligned);
-#endif
for_each_possible_cpu(cpu)
pipapo_free_scratch(priv->clone, cpu);
free_percpu(priv->clone->scratch);
diff --git a/net/netfilter/nft_set_pipapo.h b/net/netfilter/nft_set_pipapo.h
index de96e1a01dc0b..30a3d092cd841 100644
--- a/net/netfilter/nft_set_pipapo.h
+++ b/net/netfilter/nft_set_pipapo.h
@@ -133,10 +133,12 @@ struct nft_pipapo_field {
/**
* struct nft_pipapo_scratch - percpu data used for lookup and matching
* @map_index: Current working bitmap index, toggled between field matches
+ * @align_off: Offset to get the originally allocated address
* @map: store partial matching results during lookup
*/
struct nft_pipapo_scratch {
u8 map_index;
+ u32 align_off;
unsigned long map[];
};
@@ -144,16 +146,12 @@ struct nft_pipapo_scratch {
* struct nft_pipapo_match - Data used for lookup and matching
* @field_count Amount of fields in set
* @scratch: Preallocated per-CPU maps for partial matching results
- * @scratch_aligned: Version of @scratch aligned to NFT_PIPAPO_ALIGN bytes
* @bsize_max: Maximum lookup table bucket size of all fields, in longs
* @rcu Matching data is swapped on commits
* @f: Fields, with lookup and mapping tables
*/
struct nft_pipapo_match {
int field_count;
-#ifdef NFT_PIPAPO_ALIGN
- struct nft_pipapo_scratch * __percpu *scratch_aligned;
-#endif
struct nft_pipapo_scratch * __percpu *scratch;
size_t bsize_max;
struct rcu_head rcu;
diff --git a/net/netfilter/nft_set_pipapo_avx2.c b/net/netfilter/nft_set_pipapo_avx2.c
index 78213c73af2e2..90e275bb3e5d7 100644
--- a/net/netfilter/nft_set_pipapo_avx2.c
+++ b/net/netfilter/nft_set_pipapo_avx2.c
@@ -1139,7 +1139,7 @@ bool nft_pipapo_avx2_lookup(const struct net *net, const struct nft_set *set,
*/
kernel_fpu_begin_mask(0);
- scratch = *raw_cpu_ptr(m->scratch_aligned);
+ scratch = *raw_cpu_ptr(m->scratch);
if (unlikely(!scratch)) {
kernel_fpu_end();
return false;
--
2.34.1
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