[233241.951068] BUG: using smp_processor_id() in preemptible [00000000] code: nginx/2725
[233241.951220] caller is nft_ng_random_eval+0x24/0x54 [nft_numgen]
[233241.951225] CPU: 2 PID: 2725 Comm: nginx Tainted: G OE 5.16.0-0.bpo.4-amd64 #1 Debian 5.16.12-1~bpo11+1
[233241.951227] Hardware name: Supermicro SYS-5039MC-H8TRF/X11SCD-F, BIOS 1.7 11/23/2021
[233241.951228] Call Trace:
[233241.951231] <TASK>
[233241.951233] dump_stack_lvl+0x48/0x5e
[233241.951236] check_preemption_disabled+0xde/0xe0
[233241.951239] nft_ng_random_eval+0x24/0x54 [nft_numgen]
Fixes: 978d8f9055c3 ("netfilter: nft_numgen: add map lookups for numgen random operations")
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
---
See https://bugzilla.netfilter.org/show_bug.cgi?id=1603
net/netfilter/nft_numgen.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/net/netfilter/nft_numgen.c b/net/netfilter/nft_numgen.c
index 81b40c663d86..78f860555c76 100644
--- a/net/netfilter/nft_numgen.c
+++ b/net/netfilter/nft_numgen.c
@@ -137,10 +137,15 @@ struct nft_ng_random {
static u32 nft_ng_random_gen(struct nft_ng_random *priv)
{
- struct rnd_state *state = this_cpu_ptr(&nft_numgen_prandom_state);
+ struct rnd_state *state;
+ u32 ret;
- return reciprocal_scale(prandom_u32_state(state), priv->modulus) +
- priv->offset;
+ preempt_disable();
+ state = this_cpu_ptr(&nft_numgen_prandom_state);
+ ret = reciprocal_scale(prandom_u32_state(state), priv->modulus) + priv->offset;
+ preempt_enable();
+
+ return ret;
}
static void nft_ng_random_eval(const struct nft_expr *expr,
--
2.30.2
