* [PATCH bpf-next 1/2] test_bpf: Refactor test_skb_segment() to allow testing skb_segment() on numerous different skbs
2019-08-29 12:13 [RFC PATCH bpf-next 0/2] test_bpf: Add an skb_segment test for a linear head_frag=0 skb whose gso_size was mangled Shmulik Ladkani
@ 2019-08-29 12:13 ` Shmulik Ladkani
2019-08-29 12:13 ` [RFC PATCH bpf-next 2/2] test_bpf: Introduce 'gso_linear_no_head_frag' skb_segment test Shmulik Ladkani
1 sibling, 0 replies; 3+ messages in thread
From: Shmulik Ladkani @ 2019-08-29 12:13 UTC (permalink / raw)
To: Daniel Borkmann, Yonghong Song
Cc: Eric Dumazet, Alexei Starovoitov, netdev, bpf, Shmulik Ladkani
Currently, test_skb_segment() builds a single test skb and runs
skb_segment() on it.
Extend test_skb_segment() so it processes an array of numerous
skb/feature pairs to test.
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
---
lib/test_bpf.c | 51 ++++++++++++++++++++++++++++++++++++++++----------
1 file changed, 41 insertions(+), 10 deletions(-)
diff --git a/lib/test_bpf.c b/lib/test_bpf.c
index c41705835cba..5e80cb3d3ca0 100644
--- a/lib/test_bpf.c
+++ b/lib/test_bpf.c
@@ -6859,34 +6859,65 @@ static __init struct sk_buff *build_test_skb(void)
return NULL;
}
-static __init int test_skb_segment(void)
-{
+struct skb_segment_test {
+ const char *descr;
+ struct sk_buff *(*build_skb)(void);
netdev_features_t features;
+};
+
+static struct skb_segment_test skb_segment_tests[] __initconst = {
+ {
+ .descr = "gso_with_rx_frags",
+ .build_skb = build_test_skb,
+ .features = NETIF_F_SG | NETIF_F_GSO_PARTIAL | NETIF_F_IP_CSUM |
+ NETIF_F_IPV6_CSUM | NETIF_F_RXCSUM
+ }
+};
+
+static __init int test_skb_segment_single(const struct skb_segment_test *test)
+{
struct sk_buff *skb, *segs;
int ret = -1;
- features = NETIF_F_SG | NETIF_F_GSO_PARTIAL | NETIF_F_IP_CSUM |
- NETIF_F_IPV6_CSUM;
- features |= NETIF_F_RXCSUM;
- skb = build_test_skb();
+ skb = test->build_skb();
if (!skb) {
pr_info("%s: failed to build_test_skb", __func__);
goto done;
}
- segs = skb_segment(skb, features);
+ segs = skb_segment(skb, test->features);
if (!IS_ERR(segs)) {
kfree_skb_list(segs);
ret = 0;
- pr_info("%s: success in skb_segment!", __func__);
- } else {
- pr_info("%s: failed in skb_segment!", __func__);
}
kfree_skb(skb);
done:
return ret;
}
+static __init int test_skb_segment(void)
+{
+ int i, err_cnt = 0, pass_cnt = 0;
+
+ for (i = 0; i < ARRAY_SIZE(skb_segment_tests); i++) {
+ const struct skb_segment_test *test = &skb_segment_tests[i];
+
+ pr_info("#%d %s ", i, test->descr);
+
+ if (test_skb_segment_single(test)) {
+ pr_cont("FAIL\n");
+ err_cnt++;
+ } else {
+ pr_cont("PASS\n");
+ pass_cnt++;
+ }
+ }
+
+ pr_info("%s: Summary: %d PASSED, %d FAILED\n", __func__,
+ pass_cnt, err_cnt);
+ return err_cnt ? -EINVAL : 0;
+}
+
static __init int test_bpf(void)
{
int i, err_cnt = 0, pass_cnt = 0;
--
2.19.1
^ permalink raw reply related [flat|nested] 3+ messages in thread* [RFC PATCH bpf-next 2/2] test_bpf: Introduce 'gso_linear_no_head_frag' skb_segment test
2019-08-29 12:13 [RFC PATCH bpf-next 0/2] test_bpf: Add an skb_segment test for a linear head_frag=0 skb whose gso_size was mangled Shmulik Ladkani
2019-08-29 12:13 ` [PATCH bpf-next 1/2] test_bpf: Refactor test_skb_segment() to allow testing skb_segment() on numerous different skbs Shmulik Ladkani
@ 2019-08-29 12:13 ` Shmulik Ladkani
1 sibling, 0 replies; 3+ messages in thread
From: Shmulik Ladkani @ 2019-08-29 12:13 UTC (permalink / raw)
To: Daniel Borkmann, Yonghong Song
Cc: Eric Dumazet, Alexei Starovoitov, netdev, bpf, Shmulik Ladkani
Following reports of skb_segment() hitting a BUG_ON when working on
GROed skbs which have their gso_size mangled (e.g. after a
bpf_skb_change_proto call), add a reproducer test that mimics the
input skbs that lead to the mentioned BUG_ON as in [1].
[1] https://lists.openwall.net/netdev/2019/08/26/110
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
---
lib/test_bpf.c | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 63 insertions(+)
diff --git a/lib/test_bpf.c b/lib/test_bpf.c
index 5e80cb3d3ca0..2fe1e3ab3c89 100644
--- a/lib/test_bpf.c
+++ b/lib/test_bpf.c
@@ -6859,6 +6859,60 @@ static __init struct sk_buff *build_test_skb(void)
return NULL;
}
+static __init struct sk_buff *build_test_skb_linear_no_head_frag(void)
+{
+ unsigned int alloc_size = 2000;
+ unsigned int headroom = 102, doffset = 72, data_size = 1308;
+ struct sk_buff *skb[2];
+ int i;
+
+ /* skbs linked in a frag_list, both with linear data, with head_frag=0
+ * (data allocated by kmalloc), both have tcp data of 1308 bytes
+ * (total payload is 2616 bytes).
+ * Data offset is 72 bytes (40 ipv6 hdr, 32 tcp hdr). Some headroom.
+ */
+ for (i = 0; i < 2; i++) {
+ skb[i] = alloc_skb(alloc_size, GFP_KERNEL);
+ if (!skb[i]) {
+ if (i == 0)
+ goto err_skb0;
+ else
+ goto err_skb1;
+ }
+
+ skb[i]->protocol = htons(ETH_P_IPV6);
+ skb_reserve(skb[i], headroom);
+ skb_put(skb[i], doffset + data_size);
+ skb_reset_network_header(skb[i]);
+ if (i == 0)
+ skb_reset_mac_header(skb[i]);
+ else
+ skb_set_mac_header(skb[i], -ETH_HLEN);
+ __skb_pull(skb[i], doffset);
+ }
+
+ /* setup shinfo.
+ * mimic bpf_skb_proto_4_to_6, which resets gso_segs and assigns a
+ * reduced gso_size.
+ */
+ skb_shinfo(skb[0])->gso_size = 1288;
+ skb_shinfo(skb[0])->gso_type = SKB_GSO_TCPV6 | SKB_GSO_DODGY;
+ skb_shinfo(skb[0])->gso_segs = 0;
+ skb_shinfo(skb[0])->frag_list = skb[1];
+
+ /* adjust skb[0]'s len */
+ skb[0]->len += skb[1]->len;
+ skb[0]->data_len += skb[1]->len;
+ skb[0]->truesize += skb[1]->truesize;
+
+ return skb[0];
+
+err_skb1:
+ kfree_skb(skb[0]);
+err_skb0:
+ return NULL;
+}
+
struct skb_segment_test {
const char *descr;
struct sk_buff *(*build_skb)(void);
@@ -6871,6 +6925,15 @@ static struct skb_segment_test skb_segment_tests[] __initconst = {
.build_skb = build_test_skb,
.features = NETIF_F_SG | NETIF_F_GSO_PARTIAL | NETIF_F_IP_CSUM |
NETIF_F_IPV6_CSUM | NETIF_F_RXCSUM
+ },
+ {
+ .descr = "gso_linear_no_head_frag",
+ .build_skb = build_test_skb_linear_no_head_frag,
+ .features = NETIF_F_SG | NETIF_F_FRAGLIST |
+ NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_GSO |
+ NETIF_F_LLTX_BIT | NETIF_F_GRO |
+ NETIF_F_IPV6_CSUM | NETIF_F_RXCSUM |
+ NETIF_F_HW_VLAN_STAG_TX_BIT
}
};
--
2.19.1
^ permalink raw reply related [flat|nested] 3+ messages in thread