[PATCH iproute2] utils: bump max args number to 256 for batch files
From: Guillaume Nault <hidden>
Date: 2021-06-01 17:09:40
Subsystem:
library code, the rest · Maintainers:
Andrew Morton, Linus Torvalds
Large tc filters can have many arguments. For example the following
filter matches the first 7 MPLS LSEs, pops all of them, then updates
the Ethernet header and redirects the resulting packet to eth1.
filter add dev eth0 ingress handle 44 priority 100 \
protocol mpls_uc flower mpls \
lse depth 1 label 1040076 tc 4 bos 0 ttl 175 \
lse depth 2 label 89648 tc 2 bos 0 ttl 9 \
lse depth 3 label 63417 tc 5 bos 0 ttl 185 \
lse depth 4 label 593135 tc 5 bos 0 ttl 67 \
lse depth 5 label 857021 tc 0 bos 0 ttl 181 \
lse depth 6 label 239239 tc 1 bos 0 ttl 254 \
lse depth 7 label 30 tc 7 bos 1 ttl 237 \
action mpls pop protocol mpls_uc pipe \
action mpls pop protocol mpls_uc pipe \
action mpls pop protocol mpls_uc pipe \
action mpls pop protocol mpls_uc pipe \
action mpls pop protocol mpls_uc pipe \
action mpls pop protocol mpls_uc pipe \
action mpls pop protocol ipv6 pipe \
action vlan pop_eth pipe \
action vlan push_eth \
dst_mac 00:00:5e:00:53:7e \
src_mac 00:00:5e:00:53:03 pipe \
action mirred egress redirect dev eth1
This filter has 149 arguments, so it can't be used with tc -batch
which is limited to a 100.
Let's bump the limit to the next power of 2. That should leave a lot of
room for big batch commands.
Signed-off-by: Guillaume Nault <redacted>
---
Note: I have no production use case for MPLS stacks with 7 LSEs at the
moment, but 7 is the maximum depth the flow dissector can handle,
and having the possibility to express such rules with tc -batch
would help testing the kernel API (writing scripts that generate
filters, without worrying about the 100 parameters limit).
lib/utils.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/lib/utils.c b/lib/utils.c
index 93ae0c55..d5496e45 100644
--- a/lib/utils.c
+++ b/lib/utils.c@@ -1714,10 +1714,10 @@ int do_batch(const char *name, bool force, cmdlineno = 0; while (getcmdline(&line, &len, stdin) != -1) { - char *largv[100]; + char *largv[256]; int largc; - largc = makeargs(line, largv, 100); + largc = makeargs(line, largv, 256); if (!largc) continue; /* blank line */
--
2.21.3