Correct two errors which cancel each other out: * Do not send twice the length of the actual provided by the user to the kernel * Do not dump half the length of the cookie provided by the kernel
As the cookie is now stored in the kernel at its correct length rather than double the that length cookies of up to the maximum size of 16 bytes may now be stored rather than a maximum of half that length. Output of dump is the same before and after this change, but the data stored in the kernel is now exactly the cookie rather than the cookie + as many trailing zeros. Before: # tc filter add dev eth0 protocol ip parent ffff: \ flower ip_proto udp action drop \ cookie 0123456789abcdef0123456789abcdef RTNETLINK answers: Invalid argument After: # tc filter add dev eth0 protocol ip parent ffff: \ flower ip_proto udp action drop \ cookie 0123456789abcdef0123456789abcdef # tc filter show dev eth0 ingress eth_type ipv4 ip_proto udp not_in_hw action order 1: gact action drop random type none pass val 0 index 1 ref 1 bind 1 installed 1 sec used 1 sec Action statistics: Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0) backlog 0b 0p requeues 0 cookie len 16 0123456789abcdef0123456789abcdef Fixes: fd8b3d2c1b9b ("actions: Add support for user cookies") Cc: Jamal Hadi Salim <j...@mojatatu.com> Signed-off-by: Simon Horman <simon.hor...@netronome.com> --- tc/m_action.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tc/m_action.c b/tc/m_action.c index 6ebe85e1cbe3..397e9c5d4a7b 100644 --- a/tc/m_action.c +++ b/tc/m_action.c @@ -242,7 +242,7 @@ done0: invarg("cookie must be a hex string\n", *argv); - act_ck_len = slen; + act_ck_len = slen / 2; argc--; argv++; } @@ -307,7 +307,7 @@ static int tc_print_one_action(FILE *f, struct rtattr *arg) print_tcstats2_attr(f, tb[TCA_ACT_STATS], "\t", NULL); if (tb[TCA_ACT_COOKIE]) { int strsz = RTA_PAYLOAD(tb[TCA_ACT_COOKIE]); - char b1[strsz+1]; + char b1[strsz * 2 + 1]; fprintf(f, "\n\tcookie len %d %s ", strsz, hexstring_n2a(RTA_DATA(tb[TCA_ACT_COOKIE]), -- 2.1.4