Using retain for fields longer than 32 bits is not supported.
Do not allow user to do it.
Signed-off-by: Amir Vadai <a...@vadai.me>
---
man/man8/tc-pedit.8 | 3 ++-
tc/m_pedit.c | 6 ++++++
2 files changed, 8 insertions(+), 1 deletion(-)
diff --git a/man/man8/tc-pedit.8 b/man/man8/tc-pedit.8
index 7f482eafc6c7..9c4d57b972cc 100644
--- a/man/man8/tc-pedit.8
+++ b/man/man8/tc-pedit.8
@@ -266,7 +266,8 @@ Keep the addressed data as is.
.BI retain " RVAL"
This optional extra part of
.I CMD_SPEC
-allows to exclude bits from being changed.
+allows to exclude bits from being changed. Supported only for 32 bits fields
+or smaller.
.TP
.I CONTROL
The following keywords allow to control how the tree of qdisc, classes,
diff --git a/tc/m_pedit.c b/tc/m_pedit.c
index 7ef2acc52bce..9b74c965932e 100644
--- a/tc/m_pedit.c
+++ b/tc/m_pedit.c
@@ -353,6 +353,12 @@ int parse_cmd(int *argc_p, char ***argv_p, __u32 len, int
type, __u32 retain,
argv++;
}
+ if (len > 4 && retain != ~0) {
+ fprintf(stderr,
+ "retain is not supported for fields longer the 32
bits\n");
+ return -1;
+ }
+
if (type == TMAC) {
res = pack_mac(sel, tkey, (__u8 *)val);
goto done;
--
2.12.2
