diff mbox series

[net-next,v2,1/3] net: ipv6/addrconf: ensure that regen_advance is at least 2 seconds

Message ID 20240214062711.608363-2-alexhenrie24@gmail.com (mailing list archive)
State Accepted
Commit 2aa8f155b09519814e449dc19adacf01fd1367ee
Delegated to: Netdev Maintainers
Headers show
Series net: ipv6/addrconf: ensure that temporary addresses' preferred lifetimes are long enough | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 989 this patch: 989
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 2 maintainers not CCed: linux-doc@vger.kernel.org corbet@lwn.net
netdev/build_clang success Errors and warnings before: 1006 this patch: 1006
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 1006 this patch: 1006
netdev/checkpatch warning CHECK: spaces preferred around that '/' (ctx:VxV) WARNING: line length of 82 exceeds 80 columns WARNING: line length of 96 exceeds 80 columns
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-02-15--00-00 (tests: 1443)

Commit Message

Alex Henrie Feb. 14, 2024, 6:26 a.m. UTC 
RFC 8981 defines REGEN_ADVANCE as follows:

REGEN_ADVANCE = 2 + (TEMP_IDGEN_RETRIES * DupAddrDetectTransmits * RetransTimer / 1000)

Thus, allowing it to be less than 2 seconds is technically a protocol
violation.

Link: https://datatracker.ietf.org/doc/html/rfc8981#name-defined-protocol-parameters
Signed-off-by: Alex Henrie <alexhenrie24@gmail.com>
---
 Documentation/networking/ip-sysctl.rst |  4 ++--
 net/ipv6/addrconf.c                    | 15 +++++++++------
 2 files changed, 11 insertions(+), 8 deletions(-)

Comments

David Ahern Feb. 14, 2024, 3:38 p.m. UTC | #1 
On 2/13/24 11:26 PM, Alex Henrie wrote:
> RFC 8981 defines REGEN_ADVANCE as follows:
> 
> REGEN_ADVANCE = 2 + (TEMP_IDGEN_RETRIES * DupAddrDetectTransmits * RetransTimer / 1000)
> 
> Thus, allowing it to be less than 2 seconds is technically a protocol
> violation.
> 
> Link: https://datatracker.ietf.org/doc/html/rfc8981#name-defined-protocol-parameters
> Signed-off-by: Alex Henrie <alexhenrie24@gmail.com>
> ---
>  Documentation/networking/ip-sysctl.rst |  4 ++--
>  net/ipv6/addrconf.c                    | 15 +++++++++------
>  2 files changed, 11 insertions(+), 8 deletions(-)
> 

Alex: if no changes are made to a specific patch, then you should keep
any reviewed by tags on the next version.

Reviewed-by: David Ahern <dsahern@kernel.org>
diff mbox series

Patch

diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst
index 7afff42612e9..458305931345 100644
--- a/Documentation/networking/ip-sysctl.rst
+++ b/Documentation/networking/ip-sysctl.rst
@@ -2503,7 +2503,7 @@  use_tempaddr - INTEGER
 
 temp_valid_lft - INTEGER
 	valid lifetime (in seconds) for temporary addresses. If less than the
-	minimum required lifetime (typically 5 seconds), temporary addresses
+	minimum required lifetime (typically 5-7 seconds), temporary addresses
 	will not be created.
 
 	Default: 172800 (2 days)
@@ -2511,7 +2511,7 @@  temp_valid_lft - INTEGER
 temp_prefered_lft - INTEGER
 	Preferred lifetime (in seconds) for temporary addresses. If
 	temp_prefered_lft is less than the minimum required lifetime (typically
-	5 seconds), temporary addresses will not be created. If
+	5-7 seconds), temporary addresses will not be created. If
 	temp_prefered_lft is greater than temp_valid_lft, the preferred lifetime
 	is temp_valid_lft.
 
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index ca1b719323c0..68516493404a 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -1339,6 +1339,13 @@  static void ipv6_del_addr(struct inet6_ifaddr *ifp)
 	in6_ifa_put(ifp);
 }
 
+static unsigned long ipv6_get_regen_advance(struct inet6_dev *idev)
+{
+	return 2 + idev->cnf.regen_max_retry *
+			idev->cnf.dad_transmits *
+			max(NEIGH_VAR(idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
+}
+
 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, bool block)
 {
 	struct inet6_dev *idev = ifp->idev;
@@ -1380,9 +1387,7 @@  static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, bool block)
 
 	age = (now - ifp->tstamp) / HZ;
 
-	regen_advance = idev->cnf.regen_max_retry *
-			idev->cnf.dad_transmits *
-			max(NEIGH_VAR(idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
+	regen_advance = ipv6_get_regen_advance(idev);
 
 	/* recalculate max_desync_factor each time and update
 	 * idev->desync_factor if it's larger
@@ -4595,9 +4600,7 @@  static void addrconf_verify_rtnl(struct net *net)
 			    !ifp->regen_count && ifp->ifpub) {
 				/* This is a non-regenerated temporary addr. */
 
-				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
-					ifp->idev->cnf.dad_transmits *
-					max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
+				unsigned long regen_advance = ipv6_get_regen_advance(ifp->idev);
 
 				if (age + regen_advance >= ifp->prefered_lft) {
 					struct inet6_ifaddr *ifpub = ifp->ifpub;