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| author | Alex Henrie <alexhenrie24@gmail.com> | 2023-12-29 21:32:44 -0700 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-01-02 14:58:46 -0800 |
| commit | 8cdafdd94654ba418648d039c48e7a90508c1982 (patch) | |
| tree | 1bf3088430d4c89d0282a93651b3f5a31756075e | |
| parent | 61fa2493ca76fd7bb74e13f0205274f4ab0aa696 (diff) | |
| download | lwn-8cdafdd94654ba418648d039c48e7a90508c1982.tar.gz lwn-8cdafdd94654ba418648d039c48e7a90508c1982.zip | |
Revert "net: ipv6/addrconf: clamp preferred_lft to the minimum required"
The commit had a bug and might not have been the right approach anyway.
Fixes: 629df6701c8a ("net: ipv6/addrconf: clamp preferred_lft to the minimum required")
Fixes: ec575f885e3e ("Documentation: networking: explain what happens if temp_prefered_lft is too small or too large")
Reported-by: Dan Moulding <dan@danm.net>
Closes: https://lore.kernel.org/netdev/20231221231115.12402-1-dan@danm.net/
Link: https://lore.kernel.org/netdev/CAMMLpeTdYhd=7hhPi2Y7pwdPCgnnW5JYh-bu3hSc7im39uxnEA@mail.gmail.com/
Signed-off-by: Alex Henrie <alexhenrie24@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20231230043252.10530-1-alexhenrie24@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | Documentation/networking/ip-sysctl.rst | 2 | ||||
| -rw-r--r-- | net/ipv6/addrconf.c | 18 |
2 files changed, 6 insertions, 14 deletions
diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst index 4dfe0d9a57bb..7afff42612e9 100644 --- a/Documentation/networking/ip-sysctl.rst +++ b/Documentation/networking/ip-sysctl.rst @@ -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), the preferred lifetime is the minimum required. If + 5 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 2692a7b24c40..733ace18806c 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -1407,23 +1407,15 @@ retry: write_unlock_bh(&idev->lock); - /* From RFC 4941: - * - * A temporary address is created only if this calculated Preferred - * Lifetime is greater than REGEN_ADVANCE time units. In - * particular, an implementation must not create a temporary address - * with a zero Preferred Lifetime. - * - * Clamp the preferred lifetime to a minimum of regen_advance, unless - * that would exceed valid_lft. - * + /* A temporary address is created only if this calculated Preferred + * Lifetime is greater than REGEN_ADVANCE time units. In particular, + * an implementation must not create a temporary address with a zero + * Preferred Lifetime. * Use age calculation as in addrconf_verify to avoid unnecessary * temporary addresses being generated. */ age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ; - if (cfg.preferred_lft <= regen_advance + age) - cfg.preferred_lft = regen_advance + age + 1; - if (cfg.preferred_lft > cfg.valid_lft) { + if (cfg.preferred_lft <= regen_advance + age) { in6_ifa_put(ifp); in6_dev_put(idev); ret = -1; |