From: Alex Henrie <alexhenrie24@gmail.com>
To: netdev@vger.kernel.org, jbohac@suse.cz,
benoit.boissinot@ens-lyon.org, davem@davemloft.net,
hideaki.yoshifuji@miraclelinux.com, dsahern@kernel.org,
pabeni@redhat.com, kuba@kernel.org
Cc: Alex Henrie <alexhenrie24@gmail.com>
Subject: [PATCH v3] net: ipv6/addrconf: avoid integer underflow in ipv6_create_tempaddr
Date: Thu, 31 Aug 2023 22:41:27 -0600 [thread overview]
Message-ID: <20230901044219.10062-1-alexhenrie24@gmail.com> (raw)
In-Reply-To: <20230829054623.104293-2-alexhenrie24@gmail.com>
The existing code incorrectly casted a negative value (the result of a
subtraction) to an unsigned value without checking. For example, if
/proc/sys/net/ipv6/conf/*/temp_prefered_lft was set to 1, the preferred
lifetime would jump to 4 billion seconds. On my machine and network the
shortest lifetime that avoided underflow was 3 seconds.
Fixes: 76506a986dc3 ("IPv6: fix DESYNC_FACTOR")
Signed-off-by: Alex Henrie <alexhenrie24@gmail.com>
---
Changes from v2:
- Use conventional format for "Fixes" line
- Send separately and leave the other four patches for later
---
net/ipv6/addrconf.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 967913ad65e5..0b6ee962c84e 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -1378,7 +1378,7 @@ static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, bool block)
* idev->desync_factor if it's larger
*/
cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
- max_desync_factor = min_t(__u32,
+ max_desync_factor = min_t(long,
idev->cnf.max_desync_factor,
cnf_temp_preferred_lft - regen_advance);
--
2.42.0
next prev parent reply other threads:[~2023-09-01 4:43 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-08-21 1:11 [PATCH] ipv6/addrconf: clamp preferred_lft to the minimum instead of erroring Alex Henrie
2023-08-22 9:54 ` Paolo Abeni
2023-08-23 3:41 ` Alex Henrie
2023-08-23 3:45 ` David Ahern
2023-08-23 8:36 ` Jiri Bohac
2023-08-23 11:00 ` Paolo Abeni
2023-08-29 5:44 ` [PATCH v2 0/5] net: ipv6/addrconf: ensure that temporary addresses' preferred lifetimes are in the valid range Alex Henrie
2023-08-29 5:44 ` [PATCH v2 1/5] net: ipv6/addrconf: avoid integer underflow in ipv6_create_tempaddr Alex Henrie
2023-09-01 4:41 ` Alex Henrie [this message]
2023-09-01 13:53 ` [PATCH v3] " David Ahern
2023-09-04 6:21 ` patchwork-bot+netdevbpf
2023-08-29 5:44 ` [PATCH v2 2/5] net: ipv6/addrconf: clamp preferred_lft to the maximum allowed Alex Henrie
2023-08-31 8:25 ` Paolo Abeni
2023-08-29 5:44 ` [PATCH v2 3/5] net: ipv6/addrconf: clamp preferred_lft to the minimum required Alex Henrie
2023-08-31 1:28 ` Jakub Kicinski
2023-08-31 5:40 ` Alex Henrie
2023-08-29 5:44 ` [PATCH v2 4/5] Documentation: networking: explain what happens if temp_valid_lft is too small Alex Henrie
2023-08-29 5:44 ` [PATCH v2 5/5] Documentation: networking: explain what happens if temp_prefered_lft is too small or too large Alex Henrie
2023-08-31 8:33 ` Paolo Abeni
2023-10-24 19:40 ` [PATCH resend 1/4] net: ipv6/addrconf: clamp preferred_lft to the maximum allowed Alex Henrie
2023-10-24 19:40 ` [PATCH resend 2/4] net: ipv6/addrconf: clamp preferred_lft to the minimum required Alex Henrie
2023-10-24 19:40 ` [PATCH resend 3/4] Documentation: networking: explain what happens if temp_valid_lft is too small Alex Henrie
2023-10-24 19:40 ` [PATCH resend 4/4] Documentation: networking: explain what happens if temp_prefered_lft is too small or too large Alex Henrie
2023-10-24 19:48 ` [PATCH resend 1/4] net: ipv6/addrconf: clamp preferred_lft to the maximum allowed Jakub Kicinski
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