From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Jianlin Shi <jishi@redhat.com>,
Sabrina Dubroca <sd@queasysnail.net>,
Stefano Brivio <sbrivio@redhat.com>,
"David S. Miller" <davem@davemloft.net>
Subject: [PATCH 4.4 23/36] net: ipv4: dont allow setting net.ipv4.route.min_pmtu below 68
Date: Fri, 9 Mar 2018 16:18:39 -0800 [thread overview]
Message-ID: <20180310001808.625785589@linuxfoundation.org> (raw)
In-Reply-To: <20180310001807.213987241@linuxfoundation.org>
4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Sabrina Dubroca <sd@queasysnail.net>
[ Upstream commit c7272c2f1229125f74f22dcdd59de9bbd804f1c8 ]
According to RFC 1191 sections 3 and 4, ICMP frag-needed messages
indicating an MTU below 68 should be rejected:
A host MUST never reduce its estimate of the Path MTU below 68
octets.
and (talking about ICMP frag-needed's Next-Hop MTU field):
This field will never contain a value less than 68, since every
router "must be able to forward a datagram of 68 octets without
fragmentation".
Furthermore, by letting net.ipv4.route.min_pmtu be set to negative
values, we can end up with a very large PMTU when (-1) is cast into u32.
Let's also make ip_rt_min_pmtu a u32, since it's only ever compared to
unsigned ints.
Reported-by: Jianlin Shi <jishi@redhat.com>
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/ipv4/route.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -126,10 +126,13 @@ static int ip_rt_redirect_silence __read
static int ip_rt_error_cost __read_mostly = HZ;
static int ip_rt_error_burst __read_mostly = 5 * HZ;
static int ip_rt_mtu_expires __read_mostly = 10 * 60 * HZ;
-static int ip_rt_min_pmtu __read_mostly = 512 + 20 + 20;
+static u32 ip_rt_min_pmtu __read_mostly = 512 + 20 + 20;
static int ip_rt_min_advmss __read_mostly = 256;
static int ip_rt_gc_timeout __read_mostly = RT_GC_TIMEOUT;
+
+static int ip_min_valid_pmtu __read_mostly = IPV4_MIN_MTU;
+
/*
* Interface to generic destination cache.
*/
@@ -2765,7 +2768,8 @@ static struct ctl_table ipv4_route_table
.data = &ip_rt_min_pmtu,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = &ip_min_valid_pmtu,
},
{
.procname = "min_adv_mss",
next prev parent reply other threads:[~2018-03-10 0:18 UTC|newest]
Thread overview: 54+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-03-10 0:18 [PATCH 4.4 00/36] 4.4.121-stable review Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 01/36] tpm: st33zp24: fix potential buffer overruns caused by bit glitches on the bus Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 02/36] tpm_i2c_infineon: " Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 03/36] tpm_i2c_nuvoton: " Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 04/36] ALSA: usb-audio: Add a quirck for B&W PX headphones Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 05/36] ALSA: hda: Add a power_save blacklist Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 06/36] cpufreq: s3c24xx: Fix broken s3c_cpufreq_init() Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 07/36] media: m88ds3103: dont call a non-initalized function Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 08/36] nospec: Allow index argument to have const-qualified type Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 09/36] ARM: mvebu: Fix broken PL310_ERRATA_753970 selects Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 10/36] KVM: mmu: Fix overlap between public and private memslots Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 11/36] x86/syscall: Sanitize syscall table de-references under speculation fix Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 12/36] btrfs: Dont clear SGID when inheriting ACLs Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 13/36] ARM: dts: LogicPD Torpedo: Fix I2C1 pinmux Greg Kroah-Hartman
2018-03-12 23:29 ` Ben Hutchings
2018-03-14 21:31 ` Adam Ford
2018-03-16 12:32 ` Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 14/36] x86/apic/vector: Handle legacy irq data correctly Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 15/36] leds: do not overflow sysfs buffer in led_trigger_show Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 16/36] x86/spectre: Fix an error message Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 17/36] Revert "led: core: Fix brightness setting when setting delay_off=0" Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 18/36] bridge: check brport attr show in brport_show Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 19/36] fib_semantics: Dont match route with mismatching tclassid Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 20/36] hdlc_ppp: carrier detect ok, dont turn off negotiation Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 21/36] ipv6 sit: work around bogus gcc-8 -Wrestrict warning Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 22/36] net: fix race on decreasing number of TX queues Greg Kroah-Hartman
2018-03-10 0:18 ` Greg Kroah-Hartman [this message]
2018-03-10 0:18 ` [PATCH 4.4 24/36] netlink: ensure to loop over all netns in genlmsg_multicast_allns() Greg Kroah-Hartman
2018-03-13 0:04 ` Ben Hutchings
2018-03-14 17:06 ` Nicolas Dichtel
2018-03-14 20:10 ` [PATCH net] netlink: avoid a double skb free in genlmsg_mcast() Nicolas Dichtel
2018-03-16 16:36 ` David Miller
2018-03-10 0:18 ` [PATCH 4.4 25/36] ppp: prevent unregistered channels from connecting to PPP units Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 26/36] udplite: fix partial checksum initialization Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 27/36] sctp: fix dst refcnt leak in sctp_v4_get_dst Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 28/36] sctp: fix dst refcnt leak in sctp_v6_get_dst() Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 29/36] s390/qeth: fix SETIP command handling Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 30/36] s390/qeth: fix IPA command submission race Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 31/36] sctp: verify size of a new chunk in _sctp_make_chunk() Greg Kroah-Hartman
2018-03-13 0:46 ` Ben Hutchings
2018-03-13 9:56 ` Greg Kroah-Hartman
2018-03-14 16:23 ` Ben Hutchings
2018-03-10 0:18 ` [PATCH 4.4 32/36] net: mpls: Pull common label check into helper Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 33/36] mpls, nospec: Sanitize array index in mpls_label_ok() Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 34/36] dm io: fix duplicate bio completion due to missing ref count Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 35/36] bpf, x64: implement retpoline for tail call Greg Kroah-Hartman
2018-03-10 0:18 ` [PATCH 4.4 36/36] btrfs: preserve i_mode if __btrfs_set_acl() fails Greg Kroah-Hartman
2018-03-10 0:50 ` [PATCH 4.4 00/36] 4.4.121-stable review Nathan Chancellor
2018-03-10 1:03 ` Greg Kroah-Hartman
2018-03-10 1:07 ` Nathan Chancellor
2018-03-10 5:16 ` Shuah Khan
2018-03-10 7:19 ` kernelci.org bot
2018-03-10 15:43 ` Guenter Roeck
2018-03-12 11:39 ` Naresh Kamboju
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