From 1a63cb91f0c2fcdeced6d6edee8d1d886583d139 Mon Sep 17 00:00:00 2001
From: Kuniyuki Iwashima <kuniyu@amazon.com>
Date: Mon, 18 Jul 2022 10:26:49 -0700
Subject: tcp: Fix a data-race around sysctl_tcp_retrans_collapse.

While reading sysctl_tcp_retrans_collapse, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its reader.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 net/ipv4/tcp_output.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'net/ipv4/tcp_output.c')

diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 51120407c570..c38e07b50639 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -3105,7 +3105,7 @@ static void tcp_retrans_try_collapse(struct sock *sk, struct sk_buff *to,
 	struct sk_buff *skb = to, *tmp;
 	bool first = true;
 
-	if (!sock_net(sk)->ipv4.sysctl_tcp_retrans_collapse)
+	if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_retrans_collapse))
 		return;
 	if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN)
 		return;
-- 
cgit v1.2.3

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<tr><td><span title='2017-08-31 16:19:13 +0100'>2017-08-31</span></td><td><a href='/linux/commit/arch/arm/boot/dts/ls1021a.dtsi?id=df3015888d88479ea5da914330c87af58987886b&amp;follow=1'>arm: dts: ls1021a: Share all MSIs</a></td><td>Minghuan Lian</td><td>1</td><td><span class='deletions'>-2</span>/<span class='insertions'>+2</span></td></tr>
<tr><td><span title='2017-08-31 16:19:05 +0100'>2017-08-31</span></td><td><a href='/linux/commit/arch/arm64/boot/dts/freescale/fsl-ls1043a.dtsi?id=f93aff6263f3de4428daf0ea8872f6c0121438ec&amp;follow=1'>arm64: dts: ls1043a: Fix typo of MSI compatible string</a></td><td>Minghuan Lian</td><td>1</td><td><span class='deletions'>-3</span>/<span class='insertions'>+3</span></td></tr>
<tr><td><span title='2017-08-31 16:18:59 +0100'>2017-08-31</span></td><td><a href='/linux/commit/arch/arm/boot/dts/ls1021a.dtsi?id=c9041ea324b0f2bec624c385c4a8bbd21d453e9b&amp;follow=1'>arm: dts: ls1021a: Fix typo of MSI compatible string</a></td><td>Minghuan Lian</td><td>1</td><td><span class='deletions'>-2</span>/<span class='insertions'>+2</span></td></tr>
<tr><td><span title='2017-08-31 16:18:48 +0100'>2017-08-31</span></td><td><a href='/linux/commit/drivers/irqchip/irq-ls-scfg-msi.c?id=d35b2c99520bbc018d645ddcbc0332f36a985a56&amp;follow=1'>irqchip/ls-scfg-msi: Fix typo of MSI compatible strings</a></td><td>Minghuan Lian</td><td>2</td><td><span class='deletions'>-5</span>/<span class='insertions'>+7</span></td></tr>
<tr><td><span title='2017-08-31 15:32:18 +0100'>2017-08-31</span></td><td><a href='/linux/commit/drivers/irqchip/irq-bcm7120-l2.c?id=b304605f0a2c25c028e26a9a3f6aa798693a4051&amp;follow=1'>irqchip/irq-bcm7120-l2: Use correct I/O accessors for irq_fwd_mask</a></td><td>Florian Fainelli</td><td>1</td><td><span class='deletions'>-6</span>/<span class='insertions'>+4</span></td></tr>
<tr><td><span title='2017-08-31 15:31:43 +0100'>2017-08-31</span></td><td><a href='/linux/commit/drivers/irqchip/irq-mmp.c?id=c8c7d93dcbf21ebcf7486473e7a9a6addf49caa9&amp;follow=1'>irqchip/mmp: Make mmp_intc_conf const</a></td><td>Bhumika Goyal</td><td>1</td><td><span class='deletions'>-2</span>/<span class='insertions'>+2</span></td></tr>
<tr><td><span title='2017-08-31 15:31:43 +0100'>2017-08-31</span></td><td><a href='/linux/commit/drivers/irqchip/irq-gic.c?id=73c4c37c7e6ecc3cf921d182b733c9322ebed117&amp;follow=1'>irqchip/gic: Make irq_chip const</a></td><td>Bhumika Goyal</td><td>1</td><td><span class='deletions'>-1</span>/<span class='insertions'>+1</span></td></tr>
<tr><td><span title='2017-08-31 15:31:42 +0100'>2017-08-31</span></td><td><a href='/linux/commit/include/linux/irqchip/arm-gic-common.h?id=4bdf502517288662d883fbaa915874790f51a2cd&amp;follow=1'>irqchip/gic-v3: Advertise GICv4 support to KVM</a></td><td>Marc Zyngier</td><td>2</td><td><span class='deletions'>-0</span>/<span class='insertions'>+4</span></td></tr>
<tr><td><span title='2017-08-31 15:31:42 +0100'>2017-08-31</span></td><td><a href='/linux/commit/include/linux/irqchip/arm-gic-v4.h?id=3d63cb53e221d8ab347e94aeac0b5511857beb7f&amp;follow=1'>irqchip/gic-v4: Enable low-level GICv4 operations</a></td><td>Marc Zyngier</td><td>4</td><td><span class='deletions'>-2</span>/<span class='insertions'>+18</span></td></tr>
<tr><td><span title='2017-08-31 15:31:42 +0100'>2017-08-31</span></td><td><a href='/linux/commit/drivers/irqchip/irq-gic-v4.c?id=7954907bedafd0f8e81633803945cb304793b29d&amp;follow=1'>irqchip/gic-v4: Add some basic documentation</a></td><td>Marc Zyngier</td><td>1</td><td><span class='deletions'>-0</span>/<span class='insertions'>+71</span></td></tr>
<tr><td><span title='2017-08-31 15:31:41 +0100'>2017-08-31</span></td><td><a href='/linux/commit/include/linux/irqchip/arm-gic-v4.h?id=f2eac75de435871d5a497f8b557874a2a8a7b264&amp;follow=1'>irqchip/gic-v4: Add VLPI configuration interface</a></td><td>Marc Zyngier</td><td>2</td><td><span class='deletions'>-0</span>/<span class='insertions'>+46</span></td></tr>
<tr><td><span title='2017-08-31 15:31:41 +0100'>2017-08-31</span></td><td><a href='/linux/commit/include/linux/irqchip/arm-gic-v4.h?id=eab84318c2811e3f38c080efcc7f709f51bb8370&amp;follow=1'>irqchip/gic-v4: Add VPE command interface</a></td><td>Marc Zyngier</td><td>2</td><td><span class='deletions'>-0</span>/<span class='insertions'>+27</span></td></tr>
<tr><td><span title='2017-08-31 15:31:40 +0100'>2017-08-31</span></td><td><a href='/linux/commit/include/linux/irqchip/arm-gic-v4.h?id=7de5c0af9c7c717f9052e6d75b24f90050e6a56e&amp;follow=1'>irqchip/gic-v4: Add per-VM VPE domain creation</a></td><td>Marc Zyngier</td><td>2</td><td><span class='deletions'>-0</span>/<span class='insertions'>+77</span></td></tr>
<tr><td><span title='2017-08-31 15:31:40 +0100'>2017-08-31</span></td><td><a href='/linux/commit/include/linux/irqchip/arm-gic-v3.h?id=d51c4b4da7f8fae8c884e3b89fdab906f66da28a&amp;follow=1'>irqchip/gic-v3-its: Set implementation defined bit to enable VLPIs</a></td><td>Marc Zyngier</td><td>2</td><td><span class='deletions'>-2</span>/<span class='insertions'>+6</span></td></tr>
<tr><td><span title='2017-08-31 15:31:39 +0100'>2017-08-31</span></td><td><a href='/linux/commit/drivers/irqchip/irq-gic-v3-its.c?id=e57a3e2847ad74bd3285287b0effc1cfcc3d8806&amp;follow=1'>irqchip/gic-v3-its: Allow doorbell interrupts to be injected/cleared</a></td><td>Marc Zyngier</td><td>1</td><td><span class='deletions'>-0</span>/<span class='insertions'>+31</span></td></tr>
<tr><td><span title='2017-08-31 15:31:39 +0100'>2017-08-31</span></td><td><a href='/linux/commit/drivers/irqchip/irq-gic-v3-its.c?id=958b90d162b4ad40a7a809af5f56f3744d73ab84&amp;follow=1'>irqchip/gic-v3-its: Move pending doorbell after VMOVP</a></td><td>Marc Zyngier</td><td>1</td><td><span class='deletions'>-2</span>/<span class='insertions'>+32</span></td></tr>
<tr><td><span title='2017-08-31 15:31:39 +0100'>2017-08-31</span></td><td><a href='/linux/commit/include/linux/irqchip/arm-gic-v4.h?id=20b3d54ecba51c5fe476eea94ffdc463559c5c85&amp;follow=1'>irqchip/gic-v3-its: Add device proxy for VPE management if !DirectLpi</a></td><td>Marc Zyngier</td><td>2</td><td><span class='deletions'>-6</span>/<span class='insertions'>+147</span></td></tr>
<tr><td><span title='2017-08-31 15:31:38 +0100'>2017-08-31</span></td><td><a href='/linux/commit/drivers/irqchip/irq-gic-v3-its.c?id=93f94ea0548c2628efe7d57e0989f06a14cedb53&amp;follow=1'>irqchip/gic-v3-its: Make LPI allocation optional on device creation</a></td><td>Marc Zyngier</td><td>1</td><td><span class='deletions'>-7</span>/<span class='insertions'>+14</span></td></tr>
<tr><td><span title='2017-08-31 15:31:38 +0100'>2017-08-31</span></td><td><a href='/linux/commit/drivers/irqchip/irq-gic-v3-its.c?id=f6a91da7c788ac7345305ee291d0b205d2f5a70f&amp;follow=1'>irqchip/gic-v3-its: Add VPE interrupt masking</a></td><td>Marc Zyngier</td><td>3</td><td><span class='deletions'>-0</span>/<span class='insertions'>+41</span></td></tr>
<tr><td><span title='2017-08-31 15:31:37 +0100'>2017-08-31</span></td><td><a href='/linux/commit/drivers/irqchip/irq-gic-v3-its.c?id=3171a47a22eedfb6e97803fb193fc98cdb61d90f&amp;follow=1'>irqchip/gic-v3-its: Add VPE affinity changes</a></td><td>Marc Zyngier</td><td>1</td><td><span class='deletions'>-0</span>/<span class='insertions'>+96</span></td></tr>
<tr><td><span title='2017-08-31 15:31:37 +0100'>2017-08-31</span></td><td><a href='/linux/commit/drivers/irqchip/irq-gic-v3-its.c?id=5e2f764234bd0ef9542902fb608e525c41e0d7ee&amp;follow=1'>irqchip/gic-v3-its: Add VPE invalidation hook</a></td><td>Marc Zyngier</td><td>1</td><td><span class='deletions'>-0</span>/<span class='insertions'>+4</span></td></tr>
<tr><td><span title='2017-08-31 15:31:36 +0100'>2017-08-31</span></td><td><a href='/linux/commit/include/linux/irqchip/arm-gic-v3.h?id=e643d80340363c9d172abfbe437537196cfc1643&amp;follow=1'>irqchip/gic-v3-its: Add VPE scheduling</a></td><td>Marc Zyngier</td><td>2</td><td><span class='deletions'>-0</span>/<span class='insertions'>+143</span></td></tr>
<tr><td><span title='2017-08-31 15:31:36 +0100'>2017-08-31</span></td><td><a href='/linux/commit/include/linux/irqchip/arm-gic-v3.h?id=3ca63f363f3f8fe457482c53d5c86d83bff21e64&amp;follow=1'>irqchip/gic-v3-its: Add VPENDBASER/VPROPBASER accessors</a></td><td>Marc Zyngier</td><td>3</td><td><span class='deletions'>-0</span>/<span class='insertions'>+38</span></td></tr>
<tr><td><span title='2017-08-31 15:31:36 +0100'>2017-08-31</span></td><td><a href='/linux/commit/drivers/irqchip/irq-gic-v3-its.c?id=eb78192be2833484b0f7b506d217a40621215251&amp;follow=1'>irqchip/gic-v3-its: Add VPE irq domain [de]activation</a></td><td>Marc Zyngier</td><td>1</td><td><span class='deletions'>-0</span>/<span class='insertions'>+102</span></td></tr>
<tr><td><span title='2017-08-31 15:31:35 +0100'>2017-08-31</span></td><td><a href='/linux/commit/drivers/irqchip/irq-gic-v3-its.c?id=7d75bbb4bc1ad90386776459d37e4ddfe605671e&amp;follow=1'>irqchip/gic-v3-its: Add VPE irq domain allocation/teardown</a></td><td>Marc Zyngier</td><td>1</td><td><span class='deletions'>-0</span>/<span class='insertions'>+169</span></td></tr>
<tr><td><span title='2017-08-31 15:31:35 +0100'>2017-08-31</span></td><td><a href='/linux/commit/drivers/irqchip/irq-gic-v3-its.c?id=8fff27aec182ed4d6fe15d1373fc6b35cdfcda0f&amp;follow=1'>irqchip/gic-v3-its: Add VPE domain infrastructure</a></td><td>Marc Zyngier</td><td>1</td><td><span class='deletions'>-1</span>/<span class='insertions'>+30</span></td></tr>
<tr><td><span title='2017-08-31 15:31:34 +0100'>2017-08-31</span></td><td><a href='/linux/commit/drivers/irqchip/irq-gic-v3-its.c?id=015ec0386ab69a5b6b21f6c1559b242f4540de9f&amp;follow=1'>irqchip/gic-v3-its: Add VLPI configuration handling</a></td><td>Marc Zyngier</td><td>1</td><td><span class='deletions'>-5</span>/<span class='insertions'>+70</span></td></tr>
<tr><td><span title='2017-08-31 15:31:34 +0100'>2017-08-31</span></td><td><a href='/linux/commit/drivers/irqchip/irq-gic-v3-its.c?id=d011e4e654d7f519bf892995b9f4b453dbf8a3e5&amp;follow=1'>irqchip/gic-v3-its: Add VLPI map/unmap operations</a></td><td>Marc Zyngier</td><td>1</td><td><span class='deletions'>-3</span>/<span class='insertions'>+247</span></td></tr>
<tr><td><span title='2017-08-31 15:31:33 +0100'>2017-08-31</span></td><td><a href='/linux/commit/drivers/irqchip/irq-gic-v3-its.c?id=c808eea8f763a996409656df83c41b8ec628060b&amp;follow=1'>irqchip/gic-v3-its: Add VLPI configuration hook</a></td><td>Marc Zyngier</td><td>1</td><td><span class='deletions'>-0</span>/<span class='insertions'>+24</span></td></tr>
<tr><td><span title='2017-08-31 15:31:33 +0100'>2017-08-31</span></td><td><a href='/linux/commit/include/linux/irqchip/arm-gic-v3.h?id=d7276b80e752acaaf30f04e62d0e986b5bced2df&amp;follow=1'>irqchip/gic-v3-its: Add GICv4 ITS command definitions</a></td><td>Marc Zyngier</td><td>2</td><td><span class='deletions'>-1</span>/<span class='insertions'>+13</span></td></tr>