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**issue处理注意事项:** 
**1. 当前issue受影响的分支提交pr时, 须在pr描述中填写当前issue编号进行关联, 否则无法关闭当前issue;**
**2. 模板内容需要填写完整, 无论是受影响或者不受影响都需要填写完整内容,未引入的分支不需要填写, 否则无法关闭当前issue;**
**3. 以下为模板中需要填写完整的内容, 请复制到评论区回复, 注: 内容的标题名称(影响性分析说明, openEuler评分, 受影响版本排查(受影响/不受影响), 修复是否涉及abi变化(是/否), 原因说明)不能省略,省略后cve-manager将无法正常解析填写内容.**
************************************************************************
影响性分析说明:

openEuler评分: (评分和向量)

受影响版本排查(受影响/不受影响): 
1.master(6.6.0):
2.openEuler-20.03-LTS-SP4(4.19.90):
3.openEuler-22.03-LTS-SP1(5.10.0):
4.openEuler-22.03-LTS-SP3(5.10.0):
5.openEuler-22.03-LTS-SP4(5.10.0):
6.openEuler-24.03-LTS(6.6.0):
7.openEuler-24.03-LTS-Next(6.6.0):
8.openEuler-24.03-LTS-SP1(6.6.0):

修复是否涉及abi变化(是/否)：
1.master(6.6.0):
2.openEuler-20.03-LTS-SP4(4.19.90):
3.openEuler-22.03-LTS-SP1(5.10.0):
4.openEuler-22.03-LTS-SP3(5.10.0):
5.openEuler-22.03-LTS-SP4(5.10.0):
6.openEuler-24.03-LTS(6.6.0):
7.openEuler-24.03-LTS-Next(6.6.0):
8.openEuler-24.03-LTS-SP1(6.6.0):

原因说明：
1.master(6.6.0):
2.openEuler-20.03-LTS-SP4(4.19.90):
3.openEuler-22.03-LTS-SP1(5.10.0):
4.openEuler-22.03-LTS-SP3(5.10.0):
5.openEuler-22.03-LTS-SP4(5.10.0):
6.openEuler-24.03-LTS(6.6.0):
7.openEuler-24.03-LTS-Next(6.6.0):
8.openEuler-24.03-LTS-SP1(6.6.0):

issue处理具体操作请参考: 
https://gitee.com/openeuler/cve-manager/blob/master/cve-vulner-manager/doc/md/manual.md
pr关联issue具体操作请参考:
https://gitee.com/help/articles/4142

CVE-2024-56644

影响性分析说明：
In the Linux kernel, the following vulnerability has been resolved:

net/ipv6: release expired exception dst cached in socket

Dst objects get leaked in ip6_negative_advice() when this function is
executed for an expired IPv6 route located in the exception table. There
are several conditions that must be fulfilled for the leak to occur:
* an ICMPv6 packet indicating a change of the MTU for the path is received,
  resulting in an exception dst being created
* a TCP connection that uses the exception dst for routing packets must
  start timing out so that TCP begins retransmissions
* after the exception dst expires, the FIB6 garbage collector must not run
  before TCP executes ip6_negative_advice() for the expired exception dst

When TCP executes ip6_negative_advice() for an exception dst that has
expired and if no other socket holds a reference to the exception dst, the
refcount of the exception dst is 2, which corresponds to the increment
made by dst_init() and the increment made by the TCP socket for which the
connection is timing out. The refcount made by the socket is never
released. The refcount of the dst is decremented in sk_dst_reset() but
that decrement is counteracted by a dst_hold() intentionally placed just
before the sk_dst_reset() in ip6_negative_advice(). After
ip6_negative_advice() has finished, there is no other object tied to the
dst. The socket lost its reference stored in sk_dst_cache and the dst is
no longer in the exception table. The exception dst becomes a leaked
object.

As a result of this dst leak, an unbalanced refcount is reported for the
loopback device of a net namespace being destroyed under kernels that do
not contain e5f80fcf869a (&#34;ipv6: give an IPv6 dev to blackhole_netdev&#34;):
unregister_netdevice: waiting for lo to become free. Usage count = 2

Fix the dst leak by removing the dst_hold() in ip6_negative_advice(). The
patch that introduced the dst_hold() in ip6_negative_advice() was
92f1655aa2b22 (&#34;net: fix __dst_negative_advice() race&#34;). But 92f1655aa2b22
merely refactored the code with regards to the dst refcount so the issue
was present even before 92f1655aa2b22. The bug was introduced in
54c1a859efd9f (&#34;ipv6: Don&#39;t drop cache route entry unless timer actually
expired.&#34;) where the expired cached route is deleted and the sk_dst_cache
member of the socket is set to NULL by calling dst_negative_advice() but
the refcount belonging to the socket is left unbalanced.

The IPv4 version - ipv4_negative_advice() - is not affected by this bug.
When the TCP connection times out ipv4_negative_advice() merely resets the
sk_dst_cache of the socket while decrementing the refcount of the
exception dst.

The Linux kernel CVE team has assigned CVE-2024-56644 to this issue.

openEuler评分:(评分和向量)
4.7
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

受影响版本排查(受影响/不受影响):
1.openEuler-20.03-LTS-SP4:受影响
2.openEuler-22.03-LTS-SP1:受影响
3.openEuler-22.03-LTS-SP3:受影响
4.openEuler-22.03-LTS-SP4:受影响
5.master(6.1.0):不受影响
6.openEuler-24.03-LTS:受影响
7.openEuler-24.03-LTS-Next:不受影响
8.openEuler-24.03-LTS-SP1:受影响

修复是否涉及abi变化(是/否)：
1.openEuler-20.03-LTS-SP4:否
2.openEuler-22.03-LTS-SP1:否
3.openEuler-22.03-LTS-SP3:否
4.master(6.1.0):否
5.openEuler-24.03-LTS:否
6.openEuler-24.03-LTS-Next:否
7.openEuler-22.03-LTS-SP4:否
8.openEuler-24.03-LTS-SP1:否

原因说明：
1.master(23.08.5):不受影响-漏洞代码不能被攻击者触发
2.openEuler-20.03-LTS-SP4:正常修复
3.openEuler-22.03-LTS-SP1:正常修复
4.openEuler-22.03-LTS-SP3:正常修复
5.openEuler-22.03-LTS-SP4:正常修复
6.openEuler-24.03-LTS:正常修复
7.openEuler-24.03-LTS-Next:不受影响-漏洞代码不能被攻击者触发
8.openEuler-24.03-LTS-SP1:正常修复

@sanglipeng 经过 cve-manager 解析, 已分析的内容如下表所示:
| 状态  | 分析项目 | 内容 |
|:--:|:--:|---------|
|已分析|1.影响性分析说明|In the Linux kernel, the following vulnerability has been resolved:net/ipv6: release expired exception dst cached in socketDst objects get leaked in ip6_negative_advice() when this function isexecuted for an expired IPv6 route located in the exception table. Thereare several conditions that must be fulfilled for the leak to occur:* an ICMPv6 packet indicating a change of the MTU for the path is received,  resulting in an exception dst being created* a TCP connection that uses the exception dst for routing packets must  start timing out so that TCP begins retransmissions* after the exception dst expires, the FIB6 garbage collector must not run  before TCP executes ip6_negative_advice() for the expired exception dstWhen TCP executes ip6_negative_advice() for an exception dst that hasexpired and if no other socket holds a reference to the exception dst, therefcount of the exception dst is 2, which corresponds to the incrementmade by dst_init() and the increment made by the TCP socket for which theconnection is timing out. The refcount made by the socket is neverreleased. The refcount of the dst is decremented in sk_dst_reset() butthat decrement is counteracted by a dst_hold() intentionally placed justbefore the sk_dst_reset() in ip6_negative_advice(). Afterip6_negative_advice() has finished, there is no other object tied to thedst. The socket lost its reference stored in sk_dst_cache and the dst isno longer in the exception table. The exception dst becomes a leakedobject.As a result of this dst leak, an unbalanced refcount is reported for theloopback device of a net namespace being destroyed under kernels that donot contain e5f80fcf869a (&#34;ipv6: give an IPv6 dev to blackhole_netdev&#34;):unregister_netdevice: waiting for lo to become free. Usage count = 2Fix the dst leak by removing the dst_hold() in ip6_negative_advice(). Thepatch that introduced the dst_hold() in ip6_negative_advice() was92f1655aa2b22 (&#34;net: fix __dst_negative_advice() race&#34;). But 92f1655aa2b22merely refactored the code with regards to the dst refcount so the issuewas present even before 92f1655aa2b22. The bug was introduced in54c1a859efd9f (&#34;ipv6: Don&#39;t drop cache route entry unless timer actuallyexpired.&#34;) where the expired cached route is deleted and the sk_dst_cachemember of the socket is set to NULL by calling dst_negative_advice() butthe refcount belonging to the socket is left unbalanced.The IPv4 version - ipv4_negative_advice() - is not affected by this bug.When the TCP connection times out ipv4_negative_advice() merely resets thesk_dst_cache of the socket while decrementing the refcount of theexception dst.The Linux kernel CVE team has assigned CVE-2024-56644 to this issue.|
|已分析|2.openEulerScore|4.7|
|已分析|3.openEulerVector|AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H|
|已分析|4.受影响版本排查|openEuler-20.03-LTS-SP4:受影响,openEuler-22.03-LTS-SP1:受影响,openEuler-22.03-LTS-SP3:受影响,openEuler-22.03-LTS-SP4:受影响,openEuler-24.03-LTS:受影响,openEuler-24.03-LTS-SP1:受影响,master:不受影响,openEuler-24.03-LTS-Next:不受影响|
|已分析|5.是否涉及abi变化|openEuler-20.03-LTS-SP4:否,openEuler-22.03-LTS-SP1:否,openEuler-22.03-LTS-SP3:否,master:否,openEuler-24.03-LTS:否,openEuler-24.03-LTS-Next:否,openEuler-22.03-LTS-SP4:否,openEuler-24.03-LTS-SP1:否|
|已分析|6.原因说明|openEuler-20.03-LTS-SP4:正常修复,openEuler-22.03-LTS-SP1:正常修复,openEuler-22.03-LTS-SP3:正常修复,openEuler-22.03-LTS-SP4:正常修复,openEuler-24.03-LTS:正常修复,openEuler-24.03-LTS-SP1:正常修复,master:不受影响-漏洞代码不能被攻击者触发,openEuler-24.03-LTS-Next:不受影响-漏洞代码不能被攻击者触发|

**请确认分析内容的准确性, 确认无误后, 您可以进行后续步骤, 否则您可以继续分析.**

CVE-2024-56644

影响性分析说明：
In the Linux kernel, the following vulnerability has been resolved:

net/ipv6: release expired exception dst cached in socket

Dst objects get leaked in ip6_negative_advice() when this function is
executed for an expired IPv6 route located in the exception table. There
are several conditions that must be fulfilled for the leak to occur:
* an ICMPv6 packet indicating a change of the MTU for the path is received,
  resulting in an exception dst being created
* a TCP connection that uses the exception dst for routing packets must
  start timing out so that TCP begins retransmissions
* after the exception dst expires, the FIB6 garbage collector must not run
  before TCP executes ip6_negative_advice() for the expired exception dst

When TCP executes ip6_negative_advice() for an exception dst that has
expired and if no other socket holds a reference to the exception dst, the
refcount of the exception dst is 2, which corresponds to the increment
made by dst_init() and the increment made by the TCP socket for which the
connection is timing out. The refcount made by the socket is never
released. The refcount of the dst is decremented in sk_dst_reset() but
that decrement is counteracted by a dst_hold() intentionally placed just
before the sk_dst_reset() in ip6_negative_advice(). After
ip6_negative_advice() has finished, there is no other object tied to the
dst. The socket lost its reference stored in sk_dst_cache and the dst is
no longer in the exception table. The exception dst becomes a leaked
object.

As a result of this dst leak, an unbalanced refcount is reported for the
loopback device of a net namespace being destroyed under kernels that do
not contain e5f80fcf869a ("ipv6: give an IPv6 dev to blackhole_netdev"):
unregister_netdevice: waiting for lo to become free. Usage count = 2

Fix the dst leak by removing the dst_hold() in ip6_negative_advice(). The
patch that introduced the dst_hold() in ip6_negative_advice() was
92f1655aa2b22 ("net: fix __dst_negative_advice() race"). But 92f1655aa2b22
merely refactored the code with regards to the dst refcount so the issue
was present even before 92f1655aa2b22. The bug was introduced in
54c1a859efd9f ("ipv6: Don't drop cache route entry unless timer actually
expired.") where the expired cached route is deleted and the sk_dst_cache
member of the socket is set to NULL by calling dst_negative_advice() but
the refcount belonging to the socket is left unbalanced.

The IPv4 version - ipv4_negative_advice() - is not affected by this bug.
When the TCP connection times out ipv4_negative_advice() merely resets the
sk_dst_cache of the socket while decrementing the refcount of the
exception dst.

openEuler评分:(评分和向量)
2.5
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L

受影响版本排查(受影响/不受影响):
1.openEuler-20.03-LTS-SP4:受影响
2.openEuler-22.03-LTS-SP3:受影响
3.openEuler-22.03-LTS-SP4:受影响
4.master(6.6.0):不受影响
5.openEuler-24.03-LTS:受影响
6.openEuler-24.03-LTS-Next:不受影响
7.openEuler-24.03-LTS-SP1:受影响

原因说明:
1.openEuler-20.03-LTS-SP4:不修复-超出修复范围
2.openEuler-22.03-LTS-SP3:不修复-超出修复范围
3.openEuler-22.03-LTS-SP4:不修复-超出修复范围
4.master(6.6.0):不受影响-漏洞代码不能被攻击者触发
5.openEuler-24.03-LTS:正常修复
6.openEuler-24.03-LTS-Next:不受影响-漏洞代码不能被攻击者触发
7.openEuler-24.03-LTS-SP1:正常修复

修复是否涉及abi变化(是/否)：
1.openEuler-20.03-LTS-SP4:否
2.openEuler-22.03-LTS-SP3:否
3.master(23.08.5):否
4.openEuler-24.03-LTS:否
5.openEuler-24.03-LTS-Next:否
6.openEuler-22.03-LTS-SP4:否
7.openEuler-24.03-LTS-SP1:否

===========================================================

@sanglipeng 经过 cve-manager 解析, 已分析的内容如下表所示:
| 状态  | 分析项目 | 内容 |
|:--:|:--:|---------|
|已分析|1.影响性分析说明|In the Linux kernel, the following vulnerability has been resolved:net/ipv6: release expired exception dst cached in socketDst objects get leaked in ip6_negative_advice() when this function isexecuted for an expired IPv6 route located in the exception table. Thereare several conditions that must be fulfilled for the leak to occur:* an ICMPv6 packet indicating a change of the MTU for the path is received,  resulting in an exception dst being created* a TCP connection that uses the exception dst for routing packets must  start timing out so that TCP begins retransmissions* after the exception dst expires, the FIB6 garbage collector must not run  before TCP executes ip6_negative_advice() for the expired exception dstWhen TCP executes ip6_negative_advice() for an exception dst that hasexpired and if no other socket holds a reference to the exception dst, therefcount of the exception dst is 2, which corresponds to the incrementmade by dst_init() and the increment made by the TCP socket for which theconnection is timing out. The refcount made by the socket is neverreleased. The refcount of the dst is decremented in sk_dst_reset() butthat decrement is counteracted by a dst_hold() intentionally placed justbefore the sk_dst_reset() in ip6_negative_advice(). Afterip6_negative_advice() has finished, there is no other object tied to thedst. The socket lost its reference stored in sk_dst_cache and the dst isno longer in the exception table. The exception dst becomes a leakedobject.As a result of this dst leak, an unbalanced refcount is reported for theloopback device of a net namespace being destroyed under kernels that donot contain e5f80fcf869a ("ipv6: give an IPv6 dev to blackhole_netdev"):unregister_netdevice: waiting for lo to become free. Usage count = 2Fix the dst leak by removing the dst_hold() in ip6_negative_advice(). Thepatch that introduced the dst_hold() in ip6_negative_advice() was92f1655aa2b22 ("net: fix __dst_negative_advice() race"). But 92f1655aa2b22merely refactored the code with regards to the dst refcount so the issuewas present even before 92f1655aa2b22. The bug was introduced in54c1a859efd9f ("ipv6: Don't drop cache route entry unless timer actuallyexpired.") where the expired cached route is deleted and the sk_dst_cachemember of the socket is set to NULL by calling dst_negative_advice() butthe refcount belonging to the socket is left unbalanced.The IPv4 version - ipv4_negative_advice() - is not affected by this bug.When the TCP connection times out ipv4_negative_advice() merely resets thesk_dst_cache of the socket while decrementing the refcount of theexception dst.|
|已分析|2.openEulerScore|2.5|
|已分析|3.openEulerVector|AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L|
|已分析|4.受影响版本排查|openEuler-20.03-LTS-SP4:受影响,openEuler-22.03-LTS-SP3:受影响,openEuler-22.03-LTS-SP4:受影响,openEuler-24.03-LTS:受影响,openEuler-24.03-LTS-SP1:受影响,master:不受影响,openEuler-24.03-LTS-Next:不受影响|
|已分析|5.是否涉及abi变化|openEuler-20.03-LTS-SP4:否,openEuler-22.03-LTS-SP3:否,master:否,openEuler-24.03-LTS:否,openEuler-24.03-LTS-Next:否,openEuler-22.03-LTS-SP4:否,openEuler-24.03-LTS-SP1:否|
|已分析|6.原因说明|openEuler-24.03-LTS:正常修复,openEuler-24.03-LTS-SP1:正常修复,openEuler-20.03-LTS-SP4:不修复-超出修复范围,openEuler-22.03-LTS-SP3:不修复-超出修复范围,openEuler-22.03-LTS-SP4:不修复-超出修复范围,master:不受影响-漏洞代码不能被攻击者触发,openEuler-24.03-LTS-Next:不受影响-漏洞代码不能被攻击者触发|

**请确认分析内容的准确性, 确认无误后, 您可以进行后续步骤, 否则您可以继续分析.**

CVE-2024-56644

影响性分析说明：
In the Linux kernel, the following vulnerability has been resolved:

net/ipv6: release expired exception dst cached in socket

Dst objects get leaked in ip6_negative_advice() when this function is
executed for an expired IPv6 route located in the exception table. There
are several conditions that must be fulfilled for the leak to occur:
* an ICMPv6 packet indicating a change of the MTU for the path is received,
  resulting in an exception dst being created
* a TCP connection that uses the exception dst for routing packets must
  start timing out so that TCP begins retransmissions
* after the exception dst expires, the FIB6 garbage collector must not run
  before TCP executes ip6_negative_advice() for the expired exception dst

When TCP executes ip6_negative_advice() for an exception dst that has
expired and if no other socket holds a reference to the exception dst, the
refcount of the exception dst is 2, which corresponds to the increment
made by dst_init() and the increment made by the TCP socket for which the
connection is timing out. The refcount made by the socket is never
released. The refcount of the dst is decremented in sk_dst_reset() but
that decrement is counteracted by a dst_hold() intentionally placed just
before the sk_dst_reset() in ip6_negative_advice(). After
ip6_negative_advice() has finished, there is no other object tied to the
dst. The socket lost its reference stored in sk_dst_cache and the dst is
no longer in the exception table. The exception dst becomes a leaked
object.

As a result of this dst leak, an unbalanced refcount is reported for the
loopback device of a net namespace being destroyed under kernels that do
not contain e5f80fcf869a (&#34;ipv6: give an IPv6 dev to blackhole_netdev&#34;):
unregister_netdevice: waiting for lo to become free. Usage count = 2

Fix the dst leak by removing the dst_hold() in ip6_negative_advice(). The
patch that introduced the dst_hold() in ip6_negative_advice() was
92f1655aa2b22 (&#34;net: fix __dst_negative_advice() race&#34;). But 92f1655aa2b22
merely refactored the code with regards to the dst refcount so the issue
was present even before 92f1655aa2b22. The bug was introduced in
54c1a859efd9f (&#34;ipv6: Don&#39;t drop cache route entry unless timer actually
expired.&#34;) where the expired cached route is deleted and the sk_dst_cache
member of the socket is set to NULL by calling dst_negative_advice() but
the refcount belonging to the socket is left unbalanced.

The IPv4 version - ipv4_negative_advice() - is not affected by this bug.
When the TCP connection times out ipv4_negative_advice() merely resets the
sk_dst_cache of the socket while decrementing the refcount of the
exception dst.

The Linux kernel CVE team has assigned CVE-2024-56644 to this issue.

openEuler评分:(评分和向量)
2.5
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L

受影响版本排查(受影响/不受影响):
1.master(6.1.0):不受影响
2.openEuler-20.03-LTS-SP4:受影响
3.openEuler-22.03-LTS-SP3:受影响
4.openEuler-22.03-LTS-SP4:受影响
5.openEuler-24.03-LTS:受影响
6.openEuler-24.03-LTS-Next:不受影响
7.openEuler-24.03-LTS-SP1:受影响

修复是否涉及abi变化(是/否)：
1.master(6.1.0):否
2.openEuler-20.03-LTS-SP4:否
3.openEuler-22.03-LTS-SP3:否
4.openEuler-22.03-LTS-SP4:否
5.openEuler-24.03-LTS:否
6.openEuler-24.03-LTS-Next:否
7.openEuler-24.03-LTS-SP1:否

原因说明：
1.master(23.08.5):不受影响-漏洞代码不能被攻击者触发
2.openEuler-20.03-LTS-SP4:不修复-超出修复范围
4.openEuler-22.03-LTS-SP3:不修复-超出修复范围
5.openEuler-22.03-LTS-SP4:不修复-超出修复范围
6.openEuler-24.03-LTS:正常修复
7.openEuler-24.03-LTS-Next:不受影响-漏洞代码不能被攻击者触发
8.openEuler-24.03-LTS-SP1:正常修复

@sanglipeng 经过 cve-manager 解析, 已分析的内容如下表所示:
| 状态  | 分析项目 | 内容 |
|:--:|:--:|---------|
|已分析|1.影响性分析说明|In the Linux kernel, the following vulnerability has been resolved:net/ipv6: release expired exception dst cached in socketDst objects get leaked in ip6_negative_advice() when this function isexecuted for an expired IPv6 route located in the exception table. Thereare several conditions that must be fulfilled for the leak to occur:* an ICMPv6 packet indicating a change of the MTU for the path is received,  resulting in an exception dst being created* a TCP connection that uses the exception dst for routing packets must  start timing out so that TCP begins retransmissions* after the exception dst expires, the FIB6 garbage collector must not run  before TCP executes ip6_negative_advice() for the expired exception dstWhen TCP executes ip6_negative_advice() for an exception dst that hasexpired and if no other socket holds a reference to the exception dst, therefcount of the exception dst is 2, which corresponds to the incrementmade by dst_init() and the increment made by the TCP socket for which theconnection is timing out. The refcount made by the socket is neverreleased. The refcount of the dst is decremented in sk_dst_reset() butthat decrement is counteracted by a dst_hold() intentionally placed justbefore the sk_dst_reset() in ip6_negative_advice(). Afterip6_negative_advice() has finished, there is no other object tied to thedst. The socket lost its reference stored in sk_dst_cache and the dst isno longer in the exception table. The exception dst becomes a leakedobject.As a result of this dst leak, an unbalanced refcount is reported for theloopback device of a net namespace being destroyed under kernels that donot contain e5f80fcf869a (&#34;ipv6: give an IPv6 dev to blackhole_netdev&#34;):unregister_netdevice: waiting for lo to become free. Usage count = 2Fix the dst leak by removing the dst_hold() in ip6_negative_advice(). Thepatch that introduced the dst_hold() in ip6_negative_advice() was92f1655aa2b22 (&#34;net: fix __dst_negative_advice() race&#34;). But 92f1655aa2b22merely refactored the code with regards to the dst refcount so the issuewas present even before 92f1655aa2b22. The bug was introduced in54c1a859efd9f (&#34;ipv6: Don&#39;t drop cache route entry unless timer actuallyexpired.&#34;) where the expired cached route is deleted and the sk_dst_cachemember of the socket is set to NULL by calling dst_negative_advice() butthe refcount belonging to the socket is left unbalanced.The IPv4 version - ipv4_negative_advice() - is not affected by this bug.When the TCP connection times out ipv4_negative_advice() merely resets thesk_dst_cache of the socket while decrementing the refcount of theexception dst.The Linux kernel CVE team has assigned CVE-2024-56644 to this issue.|
|已分析|2.openEulerScore|2.5|
|已分析|3.openEulerVector|AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L|
|已分析|4.受影响版本排查|openEuler-20.03-LTS-SP4:受影响,openEuler-22.03-LTS-SP3:受影响,openEuler-22.03-LTS-SP4:受影响,openEuler-24.03-LTS:受影响,openEuler-24.03-LTS-SP1:受影响,master:不受影响,openEuler-24.03-LTS-Next:不受影响|
|已分析|5.是否涉及abi变化|master:否,openEuler-20.03-LTS-SP4:否,openEuler-22.03-LTS-SP3:否,openEuler-22.03-LTS-SP4:否,openEuler-24.03-LTS:否,openEuler-24.03-LTS-Next:否,openEuler-24.03-LTS-SP1:否|
|已分析|6.原因说明|openEuler-24.03-LTS:正常修复,openEuler-24.03-LTS-SP1:正常修复,openEuler-20.03-LTS-SP4:不修复-超出修复范围,openEuler-22.03-LTS-SP3:不修复-超出修复范围,openEuler-22.03-LTS-SP4:不修复-超出修复范围,master:不受影响-漏洞代码不能被攻击者触发,openEuler-24.03-LTS-Next:不受影响-漏洞代码不能被攻击者触发|

**请确认分析内容的准确性, 确认无误后, 您可以进行后续步骤, 否则您可以继续分析.**

@sanglipeng 经过 cve-manager 解析, 已分析的内容如下表所示:
| 状态  | 分析项目 | 内容 |
|:--:|:--:|---------|
|已分析|1.影响性分析说明|In the Linux kernel, the following vulnerability has been resolved:net/ipv6: release expired exception dst cached in socketDst objects get leaked in ip6_negative_advice() when this function isexecuted for an expired IPv6 route located in the exception table. Thereare several conditions that must be fulfilled for the leak to occur:* an ICMPv6 packet indicating a change of the MTU for the path is received,  resulting in an exception dst being created* a TCP connection that uses the exception dst for routing packets must  start timing out so that TCP begins retransmissions* after the exception dst expires, the FIB6 garbage collector must not run  before TCP executes ip6_negative_advice() for the expired exception dstWhen TCP executes ip6_negative_advice() for an exception dst that hasexpired and if no other socket holds a reference to the exception dst, therefcount of the exception dst is 2, which corresponds to the incrementmade by dst_init() and the increment made by the TCP socket for which theconnection is timing out. The refcount made by the socket is neverreleased. The refcount of the dst is decremented in sk_dst_reset() butthat decrement is counteracted by a dst_hold() intentionally placed justbefore the sk_dst_reset() in ip6_negative_advice(). Afterip6_negative_advice() has finished, there is no other object tied to thedst. The socket lost its reference stored in sk_dst_cache and the dst isno longer in the exception table. The exception dst becomes a leakedobject.As a result of this dst leak, an unbalanced refcount is reported for theloopback device of a net namespace being destroyed under kernels that donot contain e5f80fcf869a (&#34;ipv6: give an IPv6 dev to blackhole_netdev&#34;):unregister_netdevice: waiting for lo to become free. Usage count = 2Fix the dst leak by removing the dst_hold() in ip6_negative_advice(). Thepatch that introduced the dst_hold() in ip6_negative_advice() was92f1655aa2b22 (&#34;net: fix __dst_negative_advice() race&#34;). But 92f1655aa2b22merely refactored the code with regards to the dst refcount so the issuewas present even before 92f1655aa2b22. The bug was introduced in54c1a859efd9f (&#34;ipv6: Don&#39;t drop cache route entry unless timer actuallyexpired.&#34;) where the expired cached route is deleted and the sk_dst_cachemember of the socket is set to NULL by calling dst_negative_advice() butthe refcount belonging to the socket is left unbalanced.The IPv4 version - ipv4_negative_advice() - is not affected by this bug.When the TCP connection times out ipv4_negative_advice() merely resets thesk_dst_cache of the socket while decrementing the refcount of theexception dst.The Linux kernel CVE team has assigned CVE-2024-56644 to this issue.|
|已分析|2.openEulerScore|2.5|
|已分析|3.openEulerVector|AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L|
|已分析|4.受影响版本排查|openEuler-20.03-LTS-SP4:受影响,openEuler-22.03-LTS-SP3:受影响,openEuler-22.03-LTS-SP4:受影响,openEuler-24.03-LTS:受影响,openEuler-24.03-LTS-SP1:受影响,master:不受影响,openEuler-24.03-LTS-Next:不受影响|
|已分析|5.是否涉及abi变化|master:否,openEuler-20.03-LTS-SP4:否,openEuler-22.03-LTS-SP3:否,openEuler-22.03-LTS-SP4:否,openEuler-24.03-LTS:否,openEuler-24.03-LTS-Next:否,openEuler-24.03-LTS-SP1:否|
|已分析|6.原因说明|openEuler-24.03-LTS:正常修复,openEuler-24.03-LTS-SP1:正常修复,openEuler-20.03-LTS-SP4:不修复-超出修复范围,openEuler-22.03-LTS-SP3:不修复-超出修复范围,openEuler-22.03-LTS-SP4:不修复-超出修复范围,master:不受影响-漏洞代码不能被攻击者触发,openEuler-24.03-LTS-Next:不受影响-漏洞代码不能被攻击者触发|

**请确认分析内容的准确性, 确认无误后, 您可以进行后续步骤, 否则您可以继续分析.**

CVE-2024-56644

影响性分析说明：
In the Linux kernel, the following vulnerability has been resolved:

net/ipv6: release expired exception dst cached in socket

Dst objects get leaked in ip6_negative_advice() when this function is
executed for an expired IPv6 route located in the exception table. There
are several conditions that must be fulfilled for the leak to occur:
* an ICMPv6 packet indicating a change of the MTU for the path is received,
  resulting in an exception dst being created
* a TCP connection that uses the exception dst for routing packets must
  start timing out so that TCP begins retransmissions
* after the exception dst expires, the FIB6 garbage collector must not run
  before TCP executes ip6_negative_advice() for the expired exception dst

When TCP executes ip6_negative_advice() for an exception dst that has
expired and if no other socket holds a reference to the exception dst, the
refcount of the exception dst is 2, which corresponds to the increment
made by dst_init() and the increment made by the TCP socket for which the
connection is timing out. The refcount made by the socket is never
released. The refcount of the dst is decremented in sk_dst_reset() but
that decrement is counteracted by a dst_hold() intentionally placed just
before the sk_dst_reset() in ip6_negative_advice(). After
ip6_negative_advice() has finished, there is no other object tied to the
dst. The socket lost its reference stored in sk_dst_cache and the dst is
no longer in the exception table. The exception dst becomes a leaked
object.

As a result of this dst leak, an unbalanced refcount is reported for the
loopback device of a net namespace being destroyed under kernels that do
not contain e5f80fcf869a ("ipv6: give an IPv6 dev to blackhole_netdev"):
unregister_netdevice: waiting for lo to become free. Usage count = 2

Fix the dst leak by removing the dst_hold() in ip6_negative_advice(). The
patch that introduced the dst_hold() in ip6_negative_advice() was
92f1655aa2b22 ("net: fix __dst_negative_advice() race"). But 92f1655aa2b22
merely refactored the code with regards to the dst refcount so the issue
was present even before 92f1655aa2b22. The bug was introduced in
54c1a859efd9f ("ipv6: Don't drop cache route entry unless timer actually
expired.") where the expired cached route is deleted and the sk_dst_cache
member of the socket is set to NULL by calling dst_negative_advice() but
the refcount belonging to the socket is left unbalanced.

The IPv4 version - ipv4_negative_advice() - is not affected by this bug.
When the TCP connection times out ipv4_negative_advice() merely resets the
sk_dst_cache of the socket while decrementing the refcount of the
exception dst.

openEuler评分:(评分和向量)
2.5
CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L