In the Linux kernel, the following vulnerability has been resolved:
sctp: linearize cloned gso packets in sctp_rcv
A cloned head skb still shares these frag skbs in fraglist with the
original head skb. It's not safe to access these frag skbs.
syzbot reported two use-of-uninitialized-memory bugs caused by this:
BUG: KMSAN: uninit-value in sctp_inq_pop+0x15b7/0x1920 net/sctp/inqueue.c:211
sctp_inq_pop+0x15b7/0x1920 net/sctp/inqueue.c:211
sctp_assoc_bh_rcv+0x1a7/0xc50 net/sctp/associola.c:998
sctp_inq_push+0x2ef/0x380 net/sctp/inqueue.c:88
sctp_backlog_rcv+0x397/0xdb0 net/sctp/input.c:331
sk_backlog_rcv+0x13b/0x420 include/net/sock.h:1122
__release_sock+0x1da/0x330 net/core/sock.c:3106
release_sock+0x6b/0x250 net/core/sock.c:3660
sctp_wait_for_connect+0x487/0x820 net/sctp/socket.c:9360
sctp_sendmsg_to_asoc+0x1ec1/0x1f00 net/sctp/socket.c:1885
sctp_sendmsg+0x32b9/0x4a80 net/sctp/socket.c:2031
inet_sendmsg+0x25a/0x280 net/ipv4/af_inet.c:851
sock_sendmsg_nosec net/socket.c:718 [inline]
and
BUG: KMSAN: uninit-value in sctp_assoc_bh_rcv+0x34e/0xbc0 net/sctp/associola.c:987
sctp_assoc_bh_rcv+0x34e/0xbc0 net/sctp/associola.c:987
sctp_inq_push+0x2a3/0x350 net/sctp/inqueue.c:88
sctp_backlog_rcv+0x3c7/0xda0 net/sctp/input.c:331
sk_backlog_rcv+0x142/0x420 include/net/sock.h:1148
__release_sock+0x1d3/0x330 net/core/sock.c:3213
release_sock+0x6b/0x270 net/core/sock.c:3767
sctp_wait_for_connect+0x458/0x820 net/sctp/socket.c:9367
sctp_sendmsg_to_asoc+0x223a/0x2260 net/sctp/socket.c:1886
sctp_sendmsg+0x3910/0x49f0 net/sctp/socket.c:2032
inet_sendmsg+0x269/0x2a0 net/ipv4/af_inet.c:851
sock_sendmsg_nosec net/socket.c:712 [inline]
This patch fixes it by linearizing cloned gso packets in sctp_rcv().
sctp: linearize cloned gso packets in sctp_rcv
A cloned head skb still shares these frag skbs in fraglist with the
original head skb. It's not safe to access these frag skbs.
syzbot reported two use-of-uninitialized-memory bugs caused by this:
BUG: KMSAN: uninit-value in sctp_inq_pop+0x15b7/0x1920 net/sctp/inqueue.c:211
sctp_inq_pop+0x15b7/0x1920 net/sctp/inqueue.c:211
sctp_assoc_bh_rcv+0x1a7/0xc50 net/sctp/associola.c:998
sctp_inq_push+0x2ef/0x380 net/sctp/inqueue.c:88
sctp_backlog_rcv+0x397/0xdb0 net/sctp/input.c:331
sk_backlog_rcv+0x13b/0x420 include/net/sock.h:1122
__release_sock+0x1da/0x330 net/core/sock.c:3106
release_sock+0x6b/0x250 net/core/sock.c:3660
sctp_wait_for_connect+0x487/0x820 net/sctp/socket.c:9360
sctp_sendmsg_to_asoc+0x1ec1/0x1f00 net/sctp/socket.c:1885
sctp_sendmsg+0x32b9/0x4a80 net/sctp/socket.c:2031
inet_sendmsg+0x25a/0x280 net/ipv4/af_inet.c:851
sock_sendmsg_nosec net/socket.c:718 [inline]
and
BUG: KMSAN: uninit-value in sctp_assoc_bh_rcv+0x34e/0xbc0 net/sctp/associola.c:987
sctp_assoc_bh_rcv+0x34e/0xbc0 net/sctp/associola.c:987
sctp_inq_push+0x2a3/0x350 net/sctp/inqueue.c:88
sctp_backlog_rcv+0x3c7/0xda0 net/sctp/input.c:331
sk_backlog_rcv+0x142/0x420 include/net/sock.h:1148
__release_sock+0x1d3/0x330 net/core/sock.c:3213
release_sock+0x6b/0x270 net/core/sock.c:3767
sctp_wait_for_connect+0x458/0x820 net/sctp/socket.c:9367
sctp_sendmsg_to_asoc+0x223a/0x2260 net/sctp/socket.c:1886
sctp_sendmsg+0x3910/0x49f0 net/sctp/socket.c:2032
inet_sendmsg+0x269/0x2a0 net/ipv4/af_inet.c:851
sock_sendmsg_nosec net/socket.c:712 [inline]
This patch fixes it by linearizing cloned gso packets in sctp_rcv().
Metrics
Affected Vendors & Products
References
History
Fri, 05 Sep 2025 14:15:00 +0000
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Linux
Linux linux Kernel |
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Vendors & Products |
Linux
Linux linux Kernel |
Fri, 05 Sep 2025 00:15:00 +0000
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References |
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Metrics |
threat_severity
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cvssV3_1
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Thu, 04 Sep 2025 15:45:00 +0000
Type | Values Removed | Values Added |
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Description | In the Linux kernel, the following vulnerability has been resolved: sctp: linearize cloned gso packets in sctp_rcv A cloned head skb still shares these frag skbs in fraglist with the original head skb. It's not safe to access these frag skbs. syzbot reported two use-of-uninitialized-memory bugs caused by this: BUG: KMSAN: uninit-value in sctp_inq_pop+0x15b7/0x1920 net/sctp/inqueue.c:211 sctp_inq_pop+0x15b7/0x1920 net/sctp/inqueue.c:211 sctp_assoc_bh_rcv+0x1a7/0xc50 net/sctp/associola.c:998 sctp_inq_push+0x2ef/0x380 net/sctp/inqueue.c:88 sctp_backlog_rcv+0x397/0xdb0 net/sctp/input.c:331 sk_backlog_rcv+0x13b/0x420 include/net/sock.h:1122 __release_sock+0x1da/0x330 net/core/sock.c:3106 release_sock+0x6b/0x250 net/core/sock.c:3660 sctp_wait_for_connect+0x487/0x820 net/sctp/socket.c:9360 sctp_sendmsg_to_asoc+0x1ec1/0x1f00 net/sctp/socket.c:1885 sctp_sendmsg+0x32b9/0x4a80 net/sctp/socket.c:2031 inet_sendmsg+0x25a/0x280 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:718 [inline] and BUG: KMSAN: uninit-value in sctp_assoc_bh_rcv+0x34e/0xbc0 net/sctp/associola.c:987 sctp_assoc_bh_rcv+0x34e/0xbc0 net/sctp/associola.c:987 sctp_inq_push+0x2a3/0x350 net/sctp/inqueue.c:88 sctp_backlog_rcv+0x3c7/0xda0 net/sctp/input.c:331 sk_backlog_rcv+0x142/0x420 include/net/sock.h:1148 __release_sock+0x1d3/0x330 net/core/sock.c:3213 release_sock+0x6b/0x270 net/core/sock.c:3767 sctp_wait_for_connect+0x458/0x820 net/sctp/socket.c:9367 sctp_sendmsg_to_asoc+0x223a/0x2260 net/sctp/socket.c:1886 sctp_sendmsg+0x3910/0x49f0 net/sctp/socket.c:2032 inet_sendmsg+0x269/0x2a0 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:712 [inline] This patch fixes it by linearizing cloned gso packets in sctp_rcv(). | |
Title | sctp: linearize cloned gso packets in sctp_rcv | |
References |
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Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2025-09-04T15:33:12.448Z
Reserved: 2025-04-16T04:51:24.033Z
Link: CVE-2025-38718

No data.

Status : Awaiting Analysis
Published: 2025-09-04T16:15:41.413
Modified: 2025-09-05T17:47:24.833
Link: CVE-2025-38718


Updated: 2025-09-05T14:02:35Z