UBUNTU-CVE-2026-90057: Use After Free
In the Linux kernel, the following vulnerability has been resolved: slip: remove sliphangup() to fix use-after-free in slipreceivebuf() Jaeyoung Chung and Eulgyu Kim reported a slab-use-after-free read in slipreceivebuf() when racing against tty hangup. ttyldischangup() calls ld->ops->hangup() while holding only a read lock on tty->ldiscsem (via ttyldiscref()). Because sliphangup() simply called slipclose(), it ran concurrently with reader functions such as slipreceivebuf(). slipclose() unregisters and frees the net device and its private struct slip, causing concurrent reader threads in slipreceivebuf() to dereference freed memory. Line discipline close() is already guaranteed to be called under the write lock of tty->ldiscsem during hangup processing (in ttyldiscreinit() or ttyldisckill()). Remove sliphangup() so teardown is serialized cleanly by slipclose().
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
ubuntu/linux-hwe-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-42.42~24.04.1 - Upgrade
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ubuntu/linux-riscv-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-42.42.1~24.04.1 - Upgrade
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ubuntu/linuxto a version that resolves this vulnerability.Fixed in 7.0.0-42.42 - Upgrade
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ubuntu/linux-awsto a version that resolves this vulnerability.Fixed in 7.0.0-1016.17 - Upgrade
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ubuntu/linux-gcpto a version that resolves this vulnerability.Fixed in 7.0.0-1016.18 - Upgrade
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ubuntu/linux-ibmto a version that resolves this vulnerability.Fixed in 7.0.0-1017.17 - Upgrade
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ubuntu/linux-oem-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1017.17 - Upgrade
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ubuntu/linux-oracleto a version that resolves this vulnerability.Fixed in 7.0.0-1015.16 - Upgrade
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ubuntu/linux-riscvto a version that resolves this vulnerability.Fixed in 7.0.0-42.42.1