CVE-2026-90057

Summary

In the Linux kernel, the following vulnerability has been resolved:

slip: remove slip_hangup() to fix use-after-free in slip_receive_buf()

Jaeyoung Chung and Eulgyu Kim reported a slab-use-after-free read in slip_receive_buf() when racing against tty hangup.

tty_ldisc_hangup() calls ld->ops->hangup() while holding only a read lock on tty->ldisc_sem (via tty_ldisc_ref()). Because slip_hangup() simply called slip_close(), it ran concurrently with reader functions such as slip_receive_buf().

slip_close() unregisters and frees the net device and its private struct slip, causing concurrent reader threads in slip_receive_buf() to dereference freed memory.

Line discipline close() is already guaranteed to be called under the write lock of tty->ldisc_sem during hangup processing (in tty_ldisc_reinit() or tty_ldisc_kill()).

Remove slip_hangup() so teardown is serialized cleanly by slip_close().

Affected Software

VendorProductVersion RangeStatus
LinuxLinux5342b77c4123ba39f911d92a813295fb3bb21f69 < 9a3b1edff1ecb47d323f2506b3ffc22178acd1c6affected
LinuxLinux5342b77c4123ba39f911d92a813295fb3bb21f69 < a2dbac3fb03b4427ccf057debc83fc61ee102529affected
LinuxLinux5342b77c4123ba39f911d92a813295fb3bb21f69 < de1f978c0f6ab42b28192d74dc59af52fdc76135affected
LinuxLinux5342b77c4123ba39f911d92a813295fb3bb21f69 < ddbc5dc5a2e29b3934da09c1ba3c930fd8a40fd6affected
LinuxLinux5342b77c4123ba39f911d92a813295fb3bb21f69 < a540a49fcca59d1c92c3a6462e67ca21676a88dfaffected
LinuxLinux5342b77c4123ba39f911d92a813295fb3bb21f69 < 23c53269f2baaedf2d92784290cb9ef6db2a3bceaffected
LinuxLinux2.6.32affected
LinuxLinux0 < 2.6.32unaffected
LinuxLinux6.1.188 <= 6.1.*unaffected
LinuxLinux6.6.157 <= 6.6.*unaffected
LinuxLinux6.12.110 <= 6.12.*unaffected
LinuxLinux6.18.52 <= 6.18.*unaffected
LinuxLinux7.2.6 <= 7.2.*unaffected
LinuxLinux7.3-rc1 <= *unaffected

Weaknesses

References