Description
In the Linux kernel, the following vulnerability has been resolved: serial: caif: hold tty->link reference in ldisc_open and ser_release A reproducer triggers a KASAN slab-use-after-free in pty_write_room() when caif_serial's TX path calls tty_write_room(). The faulting access is on tty->link->port. Hold an extra kref on tty->link for the lifetime of the caif_serial line discipline: get it in ldisc_open() and drop it in ser_release(), and also drop it on the ldisc_open() error path. With this change applied, the reproducer no longer triggers the UAF in my testing.
Affected products
linux: linux kernel
References8
- git.kernel.org/stable/c/23a3ac2e2262a291498567418227b99e1f3606b1 Patch
- git.kernel.org/stable/c/27e43356d0defb9fc7fa25265219a3ffeb7b3e98 Patch
- git.kernel.org/stable/c/288598d80a068a0e9281de35bcb4ce495f189e2a Patch
- git.kernel.org/stable/c/35b58d3bc716ebb9ebd10fe1cac8c1177242511c Patch
- git.kernel.org/stable/c/52135420e9f75853ea0c6cea7b736e3e98495f7d Patch
- git.kernel.org/stable/c/8460187b4852fd00bd1c76394358053f3fa4d089 Patch
- git.kernel.org/stable/c/97a0bb491cae39478c6225381f14e9ac67b7bba7 Patch
- git.kernel.org/stable/c/ca2ceba983bb23ea0202c2882d963253416654a3 Patch
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 2 · as of 13 November 2026
- CWE
- CWE-416
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