CVEvulnerability
CVE-2026-89552
- Status
- Received
- Published
- 2026-09-11
- Last modified
- 2026-10-21
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
params: fix charp corruption on allocation failure
param_set_charp() stores charp parameters in allocated memory after slab is
available, and releases the previous value when the parameter is updated.
The previous value is released before the replacement allocation succeeds.
If kmalloc_parameter() fails, the setter returns -ENOMEM with the parameter
left as NULL.
Failing zswap's compressor update before zswap is initialized can later
trigger:
BUG: kernel NULL pointer dereference, address: 0000000000000000
RIP: 0010:strcmp+0x10/0x30
Call Trace:
zswap_setup+0x3b1/0x490
zswap_enabled_param_set+0x5b/0xa0
param_attr_store+0x93/0xe0
module_attr_store+0x1c/0x30
kernfs_fop_write_iter+0x116/0x1f0
Allocate and copy the replacement first, then replace the parameter value
only after allocation succeeds.
References
- https://git.kernel.org/stable/c/0d8e2404925a0607ffec79a53170715a46936896 git.kernel.org
- https://git.kernel.org/stable/c/31b41ea8383d51992d6b0dfe3a99da1dec8ce1c1 git.kernel.org
- https://git.kernel.org/stable/c/3dfaae04243cde460d82dfc2a7dd0bb6664d20ae git.kernel.org
- https://git.kernel.org/stable/c/614f873268c5b172804c9af6639bd17b7e1e2359 git.kernel.org
- https://git.kernel.org/stable/c/704ecd010d4a9b33160e40b74eb402f6b86a18e0 git.kernel.org