CVE-2026-93186
Description
AI Translation Available
In the Linux kernel, the following vulnerability has been resolved:
cxl/mbox: Clamp mailbox output allocation to the payload size
CXL_MEM_SEND_COMMAND bounds the user's in.size to the mailbox payload
size but leaves out.size unbounded, then cxl_mbox_cmd_ctor() calls
kvzalloc(out.size). A large out.size drives a huge allocation, above
INT_MAX it WARNs and taints, and with panic_on_warn=1 it panics.
The transport __cxl_pci_mbox_send_cmd() already clamps the response copy
to min(out.size, payload_size, device len), so the output buffer is
never written beyond payload_size. Clamp the allocation to payload_size
too, matching the RAW path.
https://git.kernel.org/stable/c/31d4841eca7c4b75751ca96d24339e19303337f2
https://git.kernel.org/stable/c/8a13db9f899d149c3aab24abcb668121cfda5a4f
https://git.kernel.org/stable/c/b4e11c731d6bee3b87315e055a1ca417c92dc1fc
https://git.kernel.org/stable/c/f5d2bbf0300f46307948864fbb97bce5097f4fe2