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In the Linux kernel, the following vulnerability has been resolved: smb: client: fix overflow in passthrough ioctl bounds check smb2_ioctl_query_info() validates the PASSTHRU_FSCTL response payload before copying it to userspace. The payload offset and length both come from 32-bit fields. The bounds check currently adds OutputOffset and qi.input_buffer_length directly, so the addition can wrap in 32-bit arithmetic before the result is compared against the response buffer length. A malicious server can use a large OutputOffset and a small OutputCount to make the wrapped sum pass the bounds check. The later copy_to_user() then reads from io_rsp + OutputOffset, outside the response buffer. Use size_add() for the offset plus length check so overflow is treated as out of bounds.
Upstream advisory: https://lore.kernel.org/linux-cve-announce/2026081504-CVE-2026-72310-7e47@gregkh/T