In the Linux kernel, the following vulnerability has been resolved:
iscsiibft: Fix UBSAN shift-out-of-bounds warning in ibftattrshownic()
When performing an iSCSI boot using IPv6, iscsistart still reads the /sys/firmware/ibft/ethernetX/subnet-mask entry. Since the IPv6 prefix length is 64, this causes the shift exponent to become negative, triggering a UBSAN warning. As the concept of a subnet mask does not apply to IPv6, the value is set to ~0 to suppress the warning message.
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