Memory leak in the sas_smp_get_phy_events function in drivers/scsi/libsas/sas_expander.c in the Linux kernel through 4.15.7 allows local users to cause a denial of service (memory consumption) via many read accesses to files in the /sys/class/sas_phy directory, as demonstrated by the /sys/class/sas_phy/phy-1:0:12/invalid_dword_count file.