The (1) sparc_mmap_check function in arch/sparc/kernel/sys_sparc.c and the (2) sparc64_mmap_check function in arch/sparc64/kernel/sys_sparc.c, in the Linux kernel 2.4 before 2.4.36.5 and 2.6 before 2.6.25.3, omit some virtual-address range (aka span) checks when the mmap MAP_FIXED bit is not set, which allows local users to cause a denial of service (panic) via unspecified mmap calls.