perf cpumap: Fix writing to illegal memory in handling cpumap mask

cpu_map__snprint_mask() would write to illegal memory pointed by
zalloc(0) when there is only one cpu.

This patch fixes the calculation and adds sanity check against the input
parameters.

Signed-off-by: He Zhe <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Alexey Budankov <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Fixes: 4400ac8a9a90 ("perf cpumap: Introduce cpu_map__snprint_mask()")
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

0 files changed, 0 insertions, 0 deletions