From: Liu Yuntao <liuyuntao10@xxxxxxxxxx> Subject: hugetlbfs: fix a truncation issue in hugepages parameter When we specify a large number for node in hugepages parameter, it may be parsed to another number due to truncation in this statement: node = tmp; For example, add following parameter in command line: hugepagesz=1G hugepages=4294967297:5 and kernel will allocate 5 hugepages for node 1 instead of ignoring it. I move the validation check earlier to fix this issue, and slightly simplifies the condition here. Link: https://lkml.kernel.org/r/20220209134018.8242-1-liuyuntao10@xxxxxxxxxx Fixes: b5389086ad7be0 ("hugetlbfs: extend the definition of hugepages parameter to support node allocation") Signed-off-by: Liu Yuntao <liuyuntao10@xxxxxxxxxx> Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/hugetlb.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/mm/hugetlb.c~hugetlbfs-fix-a-truncation-issue-in-hugepages-parameter +++ a/mm/hugetlb.c @@ -4159,10 +4159,10 @@ static int __init hugepages_setup(char * pr_warn("HugeTLB: architecture can't support node specific alloc, ignoring!\n"); return 0; } + if (tmp >= nr_online_nodes) + goto invalid; node = tmp; p += count + 1; - if (node < 0 || node >= nr_online_nodes) - goto invalid; /* Parse hugepages */ if (sscanf(p, "%lu%n", &tmp, &count) != 1) goto invalid; _
