Commit e79ce983 authored by Liu Yuntao's avatar Liu Yuntao Committed by Linus Torvalds
Browse files

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@huawei.com


Fixes: b5389086 ("hugetlbfs: extend the definition of hugepages parameter to support node allocation")
Signed-off-by: default avatarLiu Yuntao <liuyuntao10@huawei.com>
Reviewed-by: default avatarMike Kravetz <mike.kravetz@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 70effdc3

mm/hugetlb.c

+2 −2
Original line number Diff line number Diff line
@@ -4159,10 +4159,10 @@ static int __init hugepages_setup(char *s) 
				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;