Convert the unbound sprintf in hugetlb_report_node_meminfo to use sysfs_emit_at so that no possible overrun of a PAGE_SIZE buf can occur.
Signed-off-by: Joe Perches <[email protected]> --- drivers/base/node.c | 2 +- include/linux/hugetlb.h | 4 ++-- mm/hugetlb.c | 18 ++++++++++-------- 3 files changed, 13 insertions(+), 11 deletions(-) diff --git a/drivers/base/node.c b/drivers/base/node.c index b33526a9fcfc..dafe03e82e7c 100644 --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -473,7 +473,7 @@ static ssize_t node_read_meminfo(struct device *dev, HPAGE_PMD_NR) #endif ); - len += hugetlb_report_node_meminfo(nid, buf + len); + len += hugetlb_report_node_meminfo(buf, len, nid); return len; } diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index d5cc5f802dd4..ebca2ef02212 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -129,7 +129,7 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma, unsigned long start, unsigned long end, struct page *ref_page); void hugetlb_report_meminfo(struct seq_file *); -int hugetlb_report_node_meminfo(int, char *); +int hugetlb_report_node_meminfo(char *buf, int len, int nid); void hugetlb_show_meminfo(void); unsigned long hugetlb_total_pages(void); vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, @@ -245,7 +245,7 @@ static inline void hugetlb_report_meminfo(struct seq_file *m) { } -static inline int hugetlb_report_node_meminfo(int nid, char *buf) +static inline int hugetlb_report_node_meminfo(char *buf, int len, int nid) { return 0; } diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 61469fd3ad92..fe76f8fd5a73 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -3571,18 +3571,20 @@ void hugetlb_report_meminfo(struct seq_file *m) seq_printf(m, "Hugetlb: %8lu kB\n", total / 1024); } -int hugetlb_report_node_meminfo(int nid, char *buf) +int hugetlb_report_node_meminfo(char *buf, int len, int nid) { struct hstate *h = &default_hstate; + if (!hugepages_supported()) return 0; - return sprintf(buf, - "Node %d HugePages_Total: %5u\n" - "Node %d HugePages_Free: %5u\n" - "Node %d HugePages_Surp: %5u\n", - nid, h->nr_huge_pages_node[nid], - nid, h->free_huge_pages_node[nid], - nid, h->surplus_huge_pages_node[nid]); + + return sysfs_emit_at(buf, len, + "Node %d HugePages_Total: %5u\n" + "Node %d HugePages_Free: %5u\n" + "Node %d HugePages_Surp: %5u\n", + nid, h->nr_huge_pages_node[nid], + nid, h->free_huge_pages_node[nid], + nid, h->surplus_huge_pages_node[nid]); } void hugetlb_show_meminfo(void) -- 2.26.0
