From 32927393dc1ccd60fb2bdc05b9e8e88753761469 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 24 Apr 2020 08:43:38 +0200 Subject: sysctl: pass kernel pointers to ->proc_handler Instead of having all the sysctl handlers deal with user pointers, which is rather hairy in terms of the BPF interaction, copy the input to and from userspace in common code. This also means that the strings are always NUL-terminated by the common code, making the API a little bit safer. As most handler just pass through the data to one of the common handlers a lot of the changes are mechnical. Signed-off-by: Christoph Hellwig Acked-by: Andrey Ignatov Signed-off-by: Al Viro --- mm/hugetlb.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) (limited to 'mm/hugetlb.c') diff --git a/mm/hugetlb.c b/mm/hugetlb.c index cd459155d28a..2277c5728b1f 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -3352,7 +3352,7 @@ static unsigned int cpuset_mems_nr(unsigned int *array) #ifdef CONFIG_SYSCTL static int hugetlb_sysctl_handler_common(bool obey_mempolicy, struct ctl_table *table, int write, - void __user *buffer, size_t *length, loff_t *ppos) + void *buffer, size_t *length, loff_t *ppos) { struct hstate *h = &default_hstate; unsigned long tmp = h->max_huge_pages; @@ -3375,7 +3375,7 @@ out: } int hugetlb_sysctl_handler(struct ctl_table *table, int write, - void __user *buffer, size_t *length, loff_t *ppos) + void *buffer, size_t *length, loff_t *ppos) { return hugetlb_sysctl_handler_common(false, table, write, @@ -3384,7 +3384,7 @@ int hugetlb_sysctl_handler(struct ctl_table *table, int write, #ifdef CONFIG_NUMA int hugetlb_mempolicy_sysctl_handler(struct ctl_table *table, int write, - void __user *buffer, size_t *length, loff_t *ppos) + void *buffer, size_t *length, loff_t *ppos) { return hugetlb_sysctl_handler_common(true, table, write, buffer, length, ppos); @@ -3392,8 +3392,7 @@ int hugetlb_mempolicy_sysctl_handler(struct ctl_table *table, int write, #endif /* CONFIG_NUMA */ int hugetlb_overcommit_handler(struct ctl_table *table, int write, - void __user *buffer, - size_t *length, loff_t *ppos) + void *buffer, size_t *length, loff_t *ppos) { struct hstate *h = &default_hstate; unsigned long tmp; -- cgit v1.2.3-70-g09d2