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 --- include/linux/writeback.h | 28 +++++++++++----------------- 1 file changed, 11 insertions(+), 17 deletions(-) (limited to 'include/linux/writeback.h') diff --git a/include/linux/writeback.h b/include/linux/writeback.h index a19d845dd7eb..f8a7e1a850fb 100644 --- a/include/linux/writeback.h +++ b/include/linux/writeback.h @@ -362,24 +362,18 @@ extern int vm_highmem_is_dirtyable; extern int block_dump; extern int laptop_mode; -extern int dirty_background_ratio_handler(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, - loff_t *ppos); -extern int dirty_background_bytes_handler(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, - loff_t *ppos); -extern int dirty_ratio_handler(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, - loff_t *ppos); -extern int dirty_bytes_handler(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, - loff_t *ppos); +int dirty_background_ratio_handler(struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos); +int dirty_background_bytes_handler(struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos); +int dirty_ratio_handler(struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos); +int dirty_bytes_handler(struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos); int dirtytime_interval_handler(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos); - -struct ctl_table; -int dirty_writeback_centisecs_handler(struct ctl_table *, int, - void __user *, size_t *, loff_t *); + void *buffer, size_t *lenp, loff_t *ppos); +int dirty_writeback_centisecs_handler(struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos); void global_dirty_limits(unsigned long *pbackground, unsigned long *pdirty); unsigned long wb_calc_thresh(struct bdi_writeback *wb, unsigned long thresh); -- cgit v1.2.3-59-g8ed1b