From 64ce1037c5434b1d036cd99ecaee6e00496bc2e9 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Fri, 15 Jan 2010 17:01:15 -0800 Subject: kfifo: sanitize *_user error handling Right now for kfifo_*_user it's not easily possible to distingush between a user copy failing and the FIFO not containing enough data. The problem is that both conditions are multiplexed into the same return code. Avoid this by moving the "copy length" into a separate output parameter and only return 0/-EFAULT in the main return value. I didn't fully adapt the weird "record" variants, those seem to be unused anyways and were rather messy (should they be just removed?) I would appreciate some double checking if I did all the conversions correctly. Signed-off-by: Andi Kleen Cc: Stefani Seibold Cc: Roland Dreier Cc: Dmitry Torokhov Cc: Andy Walls Cc: Vikram Dhillon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/kfifo.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'include') diff --git a/include/linux/kfifo.h b/include/linux/kfifo.h index 6fb495ea956..86ad50a900c 100644 --- a/include/linux/kfifo.h +++ b/include/linux/kfifo.h @@ -235,11 +235,11 @@ static inline __must_check unsigned int kfifo_out_locked(struct kfifo *fifo, extern void kfifo_skip(struct kfifo *fifo, unsigned int len); -extern __must_check unsigned int kfifo_from_user(struct kfifo *fifo, - const void __user *from, unsigned int n); +extern __must_check int kfifo_from_user(struct kfifo *fifo, + const void __user *from, unsigned int n, unsigned *lenout); -extern __must_check unsigned int kfifo_to_user(struct kfifo *fifo, - void __user *to, unsigned int n); +extern __must_check int kfifo_to_user(struct kfifo *fifo, + void __user *to, unsigned int n, unsigned *lenout); /* * __kfifo_add_out internal helper function for updating the out offset -- cgit v1.2.3