From 3d8fa456d5ed22ce8db085a89a037b87568b2b64 Mon Sep 17 00:00:00 2001 From: Peter Hurley Date: Tue, 30 Apr 2013 19:14:25 -0700 Subject: ipc: clamp with min() Signed-off-by: Peter Hurley Acked-by: Stanislav Kinsbursky Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- ipc/msgutil.c | 30 ++++++++---------------------- 1 file changed, 8 insertions(+), 22 deletions(-) (limited to 'ipc/msgutil.c') diff --git a/ipc/msgutil.c b/ipc/msgutil.c index 5df8e4bf1db0..98b1c2b476cc 100644 --- a/ipc/msgutil.c +++ b/ipc/msgutil.c @@ -41,8 +41,8 @@ struct msg_msgseg { /* the next part of the message follows immediately */ }; -#define DATALEN_MSG (PAGE_SIZE-sizeof(struct msg_msg)) -#define DATALEN_SEG (PAGE_SIZE-sizeof(struct msg_msgseg)) +#define DATALEN_MSG (int)(PAGE_SIZE-sizeof(struct msg_msg)) +#define DATALEN_SEG (int)(PAGE_SIZE-sizeof(struct msg_msgseg)) struct msg_msg *load_msg(const void __user *src, int len) { @@ -51,10 +51,7 @@ struct msg_msg *load_msg(const void __user *src, int len) int err; int alen; - alen = len; - if (alen > DATALEN_MSG) - alen = DATALEN_MSG; - + alen = min(len, DATALEN_MSG); msg = kmalloc(sizeof(*msg) + alen, GFP_KERNEL); if (msg == NULL) return ERR_PTR(-ENOMEM); @@ -72,9 +69,7 @@ struct msg_msg *load_msg(const void __user *src, int len) pseg = &msg->next; while (len > 0) { struct msg_msgseg *seg; - alen = len; - if (alen > DATALEN_SEG) - alen = DATALEN_SEG; + alen = min(len, DATALEN_SEG); seg = kmalloc(sizeof(*seg) + alen, GFP_KERNEL); if (seg == NULL) { @@ -113,19 +108,14 @@ struct msg_msg *copy_msg(struct msg_msg *src, struct msg_msg *dst) if (src->m_ts > dst->m_ts) return ERR_PTR(-EINVAL); - alen = len; - if (alen > DATALEN_MSG) - alen = DATALEN_MSG; - + alen = min(len, DATALEN_MSG); memcpy(dst + 1, src + 1, alen); len -= alen; dst_pseg = dst->next; src_pseg = src->next; while (len > 0) { - alen = len; - if (alen > DATALEN_SEG) - alen = DATALEN_SEG; + alen = min(len, DATALEN_SEG); memcpy(dst_pseg + 1, src_pseg + 1, alen); dst_pseg = dst_pseg->next; len -= alen; @@ -148,9 +138,7 @@ int store_msg(void __user *dest, struct msg_msg *msg, int len) int alen; struct msg_msgseg *seg; - alen = len; - if (alen > DATALEN_MSG) - alen = DATALEN_MSG; + alen = min(len, DATALEN_MSG); if (copy_to_user(dest, msg + 1, alen)) return -1; @@ -158,9 +146,7 @@ int store_msg(void __user *dest, struct msg_msg *msg, int len) dest = ((char __user *)dest) + alen; seg = msg->next; while (len > 0) { - alen = len; - if (alen > DATALEN_SEG) - alen = DATALEN_SEG; + alen = min(len, DATALEN_SEG); if (copy_to_user(dest, seg + 1, alen)) return -1; len -= alen; -- cgit v1.2.3-59-g8ed1b