From: Sylwester Nawrocki <s.nawrocki@samsung.com>
Date: Tue, 18 May 2021 12:56:13 +0000 (+0200)
Subject: kdbus: Remove unreachable code from kdbus_msg_examine
X-Git-Tag: submit/tizen/20210531.013858^0
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=d892d39588934e2372651128484509d5279fffce;p=platform%2Fkernel%2Flinux-rpi3.git

kdbus: Remove unreachable code from kdbus_msg_examine

This fixes an issue pointed out with SVACE warning:

* UNREACHABLE_CODE: This statement in the source code might be unreachable
  during program execution.
    [unreachable] unreachable at linux-rpi3/ipc/kdbus/message.c:346
    [vec_size > vec_size + size (0 > ANY) is always false] vec_size >
   vec_size + size (0 > ANY) is always false at linux-rpi3/ipc/kdbus/message.c:345

Change-Id: Ic154b2dbb0740f9e49b68ef273f19cd89e90c200
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
---

diff --git a/ipc/kdbus/message.c b/ipc/kdbus/message.c
index 17475a652d5c..406d57cba486 100644
--- a/ipc/kdbus/message.c
+++ b/ipc/kdbus/message.c
@@ -284,7 +284,7 @@ static int kdbus_msg_examine(struct kdbus_msg *msg, struct kdbus_bus *bus,
 			     size_t *out_n_fds, size_t *out_n_parts)
 {
 	struct kdbus_item *item, *fds = NULL, *bloom = NULL, *dstname = NULL;
-	u64 n_parts, n_memfds, n_fds, vec_size;
+	u64 n_parts, n_memfds, n_fds;
 
 	/*
 	 * Step 1:
@@ -334,7 +334,6 @@ static int kdbus_msg_examine(struct kdbus_msg *msg, struct kdbus_bus *bus,
 	n_parts = 0;
 	n_memfds = 0;
 	n_fds = 0;
-	vec_size = 0;
 
 	KDBUS_ITEMS_FOREACH(item, msg->items, KDBUS_ITEMS_SIZE(msg, items)) {
 		switch (item->type) {
@@ -342,9 +341,7 @@ static int kdbus_msg_examine(struct kdbus_msg *msg, struct kdbus_bus *bus,
 			void __force __user *ptr = KDBUS_PTR(item->vec.address);
 			u64 size = item->vec.size;
 
-			if (vec_size + size < vec_size)
-				return -EMSGSIZE;
-			if (vec_size + size > KDBUS_MSG_MAX_PAYLOAD_VEC_SIZE)
+			if (size > KDBUS_MSG_MAX_PAYLOAD_VEC_SIZE)
 				return -EMSGSIZE;
 			if (ptr && unlikely(!access_ok(VERIFY_READ, ptr, size)))
 				return -EFAULT;