Home Home > GIT Browse > SLE15-SP1
summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJiri Slaby <jslaby@suse.cz>2019-05-10 14:13:58 +0200
committerJiri Slaby <jslaby@suse.cz>2019-05-16 08:27:59 +0200
commit4b88152211b03ef2c7be6593e6327874f2cc39d3 (patch)
tree1346d07554448f86eeea9e312ad20364cffad24a
parent7ed3dc1dff61e015f1642ee55a4792a7f254b8e8 (diff)
net: rose: fix a possible stack overflow
(networking-stable-19_03_28). suse-commit: f6baad3741a195becea93e0f3180e5bf4b87772c
-rw-r--r--net/rose/rose_subr.c21
1 files changed, 12 insertions, 9 deletions
diff --git a/net/rose/rose_subr.c b/net/rose/rose_subr.c
index 7ca57741b2fb..7849f286bb93 100644
--- a/net/rose/rose_subr.c
+++ b/net/rose/rose_subr.c
@@ -105,16 +105,17 @@ void rose_write_internal(struct sock *sk, int frametype)
struct sk_buff *skb;
unsigned char *dptr;
unsigned char lci1, lci2;
- char buffer[100];
- int len, faclen = 0;
+ int maxfaclen = 0;
+ int len, faclen;
+ int reserve;
- len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 1;
+ reserve = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + 1;
+ len = ROSE_MIN_LEN;
switch (frametype) {
case ROSE_CALL_REQUEST:
len += 1 + ROSE_ADDR_LEN + ROSE_ADDR_LEN;
- faclen = rose_create_facilities(buffer, rose);
- len += faclen;
+ maxfaclen = 256;
break;
case ROSE_CALL_ACCEPTED:
case ROSE_CLEAR_REQUEST:
@@ -123,15 +124,16 @@ void rose_write_internal(struct sock *sk, int frametype)
break;
}
- if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
+ skb = alloc_skb(reserve + len + maxfaclen, GFP_ATOMIC);
+ if (!skb)
return;
/*
* Space for AX.25 header and PID.
*/
- skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + 1);
+ skb_reserve(skb, reserve);
- dptr = skb_put(skb, skb_tailroom(skb));
+ dptr = skb_put(skb, len);
lci1 = (rose->lci >> 8) & 0x0F;
lci2 = (rose->lci >> 0) & 0xFF;
@@ -146,7 +148,8 @@ void rose_write_internal(struct sock *sk, int frametype)
dptr += ROSE_ADDR_LEN;
memcpy(dptr, &rose->source_addr, ROSE_ADDR_LEN);
dptr += ROSE_ADDR_LEN;
- memcpy(dptr, buffer, faclen);
+ faclen = rose_create_facilities(dptr, rose);
+ skb_put(skb, faclen);
dptr += faclen;
break;