[NET]: Fix incorrect sg_mark_end() calls.
This fixes scatterlist corruptions added by
commit 68e3f5dd4db62619fdbe520d36c9ebf62e672256
[CRYPTO] users: Fix up scatterlist conversion errors
The issue is that the code calls sg_mark_end() which clobbers the
sg_page() pointer of the final scatterlist entry.
The first part fo the fix makes skb_to_sgvec() do __sg_mark_end().
After considering all skb_to_sgvec() call sites the most correct
solution is to call __sg_mark_end() in skb_to_sgvec() since that is
what all of the callers would end up doing anyways.
I suspect this might have fixed some problems in virtio_net which is
the sole non-crypto user of skb_to_sgvec().
Other similar sg_mark_end() cases were converted over to
__sg_mark_end() as well.
Arguably sg_mark_end() is a poorly named function because it doesn't
just "mark", it clears out the page pointer as a side effect, which is
what led to these bugs in the first place.
The one remaining plain sg_mark_end() call is in scsi_alloc_sgtable()
and arguably it could be converted to __sg_mark_end() if only so that
we can delete this confusing interface from linux/scatterlist.h
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/rxrpc/rxkad.c b/net/rxrpc/rxkad.c
index eebefb6e..c387cf6 100644
--- a/net/rxrpc/rxkad.c
+++ b/net/rxrpc/rxkad.c
@@ -237,7 +237,8 @@
len = data_size + call->conn->size_align - 1;
len &= ~(call->conn->size_align - 1);
- sg_init_table(sg, skb_to_sgvec(skb, sg, 0, len));
+ sg_init_table(sg, nsg);
+ skb_to_sgvec(skb, sg, 0, len);
crypto_blkcipher_encrypt_iv(&desc, sg, sg, len);
_leave(" = 0");
@@ -344,7 +345,7 @@
goto nomem;
sg_init_table(sg, nsg);
- sg_mark_end(sg, skb_to_sgvec(skb, sg, 0, 8));
+ skb_to_sgvec(skb, sg, 0, 8);
/* start the decryption afresh */
memset(&iv, 0, sizeof(iv));
@@ -426,7 +427,7 @@
}
sg_init_table(sg, nsg);
- sg_mark_end(sg, skb_to_sgvec(skb, sg, 0, skb->len));
+ skb_to_sgvec(skb, sg, 0, skb->len);
/* decrypt from the session key */
payload = call->conn->key->payload.data;
@@ -701,7 +702,7 @@
nsg++;
}
- sg_mark_end(sg, nsg);
+ __sg_mark_end(&sg[nsg - 1]);
ASSERTCMP(sg[0].length + sg[1].length, ==, buflen);
}