[NET]: Fix heavy stack usage in seq_file output routines.
Plan C: we can follow the Al Viro's proposal about %n like in this patch.
The same applies to udp, fib (the /proc/net/route file), rt_cache and
sctp debug. This is minus ~150-200 bytes for each.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index b053ac7..1f535e31 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1619,7 +1619,8 @@
}
/* ------------------------------------------------------------------------ */
-static void udp4_format_sock(struct sock *sp, char *tmpbuf, int bucket)
+static void udp4_format_sock(struct sock *sp, struct seq_file *f,
+ int bucket, int *len)
{
struct inet_sock *inet = inet_sk(sp);
__be32 dest = inet->daddr;
@@ -1627,13 +1628,13 @@
__u16 destp = ntohs(inet->dport);
__u16 srcp = ntohs(inet->sport);
- sprintf(tmpbuf, "%4d: %08X:%04X %08X:%04X"
- " %02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p",
+ seq_printf(f, "%4d: %08X:%04X %08X:%04X"
+ " %02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p%n",
bucket, src, srcp, dest, destp, sp->sk_state,
atomic_read(&sp->sk_wmem_alloc),
atomic_read(&sp->sk_rmem_alloc),
0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp),
- atomic_read(&sp->sk_refcnt), sp);
+ atomic_read(&sp->sk_refcnt), sp, len);
}
int udp4_seq_show(struct seq_file *seq, void *v)
@@ -1644,11 +1645,11 @@
"rx_queue tr tm->when retrnsmt uid timeout "
"inode");
else {
- char tmpbuf[129];
struct udp_iter_state *state = seq->private;
+ int len;
- udp4_format_sock(v, tmpbuf, state->bucket);
- seq_printf(seq, "%-127s\n", tmpbuf);
+ udp4_format_sock(v, seq, state->bucket, &len);
+ seq_printf(seq, "%*s\n", 127 - len ,"");
}
return 0;
}