Subject: [PATCH 2/5] netfilter: nf_conntrack_ftp: Fix debug output

From: Pablo Neira Ayuso <[email-masked]>
Date: Fri, 30 Aug 2019 14:07:01 +0200

From: Thomas Jarosch <[email-masked]>

The find_pattern() debug output was printing the 'skip' character.
This can be a NULL-byte and messes up further pr_debug() output.

Output without the fix:
kernel: nf_conntrack_ftp: Pattern matches!
kernel: nf_conntrack_ftp: Skipped up to `<7>nf_conntrack_ftp: find_pattern `PORT': dlen = 8
kernel: nf_conntrack_ftp: find_pattern `EPRT': dlen = 8

Output with the fix:
kernel: nf_conntrack_ftp: Pattern matches!
kernel: nf_conntrack_ftp: Skipped up to 0x0 delimiter!
kernel: nf_conntrack_ftp: Match succeeded!
kernel: nf_conntrack_ftp: conntrack_ftp: match `172,17,0,100,200,207' (20 bytes at 4150681645)
kernel: nf_conntrack_ftp: find_pattern `PORT': dlen = 8

Signed-off-by: Thomas Jarosch <[email-masked]>
Signed-off-by: Pablo Neira Ayuso <[email-masked]>
---
 net/netfilter/nf_conntrack_ftp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netfilter/nf_conntrack_ftp.c b/net/netfilter/nf_conntrack_ftp.c
index 0ecb3e289ef2..8d96738b7dfd 100644
--- a/net/netfilter/nf_conntrack_ftp.c
+++ b/net/netfilter/nf_conntrack_ftp.c
@@ -322,7 +322,7 @@ static int find_pattern(const char *data, size_t dlen,
 		i++;
 	}
 
-	pr_debug("Skipped up to `%c'!\n", skip);
+	pr_debug("Skipped up to 0x%hhx delimiter!\n", skip);
 
 	*numoff = i;
 	*numlen = getnum(data + i, dlen - i, cmd, term, numoff);
-- 
2.11.0