The current code requires \r as the terminator directly
after the last digit, and RFC959 indicates CRLF as the
the terminator.

However, we have seen in the wild a client sending
packets with only \n

Signed-off-by: Scott Parlane <scott.parl...@alliedtelesis.co.nz>
---
 net/netfilter/nf_conntrack_ftp.c | 40 ++++++++++++++++++++++++----------------
 1 file changed, 24 insertions(+), 16 deletions(-)

diff --git a/net/netfilter/nf_conntrack_ftp.c b/net/netfilter/nf_conntrack_ftp.c
index b666959f17..e15bf351f6 100644
--- a/net/netfilter/nf_conntrack_ftp.c
+++ b/net/netfilter/nf_conntrack_ftp.c
@@ -56,21 +56,23 @@ unsigned int (*nf_nat_ftp_hook)(struct sk_buff *skb,
 EXPORT_SYMBOL_GPL(nf_nat_ftp_hook);
 
 static int try_rfc959(const char *, size_t, struct nf_conntrack_man *,
-                     char, unsigned int *);
+                     char, char, unsigned int *);
 static int try_rfc1123(const char *, size_t, struct nf_conntrack_man *,
-                      char, unsigned int *);
+                      char, char, unsigned int *);
 static int try_eprt(const char *, size_t, struct nf_conntrack_man *,
-                   char, unsigned int *);
+                   char, char, unsigned int *);
 static int try_epsv_response(const char *, size_t, struct nf_conntrack_man *,
-                            char, unsigned int *);
+                            char, char, unsigned int *);
 
 static struct ftp_search {
        const char *pattern;
        size_t plen;
        char skip;
        char term;
+       char alt_term;
        enum nf_ct_ftp_type ftptype;
-       int (*getnum)(const char *, size_t, struct nf_conntrack_man *, char, 
unsigned int *);
+       int (*getnum)(const char *, size_t, struct nf_conntrack_man *, char,
+                     char, unsigned int *);
 } search[IP_CT_DIR_MAX][2] = {
        [IP_CT_DIR_ORIGINAL] = {
                {
@@ -78,6 +80,7 @@ static struct ftp_search {
                        .plen           = sizeof("PORT") - 1,
                        .skip           = ' ',
                        .term           = '\r',
+                       .alt_term       = '\n',
                        .ftptype        = NF_CT_FTP_PORT,
                        .getnum         = try_rfc959,
                },
@@ -119,7 +122,7 @@ get_ipv6_addr(const char *src, size_t dlen, struct in6_addr 
*dst, u_int8_t term)
 }
 
 static int try_number(const char *data, size_t dlen, u_int32_t array[],
-                     int array_size, char sep, char term)
+                     int array_size, char sep, char term, char alt_term)
 {
        u_int32_t i, len;
 
@@ -136,7 +139,9 @@ static int try_number(const char *data, size_t dlen, 
u_int32_t array[],
                        /* Unexpected character; true if it's the
                           terminator (or we don't care about one)
                           and we're finished. */
-                       if ((*data == term || !term) && i == array_size - 1)
+                       if ((*data == term || (alt_term &&
+                                              *data == alt_term) || !term) &&
+                           i == array_size - 1)
                                return len;
 
                        pr_debug("Char %u (got %u nums) `%u' unexpected\n",
@@ -152,12 +157,12 @@ static int try_number(const char *data, size_t dlen, 
u_int32_t array[],
 /* Returns 0, or length of numbers: 192,168,1,1,5,6 */
 static int try_rfc959(const char *data, size_t dlen,
                      struct nf_conntrack_man *cmd, char term,
-                     unsigned int *offset)
+                     char alt_term, unsigned int *offset)
 {
        int length;
        u_int32_t array[6];
 
-       length = try_number(data, dlen, array, 6, ',', term);
+       length = try_number(data, dlen, array, 6, ',', term, alt_term);
        if (length == 0)
                return 0;
 
@@ -179,7 +184,7 @@ static int try_rfc959(const char *data, size_t dlen,
  */
 static int try_rfc1123(const char *data, size_t dlen,
                       struct nf_conntrack_man *cmd, char term,
-                      unsigned int *offset)
+                      char alt_term, unsigned int *offset)
 {
        int i;
        for (i = 0; i < dlen; i++)
@@ -191,7 +196,7 @@ static int try_rfc1123(const char *data, size_t dlen,
 
        *offset += i;
 
-       return try_rfc959(data + i, dlen - i, cmd, 0, offset);
+       return try_rfc959(data + i, dlen - i, cmd, 0, 0, offset);
 }
 
 /* Grab port: number up to delimiter */
@@ -222,7 +227,7 @@ static int get_port(const char *data, int start, size_t 
dlen, char delim,
 
 /* Returns 0, or length of numbers: |1|132.235.1.2|6275| or |2|3ffe::1|6275| */
 static int try_eprt(const char *data, size_t dlen, struct nf_conntrack_man 
*cmd,
-                   char term, unsigned int *offset)
+                   char term, char alt_term, unsigned int *offset)
 {
        char delim;
        int length;
@@ -251,7 +256,8 @@ static int try_eprt(const char *data, size_t dlen, struct 
nf_conntrack_man *cmd,
                u_int32_t array[4];
 
                /* Now we have IP address. */
-               length = try_number(data + 3, dlen - 3, array, 4, '.', delim);
+               length = try_number(data + 3, dlen - 3, array, 4, '.', delim,
+                                   0);
                if (length != 0)
                        cmd->u3.ip = htonl((array[0] << 24) | (array[1] << 16)
                                           | (array[2] << 8) | array[3]);
@@ -271,7 +277,7 @@ static int try_eprt(const char *data, size_t dlen, struct 
nf_conntrack_man *cmd,
 /* Returns 0, or length of numbers: |||6446| */
 static int try_epsv_response(const char *data, size_t dlen,
                             struct nf_conntrack_man *cmd, char term,
-                            unsigned int *offset)
+                            char alt_term, unsigned int *offset)
 {
        char delim;
 
@@ -289,12 +295,13 @@ static int try_epsv_response(const char *data, size_t 
dlen,
 static int find_pattern(const char *data, size_t dlen,
                        const char *pattern, size_t plen,
                        char skip, char term,
+                       char alt_term,
                        unsigned int *numoff,
                        unsigned int *numlen,
                        struct nf_conntrack_man *cmd,
                        int (*getnum)(const char *, size_t,
                                      struct nf_conntrack_man *, char,
-                                     unsigned int *))
+                                     char, unsigned int *))
 {
        size_t i = plen;
 
@@ -337,7 +344,7 @@ static int find_pattern(const char *data, size_t dlen,
        pr_debug("Skipped up to `%c'!\n", skip);
 
        *numoff = i;
-       *numlen = getnum(data + i, dlen - i, cmd, term, numoff);
+       *numlen = getnum(data + i, dlen - i, cmd, term, alt_term, numoff);
        if (!*numlen)
                return -1;
 
@@ -461,6 +468,7 @@ skip_nl_seq:
                                     search[dir][i].plen,
                                     search[dir][i].skip,
                                     search[dir][i].term,
+                                    search[dir][i].alt_term,
                                     &matchoff, &matchlen,
                                     &cmd,
                                     search[dir][i].getnum);
-- 
2.16.1

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