1From bd5773947af5ca80ca546ad5625818fc912bdd60 Mon Sep 17 00:00:00 2001
2From: "Roy.Li" <rongqing.li@windriver.com>
3Date: Thu, 22 Aug 2013 08:56:09 +0800
4Subject: [PATCH] tftp-hpa: add error check for disk filled up
5
6Upstream-status: Pending [Sent to http://www.syslinux.org/archives/2013-August/020765.html]
7
8Add error check when the write-buffer is finally flushed to the file,
9the caller can detect if the disk filled up (or had an i/o error) and
10return a NOSAPCE nak to the other side.
11
12Signed-off-by: Ming Liu <ming.liu@windriver.com>
13Signed-off-by: Roy.Li <rongqing.li@windriver.com>
14---
15 common/tftpsubs.c |    8 +++++---
16 tftpd/tftpd.c     |   12 ++++++++++--
17 2 files changed, 15 insertions(+), 5 deletions(-)
18
19diff --git a/common/tftpsubs.c b/common/tftpsubs.c
20index 8c999f6..b4d4ffe 100644
21--- a/common/tftpsubs.c
22+++ b/common/tftpsubs.c
23@@ -206,20 +206,22 @@ int write_behind(FILE * file, int convert)
24
25     p = buf;
26     ct = count;
27+    count = 0;
28     while (ct--) {              /* loop over the buffer */
29         c = *p++;               /* pick up a character */
30         if (prevchar == '\r') { /* if prev char was cr */
31             if (c == '\n')      /* if have cr,lf then just */
32-                fseek(file, -1, 1);     /* smash lf on top of the cr */
33+                count = count - 1;
34             else if (c == '\0') /* if have cr,nul then */
35                 goto skipit;    /* just skip over the putc */
36             /* else just fall through and allow it */
37         }
38-        putc(c, file);
39+        buf[count] = c;
40+        count ++;
41       skipit:
42         prevchar = c;
43     }
44-    return count;
45+    return write(fileno(file), buf, count);
46 }
47
48 /* When an error has occurred, it is possible that the two sides
49diff --git a/tftpd/tftpd.c b/tftpd/tftpd.c
50index 1873e70..c2adbda 100644
51--- a/tftpd/tftpd.c
52+++ b/tftpd/tftpd.c
53@@ -1681,7 +1681,11 @@ static void tftp_recvfile(const struct formats *pf, struct tftphdr *oap, int oac
54             syslog(LOG_WARNING, "tftpd: write(ack): %m");
55             goto abort;
56         }
57-        write_behind(file, pf->f_convert);
58+        if(write_behind(file, pf->f_convert) < 0) {
59+            nak(ENOSPACE, NULL);
60+            (void)fclose(file);
61+            goto abort;
62+        }
63         for (;;) {
64             n = recv_time(peer, dp, PKTSIZE, 0, &r_timeout);
65             if (n < 0) {        /* really? */
66@@ -1712,7 +1716,11 @@ static void tftp_recvfile(const struct formats *pf, struct tftphdr *oap, int oac
67             goto abort;
68         }
69     } while (size == segsize);
70-    write_behind(file, pf->f_convert);
71+    if(write_behind(file, pf->f_convert) < 0) {
72+        nak(ENOSPACE, NULL);
73+        (void)fclose(file);
74+        goto abort;
75+    }
76     (void)fclose(file);         /* close data file */
77
78     ap->th_opcode = htons((u_short) ACK);       /* send the "final" ack */
79--
801.7.10.4
81
82