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Temporary fix for stack smashing in mailinfo
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Signed-off-by: Alex Riesen <raa.lkml@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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@raalkml @gitster
raalkml authored and gitster committed Aug 31, 2007
1 parent 7d3c82a commit 8dabdfc
Showing 1 changed file with 50 additions and 35 deletions.
85 changes: 50 additions & 35 deletions builtin-mailinfo.c
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Expand Up @@ -287,12 +287,12 @@ static void cleanup_space(char *buf)
}
}

static void decode_header(char *it);
static void decode_header(char *it, unsigned itsize);
static char *header[MAX_HDR_PARSED] = {
"From","Subject","Date",
};

static int check_header(char *line, char **hdr_data, int overwrite)
static int check_header(char *line, unsigned linesize, char **hdr_data, int overwrite)
{
int i;

Expand All @@ -305,7 +305,7 @@ static int check_header(char *line, char **hdr_data, int overwrite)
/* Unwrap inline B and Q encoding, and optionally
* normalize the meta information to utf8.
*/
decode_header(line + len + 2);
decode_header(line + len + 2, linesize - len - 2);
hdr_data[i] = xmalloc(1000 * sizeof(char));
if (! handle_header(line, hdr_data[i], len + 2)) {
return 1;
Expand All @@ -316,14 +316,14 @@ static int check_header(char *line, char **hdr_data, int overwrite)
/* Content stuff */
if (!strncasecmp(line, "Content-Type", 12) &&
line[12] == ':' && isspace(line[12 + 1])) {
decode_header(line + 12 + 2);
decode_header(line + 12 + 2, linesize - 12 - 2);
if (! handle_content_type(line)) {
return 1;
}
}
if (!strncasecmp(line, "Content-Transfer-Encoding", 25) &&
line[25] == ':' && isspace(line[25 + 1])) {
decode_header(line + 25 + 2);
decode_header(line + 25 + 2, linesize - 25 - 2);
if (! handle_content_transfer_encoding(line)) {
return 1;
}
Expand Down Expand Up @@ -432,10 +432,15 @@ static int read_one_header_line(char *line, int sz, FILE *in)
return 1;
}

static int decode_q_segment(char *in, char *ot, char *ep, int rfc2047)
static int decode_q_segment(char *in, char *ot, unsigned otsize, char *ep, int rfc2047)
{
char *otend = ot + otsize;
int c;
while ((c = *in++) != 0 && (in <= ep)) {
if (ot == otend) {
*--ot = '\0';
return -1;
}
if (c == '=') {
int d = *in++;
if (d == '\n' || !d)
Expand All @@ -451,12 +456,17 @@ static int decode_q_segment(char *in, char *ot, char *ep, int rfc2047)
return 0;
}

static int decode_b_segment(char *in, char *ot, char *ep)
static int decode_b_segment(char *in, char *ot, unsigned otsize, char *ep)
{
/* Decode in..ep, possibly in-place to ot */
int c, pos = 0, acc = 0;
char *otend = ot + otsize;

while ((c = *in++) != 0 && (in <= ep)) {
if (ot == otend) {
*--ot = '\0';
return -1;
}
if (c == '+')
c = 62;
else if (c == '/')
Expand Down Expand Up @@ -518,7 +528,7 @@ static const char *guess_charset(const char *line, const char *target_charset)
return "latin1";
}

static void convert_to_utf8(char *line, const char *charset)
static void convert_to_utf8(char *line, unsigned linesize, const char *charset)
{
char *out;

Expand All @@ -534,11 +544,11 @@ static void convert_to_utf8(char *line, const char *charset)
if (!out)
die("cannot convert from %s to %s\n",
charset, metainfo_charset);
strcpy(line, out);
strlcpy(line, out, linesize);
free(out);
}

static int decode_header_bq(char *it)
static int decode_header_bq(char *it, unsigned itsize)
{
char *in, *out, *ep, *cp, *sp;
char outbuf[1000];
Expand Down Expand Up @@ -578,56 +588,60 @@ static int decode_header_bq(char *it)
default:
return rfc2047; /* no munging */
case 'b':
sz = decode_b_segment(cp + 3, piecebuf, ep);
sz = decode_b_segment(cp + 3, piecebuf, sizeof(piecebuf), ep);
break;
case 'q':
sz = decode_q_segment(cp + 3, piecebuf, ep, 1);
sz = decode_q_segment(cp + 3, piecebuf, sizeof(piecebuf), ep, 1);
break;
}
if (sz < 0)
return rfc2047;
if (metainfo_charset)
convert_to_utf8(piecebuf, charset_q);
convert_to_utf8(piecebuf, sizeof(piecebuf), charset_q);

sz = strlen(piecebuf);
if (outbuf + sizeof(outbuf) <= out + sz)
return rfc2047; /* no munging */
strcpy(out, piecebuf);
out += strlen(out);
out += sz;
in = ep + 2;
}
strcpy(out, in);
strcpy(it, outbuf);
strlcpy(it, outbuf, itsize);
return rfc2047;
}

static void decode_header(char *it)
static void decode_header(char *it, unsigned itsize)
{

if (decode_header_bq(it))
if (decode_header_bq(it, itsize))
return;
/* otherwise "it" is a straight copy of the input.
* This can be binary guck but there is no charset specified.
*/
if (metainfo_charset)
convert_to_utf8(it, "");
convert_to_utf8(it, itsize, "");
}

static void decode_transfer_encoding(char *line)
static void decode_transfer_encoding(char *line, unsigned linesize)
{
char *ep;

switch (transfer_encoding) {
case TE_QP:
ep = line + strlen(line);
decode_q_segment(line, line, ep, 0);
decode_q_segment(line, line, linesize, ep, 0);
break;
case TE_BASE64:
ep = line + strlen(line);
decode_b_segment(line, line, ep);
decode_b_segment(line, line, linesize, ep);
break;
case TE_DONTCARE:
break;
}
}

static int handle_filter(char *line);
static int handle_filter(char *line, unsigned linesize);

static int find_boundary(void)
{
Expand Down Expand Up @@ -655,7 +669,7 @@ static int handle_boundary(void)
"can't recover\n");
exit(1);
}
handle_filter(newline);
handle_filter(newline, sizeof(newline));

/* skip to the next boundary */
if (!find_boundary())
Expand All @@ -670,7 +684,7 @@ static int handle_boundary(void)

/* slurp in this section's info */
while (read_one_header_line(line, sizeof(line), fin))
check_header(line, p_hdr_data, 0);
check_header(line, sizeof(line), p_hdr_data, 0);

/* eat the blank line after section info */
return (fgets(line, sizeof(line), fin) != NULL);
Expand Down Expand Up @@ -709,9 +723,10 @@ static inline int patchbreak(const char *line)
}


static int handle_commit_msg(char *line)
static int handle_commit_msg(char *line, unsigned linesize)
{
static int still_looking = 1;
char *endline = line + linesize;

if (!cmitmsg)
return 0;
Expand All @@ -726,13 +741,13 @@ static int handle_commit_msg(char *line)
if (!*cp)
return 0;
}
if ((still_looking = check_header(cp, s_hdr_data, 0)) != 0)
if ((still_looking = check_header(cp, endline - cp, s_hdr_data, 0)) != 0)
return 0;
}

/* normalize the log message to UTF-8. */
if (metainfo_charset)
convert_to_utf8(line, charset);
convert_to_utf8(line, endline - line, charset);

if (patchbreak(line)) {
fclose(cmitmsg);
Expand All @@ -751,7 +766,7 @@ static int handle_patch(char *line)
return 0;
}

static int handle_filter(char *line)
static int handle_filter(char *line, unsigned linesize)
{
static int filter = 0;

Expand All @@ -760,7 +775,7 @@ static int handle_filter(char *line)
*/
switch (filter) {
case 0:
if (!handle_commit_msg(line))
if (!handle_commit_msg(line, linesize))
break;
filter++;
case 1:
Expand Down Expand Up @@ -792,14 +807,14 @@ static void handle_body(void)
/* flush any leftover */
if ((transfer_encoding == TE_BASE64) &&
(np != newline)) {
handle_filter(newline);
handle_filter(newline, sizeof(newline));
}
if (!handle_boundary())
return;
}

/* Unwrap transfer encoding */
decode_transfer_encoding(line);
decode_transfer_encoding(line, sizeof(line));

switch (transfer_encoding) {
case TE_BASE64:
Expand All @@ -808,7 +823,7 @@ static void handle_body(void)

/* binary data most likely doesn't have newlines */
if (message_type != TYPE_TEXT) {
rc = handle_filter(line);
rc = handle_filter(line, sizeof(newline));
break;
}

Expand All @@ -825,7 +840,7 @@ static void handle_body(void)
/* should be sitting on a new line */
*(++np) = 0;
op++;
rc = handle_filter(newline);
rc = handle_filter(newline, sizeof(newline));
np = newline;
}
} while (*op != 0);
Expand All @@ -835,7 +850,7 @@ static void handle_body(void)
break;
}
default:
rc = handle_filter(line);
rc = handle_filter(line, sizeof(newline));
}
if (rc)
/* nothing left to filter */
Expand Down Expand Up @@ -922,7 +937,7 @@ static int mailinfo(FILE *in, FILE *out, int ks, const char *encoding,

/* process the email header */
while (read_one_header_line(line, sizeof(line), fin))
check_header(line, p_hdr_data, 1);
check_header(line, sizeof(line), p_hdr_data, 1);

handle_body();
handle_info();
Expand Down

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