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authorDaniel Stenberg <daniel@haxx.se>2017-08-14 23:33:23 +0200
committerDaniel Stenberg <daniel@haxx.se>2017-08-14 23:33:41 +0200
commitff50fe0348466cae1a9f9f759b362c03f7060c34 (patch)
tree6a5a6efbe7bd7b00e49982e09a5da8f8341de28c
parentb53b4e44241415c0a7ad857c72ec323109d2a7c0 (diff)
strtoofft: reduce integer overflow risks globally
... make sure we bail out on overflows. Reported-by: Brian Carpenter Closes #1758
-rw-r--r--lib/cookie.c23
-rw-r--r--lib/file.c24
-rw-r--r--lib/ftp.c33
-rw-r--r--lib/ftplistparser.c36
-rw-r--r--lib/http.c56
-rw-r--r--lib/http_chunks.c6
-rw-r--r--lib/http_proxy.c4
-rw-r--r--lib/imap.c9
-rw-r--r--lib/ssh.c17
-rw-r--r--lib/strtoofft.c63
-rw-r--r--lib/strtoofft.h35
-rw-r--r--src/tool_getparam.c11
-rw-r--r--src/tool_paramhlp.c10
13 files changed, 196 insertions, 131 deletions
diff --git a/lib/cookie.c b/lib/cookie.c
index 6b678aeb8..eba2536ef 100644
--- a/lib/cookie.c
+++ b/lib/cookie.c
@@ -593,14 +593,20 @@ Curl_cookie_add(struct Curl_easy *data,
} while(semiptr);
if(co->maxage) {
- co->expires =
- curlx_strtoofft((*co->maxage=='\"')?
- &co->maxage[1]:&co->maxage[0], NULL, 10);
- if(CURL_OFF_T_MAX - now < co->expires)
- /* avoid overflow */
+ CURLofft offt;
+ offt = curlx_strtoofft((*co->maxage=='\"')?
+ &co->maxage[1]:&co->maxage[0], NULL, 10,
+ &co->expires);
+ if(offt == CURL_OFFT_FLOW)
+ /* overflow, used max value */
co->expires = CURL_OFF_T_MAX;
- else
- co->expires += now;
+ else if(!offt) {
+ if(CURL_OFF_T_MAX - now < co->expires)
+ /* would overflow */
+ co->expires = CURL_OFF_T_MAX;
+ else
+ co->expires += now;
+ }
}
else if(co->expirestr) {
/* Note that if the date couldn't get parsed for whatever reason,
@@ -753,7 +759,8 @@ Curl_cookie_add(struct Curl_easy *data,
co->secure = strcasecompare(ptr, "TRUE")?TRUE:FALSE;
break;
case 4:
- co->expires = curlx_strtoofft(ptr, NULL, 10);
+ if(curlx_strtoofft(ptr, NULL, 10, &co->expires))
+ badcookie = TRUE;
break;
case 5:
co->name = strdup(ptr);
diff --git a/lib/file.c b/lib/file.c
index 666cbe75b..a8f29f2ca 100644
--- a/lib/file.c
+++ b/lib/file.c
@@ -139,26 +139,28 @@ static CURLcode file_range(struct connectdata *conn)
struct Curl_easy *data = conn->data;
if(data->state.use_range && data->state.range) {
- from=curlx_strtoofft(data->state.range, &ptr, 0);
+ CURLofft from_t;
+ CURLofft to_t;
+ from_t = curlx_strtoofft(data->state.range, &ptr, 0, &from);
+ if(from_t == CURL_OFFT_FLOW)
+ return CURLE_RANGE_ERROR;
while(*ptr && (ISSPACE(*ptr) || (*ptr=='-')))
ptr++;
- to=curlx_strtoofft(ptr, &ptr2, 0);
- if(ptr == ptr2) {
- /* we didn't get any digit */
- to=-1;
- }
- if((-1 == to) && (from>=0)) {
+ to_t = curlx_strtoofft(ptr, &ptr2, 0, &to);
+ if(to_t == CURL_OFFT_FLOW)
+ return CURLE_RANGE_ERROR;
+ if((to_t == CURL_OFFT_INVAL) && !from_t) {
/* X - */
data->state.resume_from = from;
DEBUGF(infof(data, "RANGE %" CURL_FORMAT_CURL_OFF_T " to end of file\n",
from));
}
- else if(from < 0) {
+ else if((from_t == CURL_OFFT_INVAL) && !to_t) {
/* -Y */
- data->req.maxdownload = -from;
- data->state.resume_from = from;
+ data->req.maxdownload = to;
+ data->state.resume_from = -to;
DEBUGF(infof(data, "RANGE the last %" CURL_FORMAT_CURL_OFF_T " bytes\n",
- -from));
+ to));
}
else {
/* X-Y */
diff --git a/lib/ftp.c b/lib/ftp.c
index 6e86e5386..481b14a88 100644
--- a/lib/ftp.c
+++ b/lib/ftp.c
@@ -2260,11 +2260,13 @@ static CURLcode ftp_state_size_resp(struct connectdata *conn,
{
CURLcode result = CURLE_OK;
struct Curl_easy *data=conn->data;
- curl_off_t filesize;
+ curl_off_t filesize = -1;
char *buf = data->state.buffer;
/* get the size from the ascii string: */
- filesize = (ftpcode == 213)?curlx_strtoofft(buf+4, NULL, 0):-1;
+ if(ftpcode == 213)
+ /* ignores parsing errors, which will make the size remain unknown */
+ (void)curlx_strtoofft(buf+4, NULL, 0, &filesize);
if(instate == FTP_SIZE) {
#ifdef CURL_FTP_HTTPSTYLE_HEAD
@@ -2435,7 +2437,7 @@ static CURLcode ftp_state_get_resp(struct connectdata *conn,
/* if we have nothing but digits: */
if(bytes++) {
/* get the number! */
- size = curlx_strtoofft(bytes, NULL, 0);
+ (void)curlx_strtoofft(bytes, NULL, 0, &size);
}
}
}
@@ -3466,31 +3468,32 @@ static CURLcode ftp_range(struct connectdata *conn)
{
curl_off_t from, to;
char *ptr;
- char *ptr2;
struct Curl_easy *data = conn->data;
struct ftp_conn *ftpc = &conn->proto.ftpc;
if(data->state.use_range && data->state.range) {
- from=curlx_strtoofft(data->state.range, &ptr, 0);
+ CURLofft from_t;
+ CURLofft to_t;
+ from_t = curlx_strtoofft(data->state.range, &ptr, 0, &from);
+ if(from_t == CURL_OFFT_FLOW)
+ return CURLE_RANGE_ERROR;
while(*ptr && (ISSPACE(*ptr) || (*ptr=='-')))
ptr++;
- to=curlx_strtoofft(ptr, &ptr2, 0);
- if(ptr == ptr2) {
- /* we didn't get any digit */
- to=-1;
- }
- if((-1 == to) && (from>=0)) {
+ to_t = curlx_strtoofft(ptr, NULL, 0, &to);
+ if(to_t == CURL_OFFT_FLOW)
+ return CURLE_RANGE_ERROR;
+ if((to_t == CURL_OFFT_INVAL) && !from_t) {
/* X - */
data->state.resume_from = from;
DEBUGF(infof(conn->data, "FTP RANGE %" CURL_FORMAT_CURL_OFF_T
" to end of file\n", from));
}
- else if(from < 0) {
+ else if(!to_t && (from_t == CURL_OFFT_INVAL)) {
/* -Y */
- data->req.maxdownload = -from;
- data->state.resume_from = from;
+ data->req.maxdownload = to;
+ data->state.resume_from = -to;
DEBUGF(infof(conn->data, "FTP RANGE the last %" CURL_FORMAT_CURL_OFF_T
- " bytes\n", -from));
+ " bytes\n", to));
}
else {
/* X-Y */
diff --git a/lib/ftplistparser.c b/lib/ftplistparser.c
index 2acce31d8..47fe1733b 100644
--- a/lib/ftplistparser.c
+++ b/lib/ftplistparser.c
@@ -609,16 +609,18 @@ size_t Curl_ftp_parselist(char *buffer, size_t size, size_t nmemb,
char *p;
curl_off_t fsize;
finfo->b_data[parser->item_offset + parser->item_length - 1] = 0;
- fsize = curlx_strtoofft(finfo->b_data+parser->item_offset, &p, 10);
- if(p[0] == '\0' && fsize != CURL_OFF_T_MAX &&
- fsize != CURL_OFF_T_MIN) {
- parser->file_data->info.flags |= CURLFINFOFLAG_KNOWN_SIZE;
- parser->file_data->info.size = fsize;
+ if(!curlx_strtoofft(finfo->b_data+parser->item_offset,
+ &p, 10, &fsize)) {
+ if(p[0] == '\0' && fsize != CURL_OFF_T_MAX &&
+ fsize != CURL_OFF_T_MIN) {
+ parser->file_data->info.flags |= CURLFINFOFLAG_KNOWN_SIZE;
+ parser->file_data->info.size = fsize;
+ }
+ parser->item_length = 0;
+ parser->item_offset = 0;
+ parser->state.UNIX.main = PL_UNIX_TIME;
+ parser->state.UNIX.sub.time = PL_UNIX_TIME_PREPART1;
}
- parser->item_length = 0;
- parser->item_offset = 0;
- parser->state.UNIX.main = PL_UNIX_TIME;
- parser->state.UNIX.sub.time = PL_UNIX_TIME_PREPART1;
}
else if(!ISDIGIT(c)) {
PL_ERROR(conn, CURLE_FTP_BAD_FILE_LIST);
@@ -935,19 +937,9 @@ size_t Curl_ftp_parselist(char *buffer, size_t size, size_t nmemb,
}
else {
char *endptr;
- finfo->size = curlx_strtoofft(finfo->b_data +
- parser->item_offset,
- &endptr, 10);
- if(!*endptr) {
- if(finfo->size == CURL_OFF_T_MAX ||
- finfo->size == CURL_OFF_T_MIN) {
- if(errno == ERANGE) {
- PL_ERROR(conn, CURLE_FTP_BAD_FILE_LIST);
- return bufflen;
- }
- }
- }
- else {
+ if(curlx_strtoofft(finfo->b_data +
+ parser->item_offset,
+ &endptr, 10, &finfo->size)) {
PL_ERROR(conn, CURLE_FTP_BAD_FILE_LIST);
return bufflen;
}
diff --git a/lib/http.c b/lib/http.c
index d66b8482f..35c7c3d43 100644
--- a/lib/http.c
+++ b/lib/http.c
@@ -3486,28 +3486,32 @@ CURLcode Curl_http_readwrite_headers(struct Curl_easy *data,
/* Check for Content-Length: header lines to get size */
if(!k->ignorecl && !data->set.ignorecl &&
checkprefix("Content-Length:", k->p)) {
- curl_off_t contentlength = curlx_strtoofft(k->p+15, NULL, 10);
- if(data->set.max_filesize &&
- contentlength > data->set.max_filesize) {
- failf(data, "Maximum file size exceeded");
- return CURLE_FILESIZE_EXCEEDED;
- }
- if(contentlength >= 0) {
- k->size = contentlength;
- k->maxdownload = k->size;
- /* we set the progress download size already at this point
- just to make it easier for apps/callbacks to extract this
- info as soon as possible */
- Curl_pgrsSetDownloadSize(data, k->size);
- }
- else {
- /* Negative Content-Length is really odd, and we know it
- happens for example when older Apache servers send large
- files */
- streamclose(conn, "negative content-length");
- infof(data, "Negative content-length: %" CURL_FORMAT_CURL_OFF_T
- ", closing after transfer\n", contentlength);
+ curl_off_t contentlength;
+ if(!curlx_strtoofft(k->p+15, NULL, 10, &contentlength)) {
+ if(data->set.max_filesize &&
+ contentlength > data->set.max_filesize) {
+ failf(data, "Maximum file size exceeded");
+ return CURLE_FILESIZE_EXCEEDED;
+ }
+ if(contentlength >= 0) {
+ k->size = contentlength;
+ k->maxdownload = k->size;
+ /* we set the progress download size already at this point
+ just to make it easier for apps/callbacks to extract this
+ info as soon as possible */
+ Curl_pgrsSetDownloadSize(data, k->size);
+ }
+ else {
+ /* Negative Content-Length is really odd, and we know it
+ happens for example when older Apache servers send large
+ files */
+ streamclose(conn, "negative content-length");
+ infof(data, "Negative content-length: %" CURL_FORMAT_CURL_OFF_T
+ ", closing after transfer\n", contentlength);
+ }
}
+ else
+ infof(data, "Illegal Content-Length: header\n");
}
/* check for Content-Type: header lines to get the MIME-type */
else if(checkprefix("Content-Type:", k->p)) {
@@ -3682,11 +3686,11 @@ CURLcode Curl_http_readwrite_headers(struct Curl_easy *data,
/* if it truly stopped on a digit */
if(ISDIGIT(*ptr)) {
- k->offset = curlx_strtoofft(ptr, NULL, 10);
-
- if(data->state.resume_from == k->offset)
- /* we asked for a resume and we got it */
- k->content_range = TRUE;
+ if(!curlx_strtoofft(ptr, NULL, 10, &k->offset)) {
+ if(data->state.resume_from == k->offset)
+ /* we asked for a resume and we got it */
+ k->content_range = TRUE;
+ }
}
else
data->state.resume_from = 0; /* get everything */
diff --git a/lib/http_chunks.c b/lib/http_chunks.c
index 1bdf6974c..fce00c21e 100644
--- a/lib/http_chunks.c
+++ b/lib/http_chunks.c
@@ -5,7 +5,7 @@
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
- * Copyright (C) 1998 - 2016, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
@@ -158,9 +158,7 @@ CHUNKcode Curl_httpchunk_read(struct connectdata *conn,
return CHUNKE_ILLEGAL_HEX;
}
- ch->datasize=curlx_strtoofft(ch->hexbuffer, &endptr, 16);
- if((ch->datasize == CURL_OFF_T_MAX) && (errno == ERANGE))
- /* overflow is an error */
+ if(curlx_strtoofft(ch->hexbuffer, &endptr, 16, &ch->datasize))
return CHUNKE_ILLEGAL_HEX;
ch->state = CHUNK_LF; /* now wait for the CRLF */
}
diff --git a/lib/http_proxy.c b/lib/http_proxy.c
index 36567d36f..5c5f8fb2c 100644
--- a/lib/http_proxy.c
+++ b/lib/http_proxy.c
@@ -523,8 +523,8 @@ static CURLcode CONNECT(struct connectdata *conn,
k->httpcode);
}
else {
- s->cl = curlx_strtoofft(s->line_start +
- strlen("Content-Length:"), NULL, 10);
+ (void)curlx_strtoofft(s->line_start +
+ strlen("Content-Length:"), NULL, 10, &s->cl);
}
}
else if(Curl_compareheader(s->line_start, "Connection:", "close"))
diff --git a/lib/imap.c b/lib/imap.c
index 48af2902a..bc20110c2 100644
--- a/lib/imap.c
+++ b/lib/imap.c
@@ -1070,10 +1070,11 @@ static CURLcode imap_state_fetch_resp(struct connectdata *conn, int imapcode,
if(*ptr == '{') {
char *endptr;
- size = curlx_strtoofft(ptr + 1, &endptr, 10);
- if(endptr - ptr > 1 && endptr[0] == '}' &&
- endptr[1] == '\r' && endptr[2] == '\0')
- parsed = TRUE;
+ if(!curlx_strtoofft(ptr + 1, &endptr, 10, &size)) {
+ if(endptr - ptr > 1 && endptr[0] == '}' &&
+ endptr[1] == '\r' && endptr[2] == '\0')
+ parsed = TRUE;
+ }
}
if(parsed) {
diff --git a/lib/ssh.c b/lib/ssh.c
index 9443e24b9..cc5178fe7 100644
--- a/lib/ssh.c
+++ b/lib/ssh.c
@@ -2233,18 +2233,25 @@ static CURLcode ssh_statemach_act(struct connectdata *conn, bool *block)
curl_off_t from, to;
char *ptr;
char *ptr2;
+ CURLofft to_t;
+ CURLofft from_t;
- from=curlx_strtoofft(conn->data->state.range, &ptr, 0);
+ from_t = curlx_strtoofft(conn->data->state.range, &ptr, 0, &from);
+ if(from_t == CURL_OFFT_FLOW)
+ return CURLE_RANGE_ERROR;
while(*ptr && (ISSPACE(*ptr) || (*ptr=='-')))
ptr++;
- to=curlx_strtoofft(ptr, &ptr2, 0);
- if((ptr == ptr2) /* no "to" value given */
+ to_t = curlx_strtoofft(ptr, &ptr2, 0, &to);
+ if(to_t == CURL_OFFT_FLOW)
+ return CURLE_RANGE_ERROR;
+ if((to_t == CURL_OFFT_INVAL) /* no "to" value given */
|| (to >= size)) {
to = size - 1;
}
- if(from < 0) {
+ if(from_t) {
/* from is relative to end of file */
- from += size;
+ from = size - to;
+ to = size - 1;
}
if(from > size) {
failf(data, "Offset (%"
diff --git a/lib/strtoofft.c b/lib/strtoofft.c
index c2adc7280..f057bb1d6 100644
--- a/lib/strtoofft.c
+++ b/lib/strtoofft.c
@@ -5,7 +5,7 @@
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
- * Copyright (C) 1998 - 2016, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
@@ -20,6 +20,7 @@
*
***************************************************************************/
+#include <errno.h>
#include "curl_setup.h"
#include "strtoofft.h"
@@ -32,6 +33,30 @@
* https://www.opengroup.org/onlinepubs/009695399/functions/strtoimax.html
*/
+#if (CURL_SIZEOF_CURL_OFF_T > CURL_SIZEOF_LONG)
+# ifdef HAVE_STRTOLL
+# define strtooff strtoll
+# else
+# if defined(_MSC_VER) && (_MSC_VER >= 1300) && (_INTEGRAL_MAX_BITS >= 64)
+# if defined(_SAL_VERSION)
+ _Check_return_ _CRTIMP __int64 __cdecl _strtoi64(
+ _In_z_ const char *_String,
+ _Out_opt_ _Deref_post_z_ char **_EndPtr, _In_ int _Radix);
+# else
+ _CRTIMP __int64 __cdecl _strtoi64(const char *_String,
+ char **_EndPtr, int _Radix);
+# endif
+# define strtooff _strtoi64
+# else
+ curl_off_t curlx_strtoll(const char *nptr, char **endptr, int base);
+# define strtooff curlx_strtoll
+# define NEED_CURL_STRTOLL 1
+# endif
+# endif
+#else
+# define strtooff strtol
+#endif
+
#ifdef NEED_CURL_STRTOLL
/* Range tests can be used for alphanum decoding if characters are consecutive,
@@ -48,11 +73,10 @@ static const char valchars[] =
static int get_char(char c, int base);
/**
- * Emulated version of the strtoll function. This extracts a long long
+ * Custom version of the strtooff function. This extracts a curl_off_t
* value from the given input string and returns it.
*/
-curl_off_t
-curlx_strtoll(const char *nptr, char **endptr, int base)
+static curl_off_t strtooff(const char *nptr, char **endptr, int base)
{
char *end;
int is_negative = 0;
@@ -186,3 +210,34 @@ static int get_char(char c, int base)
return value;
}
#endif /* Only present if we need strtoll, but don't have it. */
+
+/*
+ * Parse a *positive* up to 64 bit number written in ascii.
+ */
+CURLofft curlx_strtoofft(const char *str, char **endp, int base,
+ curl_off_t *num)
+{
+ char *end;
+ curl_off_t number;
+ errno = 0;
+ *num = 0; /* clear by default */
+ while(str && *str && ISSPACE(*str))
+ str++;
+ if('-' == *str) {
+ if(endp)
+ *endp = (char *)str; /* didn't actually move */
+ return CURL_OFFT_INVAL; /* nothing parsed */
+ }
+ number = strtooff(str, &end, base);
+ if(endp)
+ *endp = end;
+ if(errno == ERANGE)
+ /* overflow/underflow */
+ return CURL_OFFT_FLOW;
+ else if(str == end)
+ /* nothing parsed */
+ return CURL_OFFT_INVAL;
+
+ *num = number;
+ return CURL_OFFT_OK;
+}
diff --git a/lib/strtoofft.h b/lib/strtoofft.h
index f4039f3a3..ac1fa4aa4 100644
--- a/lib/strtoofft.h
+++ b/lib/strtoofft.h
@@ -7,7 +7,7 @@
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
- * Copyright (C) 1998 - 2014, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
@@ -40,30 +40,6 @@
* of 'long' the conversion function to use is strtol().
*/
-#if (CURL_SIZEOF_CURL_OFF_T > CURL_SIZEOF_LONG)
-# ifdef HAVE_STRTOLL
-# define curlx_strtoofft strtoll
-# else
-# if defined(_MSC_VER) && (_MSC_VER >= 1300) && (_INTEGRAL_MAX_BITS >= 64)
-# if defined(_SAL_VERSION)
- _Check_return_ _CRTIMP __int64 __cdecl _strtoi64(
- _In_z_ const char *_String,
- _Out_opt_ _Deref_post_z_ char **_EndPtr, _In_ int _Radix);
-# else
- _CRTIMP __int64 __cdecl _strtoi64(const char *_String,
- char **_EndPtr, int _Radix);
-# endif
-# define curlx_strtoofft _strtoi64
-# else
- curl_off_t curlx_strtoll(const char *nptr, char **endptr, int base);
-# define curlx_strtoofft curlx_strtoll
-# define NEED_CURL_STRTOLL 1
-# endif
-# endif
-#else
-# define curlx_strtoofft strtol
-#endif
-
#if (CURL_SIZEOF_CURL_OFF_T == 4)
# define CURL_OFF_T_MAX CURL_OFF_T_C(0x7FFFFFFF)
#else
@@ -72,4 +48,13 @@
#endif
#define CURL_OFF_T_MIN (-CURL_OFF_T_MAX - CURL_OFF_T_C(1))
+typedef enum {
+ CURL_OFFT_OK, /* parsed fine */
+ CURL_OFFT_FLOW, /* over or underflow */
+ CURL_OFFT_INVAL /* nothing was parsed */
+} CURLofft;
+
+CURLofft curlx_strtoofft(const char *str, char **endp, int base,
+ curl_off_t *num);
+
#endif /* HEADER_CURL_STRTOOFFT_H */
diff --git a/src/tool_getparam.c b/src/tool_getparam.c
index b7ee519b3..40b39a8aa 100644
--- a/src/tool_getparam.c
+++ b/src/tool_getparam.c
@@ -590,7 +590,11 @@ ParameterError getparameter(const char *flag, /* f or -long-flag */
{
/* We support G, M, K too */
char *unit;
- curl_off_t value = curlx_strtoofft(nextarg, &unit, 0);
+ curl_off_t value;
+ if(curlx_strtoofft(nextarg, &unit, 0, &value)) {
+ warnf(global, "unsupported rate\n");
+ return PARAM_BAD_USE;
+ }
if(!*unit)
unit = (char *)"b";
@@ -1843,10 +1847,13 @@ ParameterError getparameter(const char *flag, /* f or -long-flag */
if(ISDIGIT(*nextarg) && !strchr(nextarg, '-')) {
char buffer[32];
curl_off_t off;
+ if(curlx_strtoofft(nextarg, NULL, 10, &off)) {
+ warnf(global, "unsupported range point\n");
+ return PARAM_BAD_USE;
+ }
warnf(global,
"A specified range MUST include at least one dash (-). "
"Appending one for you!\n");
- off = curlx_strtoofft(nextarg, NULL, 10);
snprintf(buffer, sizeof(buffer), "%" CURL_FORMAT_CURL_OFF_T "-", off);
Curl_safefree(config->range);
config->range = strdup(buffer);
diff --git a/src/tool_paramhlp.c b/src/tool_paramhlp.c
index 85c5e79a7..86a3fe6b0 100644
--- a/src/tool_paramhlp.c
+++ b/src/tool_paramhlp.c
@@ -400,9 +400,13 @@ ParameterError str2offset(curl_off_t *val, const char *str)
return PARAM_NEGATIVE_NUMERIC;
#if(CURL_SIZEOF_CURL_OFF_T > CURL_SIZEOF_LONG)
- *val = curlx_strtoofft(str, &endptr, 0);
- if((*val == CURL_OFF_T_MAX || *val == CURL_OFF_T_MIN) && (errno == ERANGE))
- return PARAM_NUMBER_TOO_LARGE;
+ {
+ CURLofft offt = curlx_strtoofft(str, &endptr, 0, val);
+ if(CURL_OFFT_FLOW == offt)
+ return PARAM_NUMBER_TOO_LARGE;
+ else if(CURL_OFFT_INVAL == offt)
+ return PARAM_BAD_NUMERIC;
+ }
#else
errno = 0;
*val = strtol(str, &endptr, 0);