Blame SOURCES/0033-curl-7.61.1-CVE-2021-22925.patch

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From 2fbbf282e42ae476459f7efe68a88dcb63dcc43b Mon Sep 17 00:00:00 2001
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From: Daniel Stenberg <daniel@haxx.se>
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Date: Sat, 12 Jun 2021 18:25:15 +0200
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Subject: [PATCH] telnet: fix option parser to not send uninitialized contents
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CVE-2021-22925
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Reported-by: Red Hat Product Security
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Bug: https://curl.se/docs/CVE-2021-22925.html
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Upstream-commit: 894f6ec730597eb243618d33cc84d71add8d6a8a
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Signed-off-by: Kamil Dudka <kdudka@redhat.com>
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---
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 lib/telnet.c | 17 +++++++++++------
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 1 file changed, 11 insertions(+), 6 deletions(-)
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diff --git a/lib/telnet.c b/lib/telnet.c
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index ea6bc71..f8428b8 100644
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--- a/lib/telnet.c
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+++ b/lib/telnet.c
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@@ -967,12 +967,17 @@ static void suboption(struct connectdata *conn)
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         size_t tmplen = (strlen(v->data) + 1);
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         /* Add the variable only if it fits */
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         if(len + tmplen < (int)sizeof(temp)-6) {
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-          if(sscanf(v->data, "%127[^,],%127s", varname, varval) == 2) {
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-            snprintf((char *)&temp[len], sizeof(temp) - len,
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-                     "%c%s%c%s", CURL_NEW_ENV_VAR, varname,
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-                     CURL_NEW_ENV_VALUE, varval);
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-            len += tmplen;
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-          }
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+          int rv;
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+          char sep[2] = "";
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+          varval[0] = 0;
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+          rv = sscanf(v->data, "%127[^,]%1[,]%127s", varname, sep, varval);
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+          if(rv == 1)
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+            len += snprintf((char *)&temp[len], sizeof(temp) - len,
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+                            "%c%s", CURL_NEW_ENV_VAR, varname);
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+          else if(rv >= 2)
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+            len += snprintf((char *)&temp[len], sizeof(temp) - len,
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+                            "%c%s%c%s", CURL_NEW_ENV_VAR, varname,
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+                            CURL_NEW_ENV_VALUE, varval);
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         }
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       }
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       snprintf((char *)&temp[len], sizeof(temp) - len,
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-- 
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2.31.1
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