BUG/MEDIUM: capture: capture-req/capture-res converters crash without a stream

Since commit 5f940703b3 ("MINOR: log: Don't depends on a stream to process
samples in log-format string") it has become quite obvious that a few sample
fetch functions and converters were still heavily dependent on the presence
of a stream without testing for it.

The capture-req and capture-res converters were in this case and could
crash the process if misused.

This fix adds a check for the stream's existence, and should be backported
to all stable versions up to 1.6.

(cherry picked from commit 5575896ba1120f136e680fd669afb5b084faa530)
Signed-off-by: Willy Tarreau <w@1wt.eu>

diff --git a/src/http_conv.c b/src/http_conv.c
index f496c56..fdf3c42 100644 (file)
--- a/src/http_conv.c
+++ b/src/http_conv.c
@@ -276,7 +276,7 @@ static int sample_conv_url_dec(const struct arg *args, struct sample *smp, void
 
 static int smp_conv_req_capture(const struct arg *args, struct sample *smp, void *private)
 {
-       struct proxy *fe = strm_fe(smp->strm);
+       struct proxy *fe;
        int idx, i;
        struct cap_hdr *hdr;
        int len;
@@ -284,6 +284,10 @@ static int smp_conv_req_capture(const struct arg *args, struct sample *smp, void
        if (!args || args->type != ARGT_SINT)
                return 0;
 
+       if (!smp->strm)
+               return 0;
+
+       fe = strm_fe(smp->strm);
        idx = args->data.sint;
 
        /* Check the availibity of the capture id. */
@@ -317,7 +321,7 @@ static int smp_conv_req_capture(const struct arg *args, struct sample *smp, void
 
 static int smp_conv_res_capture(const struct arg *args, struct sample *smp, void *private)
 {
-       struct proxy *fe = strm_fe(smp->strm);
+       struct proxy *fe;
        int idx, i;
        struct cap_hdr *hdr;
        int len;
@@ -325,6 +329,10 @@ static int smp_conv_res_capture(const struct arg *args, struct sample *smp, void
        if (!args || args->type != ARGT_SINT)
                return 0;
 
+       if (!smp->strm)
+               return 0;
+
+       fe = strm_fe(smp->strm);
        idx = args->data.sint;
 
        /* Check the availibity of the capture id. */