r4309 - branches/2.0/varnish-cache/bin/varnishd

[tfheen at projects.linpro.no]

Author: tfheen
Date: 2009-10-08 16:34:44 +0200 (Thu, 08 Oct 2009)
New Revision: 4309

Modified:
   branches/2.0/varnish-cache/bin/varnishd/shmlog.c
Log:
Merge r4200: Be more paranoid about shmlog magics,

Don't explode manager if it gets overwritten.



Modified: branches/2.0/varnish-cache/bin/varnishd/shmlog.c
===================================================================
--- branches/2.0/varnish-cache/bin/varnishd/shmlog.c	2009-10-08 14:29:34 UTC (rev 4308)
+++ branches/2.0/varnish-cache/bin/varnishd/shmlog.c	2009-10-08 14:34:44 UTC (rev 4309)
@@ -71,16 +71,19 @@
 vsl_wrap(void)
 {
 
+	assert(loghead->magic == SHMLOGHEAD_MAGIC);
 	*logstart = SLT_ENDMARKER;
 	logstart[loghead->ptr] = SLT_WRAPMARKER;
 	loghead->ptr = 0;
 	VSL_stats->shm_cycles++;
+	assert(loghead->magic == SHMLOGHEAD_MAGIC);
 }
 
 static void
 vsl_hdr(enum shmlogtag tag, unsigned char *p, unsigned len, unsigned id)
 {
 
+	assert(loghead->magic == SHMLOGHEAD_MAGIC);
 	assert(len < 0x10000);
 	assert(id < 0x10000);
 	p[__SHMLOG_LEN_HIGH] = (len >> 8) & 0xff;
@@ -280,13 +283,18 @@
 void
 VSL_Panic(int *len, char **ptr)
 {
+	static char a[1] = { '\0' }; 
 
 	AN(len);
 	AN(ptr);
-	assert(loghead->magic == SHMLOGHEAD_MAGIC);
-	assert(loghead->hdrsize == sizeof *loghead);
-	*len = sizeof(loghead->panicstr);
-	*ptr = loghead->panicstr;
+	if (loghead->magic == SHMLOGHEAD_MAGIC) {
+		assert(loghead->hdrsize == sizeof *loghead);
+		*len = sizeof(loghead->panicstr);
+		*ptr = loghead->panicstr;
+	} else {
+		*len = 0;
+		*ptr = a;
+	}
 }
 
 /*--------------------------------------------------------------------*/