Skip to contentSkip to conversation

!CFG_MEMTEST_SCRATCH - do not dereference NULL ptr

PATCH Wolfgang Denk 2 participants 4 messages Nov 22, 2004 – Nov 29, 2004 1 message not in the archive

lore
Share & tools
lore

A message that is not in the archive (sent off-list or not yet received): 20041122100122.GA5418@simek

Wolfgang Denk

author
#1 lore raw
Quoted 6 lines · In message <20041122100122.GA5418@simek> you wrote:

this is resend of mail from Fri Nov 19 18:49:37. I can't find it in archive.

Index: common/cmd_mem.c
===================================================================

I hereby reject this patch.

There is no explanation what it does or which problem it is supposed to fix.

There is also no CHANGELOG entry.

Please read the README and resubmit with the required information.

Sorry.

Best regards,

Wolfgang Denk

Signature · 3 lines
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
The following statement is not true.  The previous statement is true.
#2 lore raw
Quoted 2 lines · Wolfgang Denk

There is no explanation what it does or which problem it is supposed to fix.

When CFG_MEMTEST_SCRATCH is undefined alternate memory test in do_mem_mtest (with CFG_ALT_MEMTEST defined) dereferences null pointer. It defines:
vu_long *dummy = NULL;
and later does:
*dummy = ~val;

Quoted 1 line

There is also no CHANGELOG entry.

CHANGELOG
* Patch by Ladislav Michl, 22 November 2004
- Fix NULL pointer dereference in alternate memory test (CFG_ALT_MEMTEST) when if no CFG_MEMTEST_SCRATCH area defined

Index: common/cmd_mem.c
===================================================================
RCS file: /cvsroot/u-boot/u-boot/common/cmd_mem.c,v retrieving revision 1.19

cmd_mem.c +5 -4
diff -p -u -r1.19 cmd_mem.c
@@ -646,8 +646,9 @@ int do_mem_mtest (cmd_tbl_t *cmdtp, int 
 	vu_long	num_words;
 #if defined(CFG_MEMTEST_SCRATCH)
 	vu_long *dummy = (vu_long*)CFG_MEMTEST_SCRATCH;
+#define write_dummy(val)	do { *dummy  = ~val; } while (0)
 #else
-	vu_long *dummy = NULL;
+#define write_dummy(val)	do { } while (0)
 #endif
 	int	j;
 	int iterations = 1;

@@ -723,7 +724,7 @@ int do_mem_mtest (cmd_tbl_t *cmdtp, int 
 		    val = bitpattern[j];
 		    for(; val != 0; val <<= 1) {
 			*addr  = val;
-			*dummy  = ~val; /* clear the test data off of the bus */
+			write_dummy(~val); /* clear the test data off of the bus */
 			readback = *addr;
 			if(readback != val) {
 			     printf ("FAILURE (data line): "

@@ -731,11 +732,11 @@ int do_mem_mtest (cmd_tbl_t *cmdtp, int 
 					  val, readback);
 			}
 			*addr  = ~val;
-			*dummy  = val;
+			write_dummy(val);
 			readback = *addr;
 			if(readback != ~val) {
 			    printf ("FAILURE (data line): "
-				"Is %08lx, should be %08lx\n",
+				"is %08lx, should be %08lx\n",
 					readback, ~val);
 			}
 		    }
#3 lore raw
Quoted 4 lines · Ladislav Michl

CHANGELOG
* Patch by Ladislav Michl, 22 November 2004
- Fix NULL pointer dereference in alternate memory test (CFG_ALT_MEMTEST) when if no CFG_MEMTEST_SCRATCH area defined

Wolfgang, any comments on this?

Regards,
ladis

author
#4 lore raw
Quoted 7 lines · In message <20041129092025.GB5558@simek> you wrote:
Quoted 4 lines · Ladislav Michl

CHANGELOG
* Patch by Ladislav Michl, 22 November 2004
- Fix NULL pointer dereference in alternate memory test (CFG_ALT_MEMTEST) when if no CFG_MEMTEST_SCRATCH area defined

Wolfgang, any comments on this?

Not yet; it's in my queue.

Best regards,

Wolfgang Denk

Signature · 5 lines
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Women professionals do tend to over-compensate.
	-- Dr. Elizabeth Dehaver, "Where No Man Has Gone Before",
	   stardate 1312.9.