* Tom Rini (trini@xxxxxxxxxxxxxxxxxxx) wrote:
> On Tue, Jan 20, 2009 at 05:47:14PM +0100, Eric Sesterhenn wrote:
> > * Jörn Engel (joern@xxxxxxxxx) wrote:
> > > On Fri, 16 January 2009 16:07:00 -0700, Tom Rini wrote:
> > > >
> > > > Sounds like a plan to me, except maybe zlib_inflate_unsafe() and a
> > > > comment above the wrapper saying what/why is going on?
> > >
> > > Eric, will you do the honors? Since you did all the hard work before,
> > > you derserve the fame as well. :)
> >
> > Since I am not sure either about xtensa I added chris to the cc list.
>
> How about we just change all callers from arch/*/boot to use the _unsafe
> version? Then..
>
> > +/*
> > + These two wrappers decide wheter strm->next_out gets checked for NULL.
> > + The zlib_inflate_unsafe() version got added because the PPC zImage
> > + gets extracted to memory address 0 and therefore
> > + we avoid this check for zlib_inflate_unsafe()
>
> These two wrappers decide wheter strm->next_out gets checked for NULL.
> The zlib_inflate_unsafe() version is primarily used in the pre-Linux
> 'boot' directory code to allow for extraction to memory address 0 and
> therefore we avoid this check.
This integrates Feedback from Tom to change xtensa and a comment, and
the callee/caller replace noticed by joern.
Some callers of zlib_inflate() might accidentally pass a NULL
pointer in strm->next_out which zlib_inflate() should catch.
Others like the powerpc gunzip_partial expect to be able
to extract a zImage to memory location 0. This introduces
zlib_inflate_usafe() for those and adds a check for the rest
Signed-off-by: Eric Sesterhenn <snakebyte@xxxxxx>
--- linux/arch/powerpc/boot/gunzip_util.c.orig 2009-01-21 09:27:39.000000000 +0100
+++ linux/arch/powerpc/boot/gunzip_util.c 2009-01-21 09:27:51.000000000 +0100
@@ -109,7 +109,7 @@ int gunzip_partial(struct gunzip_state *
state->s.next_out = dst;
state->s.avail_out = dstlen;
- r = zlib_inflate(&state->s, Z_FULL_FLUSH);
+ r = zlib_inflate_unsafe(&state->s, Z_FULL_FLUSH);
if (r != Z_OK && r != Z_STREAM_END)
fatal("inflate returned %d msg: %s\n\r", r, state->s.msg);
len = state->s.next_out - (unsigned char *)dst;
--- linux/arch/xtensa/boot/lib/zmem.c.orig 2009-01-21 09:22:44.000000000 +0100
+++ linux/arch/xtensa/boot/lib/zmem.c 2009-01-21 09:22:26.000000000 +0100
@@ -68,7 +68,7 @@ void gunzip (void *dst, int dstlen, unsi
s.avail_in = *lenp - i;
s.next_out = dst;
s.avail_out = dstlen;
- r = zlib_inflate(&s, Z_FINISH);
+ r = zlib_inflate_unsafe(&s, Z_FINISH);
if (r != Z_OK && r != Z_STREAM_END) {
//puts("inflate returned "); puthex(r); puts("\n");
exit();
--- linux/include/linux/zlib.h.orig 2009-01-21 09:27:28.000000000 +0100
+++ linux/include/linux/zlib.h 2009-01-21 09:28:55.000000000 +0100
@@ -329,7 +329,23 @@ extern int zlib_inflateInit (z_streamp s
*/
-extern int zlib_inflate (z_streamp strm, int flush);
+extern int __zlib_inflate (z_streamp strm, int flush, int check_out);
+/*
+ These two wrappers decide wheter strm->next_out gets checked for NULL.
+ The zlib_inflate_unsafe() version is primarily used in the pre-Linux
+ 'boot' directory code to allow for extraction to memory address 0 and
+ therefore we avoid this check.
+*/
+static inline int zlib_inflate(z_streamp strm, int flush)
+{
+ return __zlib_inflate(strm, flush, 1);
+}
+
+static inline int zlib_inflate_unsafe(z_streamp strm, int flush)
+{
+ return __zlib_inflate(strm, flush, 0);
+}
+
/*
inflate decompresses as much data as possible, and stops when the input
buffer becomes empty or the output buffer becomes full. It may introduce
--- linux/lib/zlib_inflate/inflate.c.orig 2009-01-21 09:27:11.000000000 +0100
+++ linux/lib/zlib_inflate/inflate.c 2009-01-21 09:29:10.000000000 +0100
@@ -329,7 +329,7 @@ static int zlib_inflateSyncPacket(z_stre
will return Z_BUF_ERROR if it has not reached the end of the stream.
*/
-int zlib_inflate(z_streamp strm, int flush)
+int __zlib_inflate(z_streamp strm, int flush, int check_out)
{
struct inflate_state *state;
const unsigned char *next; /* next input */
@@ -347,8 +347,10 @@ int zlib_inflate(z_streamp strm, int flu
static const unsigned short order[19] = /* permutation of code lengths */
{16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
- /* Do not check for strm->next_out == NULL here as ppc zImage
- inflates to strm->next_out = 0 */
+ /* We only check strm->next_out if the caller requests it,
+ since ppc extracts the ppc zImage to 0 */
+ if (check_out && !strm->next_out)
+ return Z_STREAM_ERROR;
if (strm == NULL || strm->state == NULL ||
(strm->next_in == NULL && strm->avail_in != 0))
--- linux/lib/zlib_inflate/inflate_syms.c.orig 2009-01-21 09:27:16.000000000 +0100
+++ linux/lib/zlib_inflate/inflate_syms.c 2009-01-21 09:27:51.000000000 +0100
@@ -11,7 +11,7 @@
#include <linux/zlib.h>
EXPORT_SYMBOL(zlib_inflate_workspacesize);
-EXPORT_SYMBOL(zlib_inflate);
+EXPORT_SYMBOL(__zlib_inflate);
EXPORT_SYMBOL(zlib_inflateInit2);
EXPORT_SYMBOL(zlib_inflateEnd);
EXPORT_SYMBOL(zlib_inflateReset);
--
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