Restore the ability to continue booting after legacy image overwrite

Before new uImage code was merged, bootm code allowed for the kernel image to
get overwritten during decompresion. new uImage introduced a check for image
overwrites and refused to boot the image that got overwritten. This patch
restores the old behavior. It also adds a warning when the image overwriten is
a multi-image file, because in such case accessing componentes other than the
first one will fail.

Signed-off-by: Marian Balakowicz <m8@semihalf.com>

12 files changed, 39 insertions, 23 deletions

diff --git a/common/cmd_bootm.c b/common/cmd_bootm.c
index 9e5ce4b..3a0c83d 100644
--- a/common/cmd_bootm.c
+++ b/common/cmd_bootm.c
@@ -286,9 +286,16 @@ int do_bootm (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 		debug ("image_start = 0x%lX, image_end = 0x%lx\n", image_start, image_end);
 		debug ("load_start = 0x%lx, load_end = 0x%lx\n", load_start, load_end);
 
-		puts ("ERROR: image overwritten - must RESET the board to recover.\n");
-		show_boot_progress (-113);
-		do_reset (cmdtp, flag, argc, argv);
+		if (images.legacy_hdr_valid) {
+			if (image_get_type (&images.legacy_hdr_os_copy) == IH_TYPE_MULTI)
+				puts ("WARNING: legacy format multi component "
+					"image overwritten\n");
+		} else {
+			puts ("ERROR: new format image overwritten - "
+				"must RESET the board to recover\n");
+			show_boot_progress (-113);
+			do_reset (cmdtp, flag, argc, argv);
+		}
 	}
 
 	show_boot_progress (8);
@@ -533,9 +540,17 @@ static void *boot_get_kernel (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]
 			show_boot_progress (-5);
 			return NULL;
 		}
+
+		/*
+		 * copy image header to allow for image overwrites during kernel
+		 * decompression.
+		 */
+		memmove (&images->legacy_hdr_os_copy, hdr, sizeof(image_header_t));
+
+		/* save pointer to image header */
 		images->legacy_hdr_os = hdr;
-		images->legacy_hdr_valid = 1;
 
+		images->legacy_hdr_valid = 1;
 		show_boot_progress (6);
 		break;
 #if defined(CONFIG_FIT)
@@ -890,7 +905,7 @@ static void do_bootm_netbsd (cmd_tbl_t *cmdtp, int flag,
 	 * address of the original image header.
 	 */
 	os_hdr = NULL;
-	if (image_check_type (hdr, IH_TYPE_MULTI)) {
+	if (image_check_type (&images->legacy_hdr_os_copy, IH_TYPE_MULTI)) {
 		image_multi_getimg (hdr, 1, &kernel_data, &kernel_len);
 		if (kernel_len)
 			os_hdr = hdr;
@@ -947,7 +962,7 @@ static void do_bootm_lynxkdi (cmd_tbl_t *cmdtp, int flag,
 			     int argc, char *argv[],
 			     bootm_headers_t *images)
 {
-	image_header_t *hdr = images->legacy_hdr_os;
+	image_header_t *hdr = &images->legacy_hdr_os_copy;
 
 #if defined(CONFIG_FIT)
 	if (!images->legacy_hdr_valid) {
@@ -964,7 +979,7 @@ static void do_bootm_rtems (cmd_tbl_t *cmdtp, int flag,
 			   int argc, char *argv[],
 			   bootm_headers_t *images)
 {
-	image_header_t *hdr = images->legacy_hdr_os;
+	image_header_t *hdr = &images->legacy_hdr_os_copy;
 	void (*entry_point)(bd_t *);
 
 #if defined(CONFIG_FIT)
@@ -994,10 +1009,10 @@ static void do_bootm_vxworks (cmd_tbl_t *cmdtp, int flag,
 			     bootm_headers_t *images)
 {
 	char str[80];
-	image_header_t *hdr = images->legacy_hdr_os;
+	image_header_t *hdr = &images->legacy_hdr_os_copy;
 
 #if defined(CONFIG_FIT)
-	if (hdr == NULL) {
+	if (!images->legacy_hdr_valid) {
 		fit_unsupported_reset ("VxWorks");
 		do_reset (cmdtp, flag, argc, argv);
 	}
@@ -1014,7 +1029,7 @@ static void do_bootm_qnxelf(cmd_tbl_t *cmdtp, int flag,
 {
 	char *local_args[2];
 	char str[16];
-	image_header_t *hdr = images->legacy_hdr_os;
+	image_header_t *hdr = &images->legacy_hdr_os_copy;
 
 #if defined(CONFIG_FIT)
 	if (!images->legacy_hdr_valid) {
@@ -1041,7 +1056,7 @@ static void do_bootm_artos (cmd_tbl_t *cmdtp, int flag,
 	int i, j, nxt, len, envno, envsz;
 	bd_t *kbd;
 	void (*entry)(bd_t *bd, char *cmdline, char **fwenv, ulong top);
-	image_header_t *hdr = images->legacy_hdr_os;
+	image_header_t *hdr = &images->legacy_hdr_os_copy;
 
 #if defined(CONFIG_FIT)
 	if (!images->legacy_hdr_valid) {
diff --git a/common/image.c b/common/image.c
index 9e63432..d218f2f 100644
--- a/common/image.c
+++ b/common/image.c
@@ -983,7 +983,7 @@ int boot_get_ramdisk (int argc, char *argv[], bootm_headers_t *images,
 #endif /* CONFIG_B2 || CONFIG_EVB4510 || CONFIG_ARMADILLO */
 
 	} else if (images->legacy_hdr_valid &&
-			image_check_type (images->legacy_hdr_os, IH_TYPE_MULTI)) {
+			image_check_type (&images->legacy_hdr_os_copy, IH_TYPE_MULTI)) {
 		/*
 		 * Now check if we have a legacy mult-component image,
 		 * get second entry data start address and len.
diff --git a/include/image.h b/include/image.h
index c1a6cbb..60fdb2b 100644
--- a/include/image.h
+++ b/include/image.h
@@ -197,7 +197,8 @@ typedef struct bootm_headers {
 	 * then boot_get_ramdisk() and get_fdt() will attempt to get
 	 * data from second and third component accordingly.
 	 */
-	image_header_t	*legacy_hdr_os;
+	image_header_t	*legacy_hdr_os;		/* image header pointer */
+	image_header_t	legacy_hdr_os_copy;	/* header copy */
 	ulong		legacy_hdr_valid;
 
 #if defined(CONFIG_FIT)
diff --git a/lib_arm/bootm.c b/lib_arm/bootm.c
index c5e8cb3..6b4a807 100644
--- a/lib_arm/bootm.c
+++ b/lib_arm/bootm.c
@@ -78,7 +78,7 @@ void do_bootm_linux (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[],
 
 	/* find kernel entry point */
 	if (images->legacy_hdr_valid) {
-		ep = image_get_ep (images->legacy_hdr_os);
+		ep = image_get_ep (&images->legacy_hdr_os_copy);
 #if defined(CONFIG_FIT)
 	} else if (images->fit_uname_os) {
 		ret = fit_image_get_entry (images->fit_hdr_os,
diff --git a/lib_avr32/bootm.c b/lib_avr32/bootm.c
index b1c651a..5ff8c79 100644
--- a/lib_avr32/bootm.c
+++ b/lib_avr32/bootm.c
@@ -185,7 +185,7 @@ void do_bootm_linux(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[],
 
 	/* find kernel entry point */
 	if (images->legacy_hdr_valid) {
-		ep = image_get_ep (images->legacy_hdr_os);
+		ep = image_get_ep (&images->legacy_hdr_os_copy);
 #if defined(CONFIG_FIT)
 	} else if (images->fit_uname_os) {
 		ret = fit_image_get_entry (images->fit_hdr_os,
diff --git a/lib_blackfin/bootm.c b/lib_blackfin/bootm.c
index bea11ed..ef4b112 100644
--- a/lib_blackfin/bootm.c
+++ b/lib_blackfin/bootm.c
@@ -49,7 +49,7 @@ void do_bootm_linux(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[],
 
 	/* find kernel entry point */
 	if (images->legacy_hdr_valid) {
-		ep = image_get_ep (images->legacy_hdr_os);
+		ep = image_get_ep (&images->legacy_hdr_os_copy);
 #if defined(CONFIG_FIT)
 	} else if (images->fit_uname_os) {
 		int ret = fit_image_get_entry (images->fit_hdr_os,
diff --git a/lib_m68k/bootm.c b/lib_m68k/bootm.c
index 6f49c31..61f1a36 100644
--- a/lib_m68k/bootm.c
+++ b/lib_m68k/bootm.c
@@ -96,7 +96,7 @@ void do_bootm_linux(cmd_tbl_t * cmdtp, int flag,
 
 	/* find kernel entry point */
 	if (images->legacy_hdr_valid) {
-		ep = image_get_ep (images->legacy_hdr_os);
+		ep = image_get_ep (&images->legacy_hdr_os_copy);
 #if defined(CONFIG_FIT)
 	} else if (images->fit_uname_os) {
 		ret = fit_image_get_entry (images->fit_hdr_os,
diff --git a/lib_microblaze/bootm.c b/lib_microblaze/bootm.c
index fab4a54..30a03ef 100644
--- a/lib_microblaze/bootm.c
+++ b/lib_microblaze/bootm.c
@@ -44,7 +44,7 @@ void do_bootm_linux (cmd_tbl_t * cmdtp, int flag, int argc, char *argv[],
 
 	/* find kernel entry point */
 	if (images->legacy_hdr_valid) {
-		ep = image_get_ep (images->legacy_hdr_os);
+		ep = image_get_ep (&images->legacy_hdr_os_copy);
 #if defined(CONFIG_FIT)
 	} else if (images->fit_uname_os) {
 		int ret = fit_image_get_entry (images->fit_hdr_os,
diff --git a/lib_mips/bootm.c b/lib_mips/bootm.c
index e4c139e..f813fc5 100644
--- a/lib_mips/bootm.c
+++ b/lib_mips/bootm.c
@@ -57,7 +57,7 @@ void do_bootm_linux (cmd_tbl_t * cmdtp, int flag, int argc, char *argv[],
 
 	/* find kernel entry point */
 	if (images->legacy_hdr_valid) {
-		ep = image_get_ep (images->legacy_hdr_os);
+		ep = image_get_ep (&images->legacy_hdr_os_copy);
 #if defined(CONFIG_FIT)
 	} else if (images->fit_uname_os) {
 		ret = fit_image_get_entry (images->fit_hdr_os,
diff --git a/lib_nios2/bootm.c b/lib_nios2/bootm.c
index 0c89e96..01f4e87 100644
--- a/lib_nios2/bootm.c
+++ b/lib_nios2/bootm.c
@@ -34,7 +34,7 @@ void do_bootm_linux(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[],
 
 	/* find kernel entry point */
 	if (images->legacy_hdr_valid) {
-		ep = image_get_ep (images->legacy_hdr_os);
+		ep = image_get_ep (&images->legacy_hdr_os_copy);
 #if defined(CONFIG_FIT)
 	} else if (images->fit_uname_os) {
 		int ret = fit_image_get_entry (images->fit_hdr_os,
diff --git a/lib_ppc/bootm.c b/lib_ppc/bootm.c
index b24a064..0328bad 100644
--- a/lib_ppc/bootm.c
+++ b/lib_ppc/bootm.c
@@ -146,7 +146,7 @@ do_bootm_linux(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[],
 
 	/* find kernel entry point */
 	if (images->legacy_hdr_valid) {
-		ep = image_get_ep (images->legacy_hdr_os);
+		ep = image_get_ep (&images->legacy_hdr_os_copy);
 #if defined(CONFIG_FIT)
 	} else if (images->fit_uname_os) {
 		ret = fit_image_get_entry (images->fit_hdr_os,
@@ -639,7 +639,7 @@ static int boot_get_fdt (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[],
 		printf ("   Booting using the fdt blob at 0x%x\n", fdt_blob);
 
 	} else if (images->legacy_hdr_valid &&
-			image_check_type (images->legacy_hdr_os, IH_TYPE_MULTI)) {
+			image_check_type (&images->legacy_hdr_os_copy, IH_TYPE_MULTI)) {
 
 		ulong fdt_data, fdt_len;
 
diff --git a/lib_sh/bootm.c b/lib_sh/bootm.c
index 3d5c3bb..dd32a3e 100644
--- a/lib_sh/bootm.c
+++ b/lib_sh/bootm.c
@@ -67,7 +67,7 @@ void do_bootm_linux (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[],
 
 	/* find kernel entry point */
 	if (images->legacy_hdr_valid) {
-		ep = image_get_ep (images->legacy_hdr_os);
+		ep = image_get_ep (&images->legacy_hdr_os_copy);
 #if defined(CONFIG_FIT)
 	} else if (images->fit_uname_os) {
 		int ret = fit_image_get_entry (images->fit_hdr_os,