kernel: Fix environment pointer setup in ar71xx/ath79

Observed on ar71xx/ath79 platforms such as Ubiquiti RouterStations.Reported in #20642.:
(https://dev.openwrt.org/ticket/20642).

If embedded command-line text exists with CONFIG_IMAGE_CMDLINE_HACK=y,firmware
init doesn't initialize environment pointer (fw_init_cmdline not called).

arcs_cmdline is not initialized before calling strlcat.

Signed-off-by: Ted Hess <thess@kitschensync.net>
Tested-by: Stijn Tintel <stijn@linux-ipv6.be>
SVN-Revision: 47270

diff --git a/target/linux/ar71xx/patches-4.1/508-MIPS-ath79-prom-image-command-line-hack.patch b/target/linux/ar71xx/patches-4.1/508-MIPS-ath79-prom-image-command-line-hack.patch
index ff9f1aa1415ec551d938b3bd127c27850b43e2e2..cfa5e72eec7d97fdac73f0bab7ef6ae495796528 100644 (file)
--- a/target/linux/ar71xx/patches-4.1/508-MIPS-ath79-prom-image-command-line-hack.patch
+++ b/target/linux/ar71xx/patches-4.1/508-MIPS-ath79-prom-image-command-line-hack.patch
@@ -1,6 +1,6 @@
 --- a/arch/mips/ath79/prom.c
 +++ b/arch/mips/ath79/prom.c
-@@ -33,6 +33,35 @@ static void __init ath79_prom_append_cmd
+@@ -33,6 +33,41 @@ static void __init ath79_prom_append_cmd
        strlcat(arcs_cmdline, ath79_cmdline_buf, sizeof(arcs_cmdline));
  }
  
@@ -27,6 +27,12 @@
 +              strlcat(arcs_cmdline, p, sizeof(arcs_cmdline));
 +      }
 +
++      /* Validate and setup environment pointer */
++      if (fw_arg2 < CKSEG0)
++              _fw_envp = NULL;
++      else
++              _fw_envp = (int *)fw_arg2;
++
 +      return 1;
 +}
 +#else
@@ -36,7 +42,7 @@
  static int __init ath79_prom_init_myloader(void)
  {
        struct myloader_info *mylo;
-@@ -61,6 +90,8 @@ static int __init ath79_prom_init_myload
+@@ -61,6 +96,8 @@ static int __init ath79_prom_init_myload
  
        ath79_prom_append_cmdline("ethaddr", mac_buf);
  
@@ -45,7 +51,7 @@
        return 1;
  }
  
-@@ -71,7 +102,8 @@ void __init prom_init(void)
+@@ -71,7 +108,8 @@ void __init prom_init(void)
        if (ath79_prom_init_myloader())
                return;
  
@@ -55,3 +61,13 @@
  
        env = fw_getenv("ethaddr");
        if (env)
+--- a/arch/mips/fw/lib/cmdline.c
++++ b/arch/mips/fw/lib/cmdline.c
+@@ -35,6 +35,7 @@ void __init fw_init_cmdline(void)
+       else
+               _fw_envp = (int *)fw_arg2;
+ 
++      arcs_cmdline[0] = '\0';
+       for (i = 1; i < fw_argc; i++) {
+               strlcat(arcs_cmdline, fw_argv(i), COMMAND_LINE_SIZE);
+               if (i < (fw_argc - 1))