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From: Matt Redfearn <matt.redfearn@imgtec.com>
To: Ralf Baechle <ralf@linux-mips.org>
Cc: <linux-mips@linux-mips.org>,
	Matt Redfearn <matt.redfearn@imgtec.com>,
	"# 4 . 7+" <stable@vger.kernel.org>,
	<linux-kernel@vger.kernel.org>
Subject: [PATCH] MIPS: KASLR: Fix handling of NULL FDT
Date: Mon, 17 Oct 2016 11:04:54 +0100	[thread overview]
Message-ID: <1476698694-6685-1-git-send-email-matt.redfearn@imgtec.com> (raw)

If platform code returns a NULL pointer to the FDT, initial_boot_params
will not get set to a valid pointer and attempting to find the /chosen
node in it will cause a NULL pointer dereference and the kernel to crash
immediately on startup - with no output to the console.

Fix this by checking that initial_boot_params is valid before using it.

Fixes: 405bc8fd12f5 ("MIPS: Kernel: Implement KASLR using CONFIG_RELOCATABLE")
Cc: <stable@vger.kernel.org> # 4.7+
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
---

 arch/mips/kernel/relocate.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/mips/kernel/relocate.c b/arch/mips/kernel/relocate.c
index ca1cc30c0891..8810183840ca 100644
--- a/arch/mips/kernel/relocate.c
+++ b/arch/mips/kernel/relocate.c
@@ -200,6 +200,7 @@ static inline __init unsigned long get_random_boot(void)
 
 #if defined(CONFIG_USE_OF)
 	/* Get any additional entropy passed in device tree */
+	if (initial_boot_params)
 	{
 		int node, len;
 		u64 *prop;
-- 
2.7.4

             reply	other threads:[~2016-10-17 10:05 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-10-17 10:04 Matt Redfearn [this message]
2016-10-17 10:08 ` James Hogan
2016-10-17 13:47 ` Sergei Shtylyov

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