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Message-ID: <53C8E1D6.8020906@sysgo.com>
Date: Fri, 18 Jul 2014 10:59:02 +0200
From: David Engraf <david.engraf@sysgo.com>
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To: Andrew Morton <akpm@linux-foundation.org>,
        "Daniel M. Weeks" <dan@danweeks.net>,
        Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
        linux-kernel@vger.kernel.org
Subject: [PATCH] add error checks to initramfs
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On a system with low memory extracting the initramfs may fail. If this 
happens the user gets "Failed to execute /init" instead of an initramfs 
error.

Check return value of sys_write and call error() when the write was 
incomplete or failed.

Signed-off-by: David Engraf <david.engraf@sysgo.com>


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diff --git a/init/initramfs.c b/init/initramfs.c
index a8497fa..64013cc 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -346,7 +346,8 @@ static int __init do_name(void)
 static int __init do_copy(void)
 {
 	if (count >= body_len) {
-		sys_write(wfd, victim, body_len);
+		if (sys_write(wfd, victim, body_len) != body_len)
+			error("write error");
 		sys_close(wfd);
 		do_utime(vcollected, mtime);
 		kfree(vcollected);
@@ -354,7 +355,8 @@ static int __init do_copy(void)
 		state = SkipIt;
 		return 0;
 	} else {
-		sys_write(wfd, victim, count);
+		if (sys_write(wfd, victim, count) != count)
+			error("write error");
 		body_len -= count;
 		eat(count);
 		return 1;

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