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From e40ba375b6007ff227d18aa55be7f1070145ccac Mon Sep 17 00:00:00 2001
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From: Laszlo Ersek <lersek@redhat.com>
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Date: Fri, 7 Nov 2014 17:18:07 +0100
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Subject: [PATCH 20/41] dump: fill in the flat header signature more pleasingly
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 to the eye
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Message-id: <1415380693-16593-21-git-send-email-lersek@redhat.com>
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Patchwork-id: 62206
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O-Subject: [RHEL-7.1 qemu-kvm PATCH 20/26] dump: fill in the flat header signature more pleasingly to the eye
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Bugzilla: 1157798
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RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
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RH-Acked-by: Luiz Capitulino <lcapitulino@redhat.com>
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RH-Acked-by: dgibson <dgibson@redhat.com>
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The "mh.signature" array field has size 16, and is zeroed by the preceding
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memset(). MAKEDUMPFILE_SIGNATURE expands to a string literal with string
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length 12 (size 13). There's no need to measure the length of
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MAKEDUMPFILE_SIGNATURE at runtime, nor for the extra zero-filling of
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"mh.signature" with strncpy().
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Use memcpy() with MIN(sizeof, sizeof) for robustness (which is an integer
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constant expression, evaluable at compile time.)
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Approximately-suggested-by: Paolo Bonzini <pbonzini@redhat.com>
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Signed-off-by: Laszlo Ersek <lersek@redhat.com>
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Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
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Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
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(cherry picked from commit ae3f88f60fb9f42bb3679311c2fbff8e1868ea47)
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Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
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---
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 dump.c | 4 ++--
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 1 file changed, 2 insertions(+), 2 deletions(-)
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diff --git a/dump.c b/dump.c
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index 9250594..533b914 100644
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--- a/dump.c
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+++ b/dump.c
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@@ -722,8 +722,8 @@ static int write_start_flat_header(int fd)
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     int ret = 0;
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     memset(&mh, 0, sizeof(mh));
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-    strncpy(mh.signature, MAKEDUMPFILE_SIGNATURE,
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-            strlen(MAKEDUMPFILE_SIGNATURE));
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+    memcpy(mh.signature, MAKEDUMPFILE_SIGNATURE,
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+           MIN(sizeof mh.signature, sizeof MAKEDUMPFILE_SIGNATURE));
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     mh.type = cpu_to_be64(TYPE_FLAT_HEADER);
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     mh.version = cpu_to_be64(VERSION_FLAT_HEADER);
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-- 
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1.8.3.1
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