[2.6.38-rc6] build:mkpiggy fixlet...

[2.6.38-rc6] build:mkpiggy fixlet...

[Daniel J Blueman]

Ensure build doesn't silently continue despite read failure,
addressing a warning due to the unchecked call.

Signed-off-by: Daniel J Blueman <daniel.blueman@gmail.com>

diff --git a/arch/x86/boot/compressed/mkpiggy.c
b/arch/x86/boot/compressed/mkpiggy.c
index 646aa78..845a1f8 100644
--- a/arch/x86/boot/compressed/mkpiggy.c
+++ b/arch/x86/boot/compressed/mkpiggy.c
@@ -62,7 +62,12 @@ int main(int argc, char *argv[])
 	if (fseek(f, -4L, SEEK_END)) {
 		perror(argv[1]);
 	}
-	fread(&olen, sizeof olen, 1, f);
+
+	if (fread(&olen, sizeof(olen), 1, f) != 1) {
+		perror(argv[1]);
+		return 1;
+	}
+		
 	ilen = ftell(f);
 	olen = getle32(&olen);
 	fclose(f);
-- 
Daniel J Blueman

Re: [2.6.38-rc6] build:mkpiggy fixlet...

[Américo Wang]

On Wed, Feb 23, 2011 at 09:33:59AM +0800, Daniel J Blueman wrote:
>Ensure build doesn't silently continue despite read failure,
>addressing a warning due to the unchecked call.
>
>Signed-off-by: Daniel J Blueman <daniel.blueman@gmail.com>
>
>diff --git a/arch/x86/boot/compressed/mkpiggy.c
>b/arch/x86/boot/compressed/mkpiggy.c
>index 646aa78..845a1f8 100644
>--- a/arch/x86/boot/compressed/mkpiggy.c
>+++ b/arch/x86/boot/compressed/mkpiggy.c
>@@ -62,7 +62,12 @@ int main(int argc, char *argv[])
> 	if (fseek(f, -4L, SEEK_END)) {
> 		perror(argv[1]);
> 	}
>-	fread(&olen, sizeof olen, 1, f);
>+
>+	if (fread(&olen, sizeof(olen), 1, f) != 1) {
>+		perror(argv[1]);
>+		return 1;


You need to close the file here...


>+	}
>+		
> 	ilen = ftell(f);
> 	olen = getle32(&olen);
> 	fclose(f);

Thanks.

Re: [2.6.38-rc6] build:mkpiggy fixlet...

[Daniel J Blueman]

On 1 March 2011 00:25, Américo Wang <xiyou.wangcong@gmail.com> wrote:
> On Wed, Feb 23, 2011 at 09:33:59AM +0800, Daniel J Blueman wrote:
>>Ensure build doesn't silently continue despite read failure,
>>addressing a warning due to the unchecked call.
>>
>>Signed-off-by: Daniel J Blueman <daniel.blueman@gmail.com>
>>
>>diff --git a/arch/x86/boot/compressed/mkpiggy.c
>>b/arch/x86/boot/compressed/mkpiggy.c
>>index 646aa78..845a1f8 100644
>>--- a/arch/x86/boot/compressed/mkpiggy.c
>>+++ b/arch/x86/boot/compressed/mkpiggy.c
>>@@ -62,7 +62,12 @@ int main(int argc, char *argv[])
>>       if (fseek(f, -4L, SEEK_END)) {
>>               perror(argv[1]);
>>       }
>>-      fread(&olen, sizeof olen, 1, f);
>>+
>>+      if (fread(&olen, sizeof(olen), 1, f) != 1) {
>>+              perror(argv[1]);
>>+              return 1;
>
> You need to close the file here...

I could close the file here to be polite, but since the program is
exiting, the OS will close the file.

I added the error path in a way consistent with the following error
path - perhaps better than a more intrusive patch to handle everything
gracefully; it just fixes the bug (ie silent failure) and isn't a
cleanup.

>>+      }
>>+
>>       ilen = ftell(f);
>>       olen = getle32(&olen);
>>       fclose(f);
-- 
Daniel J Blueman

[tip:x86/urgent] x86, build: Make sure mkpiggy fails on read error

[tip-bot for Daniel J Blueman]

Commit-ID:  6670e9cdaf554290e26121aa72f0118f2fac52e5
Gitweb:     http://git.kernel.org/tip/6670e9cdaf554290e26121aa72f0118f2fac52e5
Author:     Daniel J Blueman <daniel.blueman@gmail.com>
AuthorDate: Wed, 23 Feb 2011 09:33:59 +0800
Committer:  H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Tue, 1 Mar 2011 16:32:03 -0800

x86, build: Make sure mkpiggy fails on read error

Ensure build doesn't silently continue despite read failure,
addressing a warning due to the unchecked call.

Signed-off-by: Daniel J Blueman <daniel.blueman@gmail.com>
LKML-Reference: <AANLkTimxxTMU3=4ry-_zbY6v1xiDi+hW9y1RegTr8vLK@mail.gmail.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/boot/compressed/mkpiggy.c |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/arch/x86/boot/compressed/mkpiggy.c b/arch/x86/boot/compressed/mkpiggy.c
index 646aa78..46a8238 100644
--- a/arch/x86/boot/compressed/mkpiggy.c
+++ b/arch/x86/boot/compressed/mkpiggy.c
@@ -62,7 +62,12 @@ int main(int argc, char *argv[])
 	if (fseek(f, -4L, SEEK_END)) {
 		perror(argv[1]);
 	}
-	fread(&olen, sizeof olen, 1, f);
+
+	if (fread(&olen, sizeof(olen), 1, f) != 1) {
+		perror(argv[1]);
+		return 1;
+	}
+
 	ilen = ftell(f);
 	olen = getle32(&olen);
 	fclose(f);