From: Tom Rix <[email protected]>
clang static analysis flags this error
lib/decompress_bunzip2.c:671:13: warning: Result of 'malloc' is converted
to a pointer of type 'unsigned int', which is incompatible with sizeof
operand type 'int' [unix.MallocSizeof]
bd->dbuf = large_malloc(bd->dbufSize * sizeof(int));
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Reviewing the bunzip_data structure, the element dbuf is type
/* Intermediate buffer and its size (in bytes) */
unsigned int *dbuf, dbufSize;
So change the type in sizeof to 'unsigned int'
Fixes: bc22c17e12c1 ("bzip2/lzma: library support for gzip, bzip2 and lzma decompression")
Signed-off-by: Tom Rix <[email protected]>
---
lib/decompress_bunzip2.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lib/decompress_bunzip2.c b/lib/decompress_bunzip2.c
index 7c4932eed748..59ab76bda7a7 100644
--- a/lib/decompress_bunzip2.c
+++ b/lib/decompress_bunzip2.c
@@ -668,7 +668,7 @@ static int INIT start_bunzip(struct bunzip_data **bdp, void *inbuf, long len,
uncompressed data. Allocate intermediate buffer for block. */
bd->dbufSize = 100000*(i-BZh0);
- bd->dbuf = large_malloc(bd->dbufSize * sizeof(int));
+ bd->dbuf = large_malloc(bd->dbufSize * sizeof(unsigned int));
if (!bd->dbuf)
return RETVAL_OUT_OF_MEMORY;
return RETVAL_OK;
--
2.18.1
On 2020-07-12 05:59, [email protected] wrote:
> From: Tom Rix <[email protected]>
>
> clang static analysis flags this error
>
> lib/decompress_bunzip2.c:671:13: warning: Result of 'malloc' is converted
> to a pointer of type 'unsigned int', which is incompatible with sizeof
> operand type 'int' [unix.MallocSizeof]
> bd->dbuf = large_malloc(bd->dbufSize * sizeof(int));
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> Reviewing the bunzip_data structure, the element dbuf is type
>
> /* Intermediate buffer and its size (in bytes) */
> unsigned int *dbuf, dbufSize;
>
> So change the type in sizeof to 'unsigned int'
>
You must be kidding.
If you want to change it, change it to sizeof(bd->dbuf) instead, but this flag
is at least in my opinion a total joke. For sizeof(int) != sizeof(unsigned
int) is beyond bizarre, no matter how stupid the platform.
-hpa
On 7/12/20 6:09 AM, H. Peter Anvin wrote:
> On 2020-07-12 05:59, [email protected] wrote:
>> From: Tom Rix <[email protected]>
>>
>> clang static analysis flags this error
>>
>> lib/decompress_bunzip2.c:671:13: warning: Result of 'malloc' is converted
>> to a pointer of type 'unsigned int', which is incompatible with sizeof
>> operand type 'int' [unix.MallocSizeof]
>> bd->dbuf = large_malloc(bd->dbufSize * sizeof(int));
>> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>
>> Reviewing the bunzip_data structure, the element dbuf is type
>>
>> /* Intermediate buffer and its size (in bytes) */
>> unsigned int *dbuf, dbufSize;
>>
>> So change the type in sizeof to 'unsigned int'
>>
> You must be kidding.
>
> If you want to change it, change it to sizeof(bd->dbuf) instead, but this flag
> is at least in my opinion a total joke. For sizeof(int) != sizeof(unsigned
> int) is beyond bizarre, no matter how stupid the platform.
Using the actual type is more correct that using a type of the same size.
trix
> -hpa
>
On Sun, 2020-07-12 at 08:12 -0700, Tom Rix wrote:
> On 7/12/20 6:09 AM, H. Peter Anvin wrote:
> > On 2020-07-12 05:59, [email protected] wrote:
> > > From: Tom Rix <[email protected]>
[]
> > > So change the type in sizeof to 'unsigned int'
> > You must be kidding.
> >
> > If you want to change it, change it to sizeof(bd->dbuf) instead, but this flag
> > is at least in my opinion a total joke. For sizeof(int) != sizeof(unsigned
> > int) is beyond bizarre, no matter how stupid the platform.
>
> Using the actual type is more correct that using a type of the same size.
Sure.
But this hardly matters as this same type conversion
from signed to unsigned or the other way round is
_everywhere_ in the kernel.
And especially the cc of stable is unnecessary.
On July 12, 2020 8:12:43 AM PDT, Tom Rix <[email protected]> wrote:
>
>On 7/12/20 6:09 AM, H. Peter Anvin wrote:
>> On 2020-07-12 05:59, [email protected] wrote:
>>> From: Tom Rix <[email protected]>
>>>
>>> clang static analysis flags this error
>>>
>>> lib/decompress_bunzip2.c:671:13: warning: Result of 'malloc' is
>converted
>>> to a pointer of type 'unsigned int', which is incompatible with
>sizeof
>>> operand type 'int' [unix.MallocSizeof]
>>> bd->dbuf = large_malloc(bd->dbufSize * sizeof(int));
>>> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>>
>>> Reviewing the bunzip_data structure, the element dbuf is type
>>>
>>> /* Intermediate buffer and its size (in bytes) */
>>> unsigned int *dbuf, dbufSize;
>>>
>>> So change the type in sizeof to 'unsigned int'
>>>
>> You must be kidding.
>>
>> If you want to change it, change it to sizeof(bd->dbuf) instead, but
>this flag
>> is at least in my opinion a total joke. For sizeof(int) !=
>sizeof(unsigned
>> int) is beyond bizarre, no matter how stupid the platform.
>
>Using the actual type is more correct that using a type of the same
>size.
>
>trix
>
>> -hpa
>>
"More correct?" All it is is more verbose.
Using the sizeof of the actual object at least adds some actual safety.
--
Sent from my Android device with K-9 Mail. Please excuse my brevity.
On 7/12/20 3:21 PM, [email protected] wrote:
> On July 12, 2020 8:12:43 AM PDT, Tom Rix <[email protected]> wrote:
>> On 7/12/20 6:09 AM, H. Peter Anvin wrote:
>>> On 2020-07-12 05:59, [email protected] wrote:
>>>> From: Tom Rix <[email protected]>
>>>>
>>>> clang static analysis flags this error
>>>>
>>>> lib/decompress_bunzip2.c:671:13: warning: Result of 'malloc' is
>> converted
>>>> to a pointer of type 'unsigned int', which is incompatible with
>> sizeof
>>>> operand type 'int' [unix.MallocSizeof]
>>>> bd->dbuf = large_malloc(bd->dbufSize * sizeof(int));
>>>> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>>>
>>>> Reviewing the bunzip_data structure, the element dbuf is type
>>>>
>>>> /* Intermediate buffer and its size (in bytes) */
>>>> unsigned int *dbuf, dbufSize;
>>>>
>>>> So change the type in sizeof to 'unsigned int'
>>>>
>>> You must be kidding.
>>>
>>> If you want to change it, change it to sizeof(bd->dbuf) instead, but
>> this flag
>>> is at least in my opinion a total joke. For sizeof(int) !=
>> sizeof(unsigned
>>> int) is beyond bizarre, no matter how stupid the platform.
>> Using the actual type is more correct that using a type of the same
>> size.
>>
>> trix
>>
>>> -hpa
>>>
> "More correct?" All it is is more verbose.
>
> Using the sizeof of the actual object at least adds some actual safety.
Sorry, I am being pedantic, I mean anything that produces the correct assembly is correct. But there are different path to being correct. The path I was suggesting to follow the type of the element/final pointer when allocating an memory.
large_malloc(bd->dbufSize * sizeof(*bd->dbuf)) would also work
I will respin.
trix
On July 13, 2020 12:27:02 PM PDT, Tom Rix <[email protected]> wrote:
>
>On 7/12/20 3:21 PM, [email protected] wrote:
>> On July 12, 2020 8:12:43 AM PDT, Tom Rix <[email protected]> wrote:
>>> On 7/12/20 6:09 AM, H. Peter Anvin wrote:
>>>> On 2020-07-12 05:59, [email protected] wrote:
>>>>> From: Tom Rix <[email protected]>
>>>>>
>>>>> clang static analysis flags this error
>>>>>
>>>>> lib/decompress_bunzip2.c:671:13: warning: Result of 'malloc' is
>>> converted
>>>>> to a pointer of type 'unsigned int', which is incompatible with
>>> sizeof
>>>>> operand type 'int' [unix.MallocSizeof]
>>>>> bd->dbuf = large_malloc(bd->dbufSize * sizeof(int));
>>>>> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>>>>
>>>>> Reviewing the bunzip_data structure, the element dbuf is type
>>>>>
>>>>> /* Intermediate buffer and its size (in bytes) */
>>>>> unsigned int *dbuf, dbufSize;
>>>>>
>>>>> So change the type in sizeof to 'unsigned int'
>>>>>
>>>> You must be kidding.
>>>>
>>>> If you want to change it, change it to sizeof(bd->dbuf) instead,
>but
>>> this flag
>>>> is at least in my opinion a total joke. For sizeof(int) !=
>>> sizeof(unsigned
>>>> int) is beyond bizarre, no matter how stupid the platform.
>>> Using the actual type is more correct that using a type of the same
>>> size.
>>>
>>> trix
>>>
>>>> -hpa
>>>>
>> "More correct?" All it is is more verbose.
>>
>> Using the sizeof of the actual object at least adds some actual
>safety.
>
>Sorry, I am being pedantic, I mean anything that produces the correct
>assembly is correct. But there are different path to being correct.
>The path I was suggesting to follow the type of the element/final
>pointer when allocating an memory.
>
>large_malloc(bd->dbufSize * sizeof(*bd->dbuf)) would also work
>
>I will respin.
>
>trix
This isn't Linux style, but in the NASM source I have been migrating to macros:
nasm_new(ptr);
nasm_newn(ptr,n);
... using sizeof() in exactly this manner.
--
Sent from my Android device with K-9 Mail. Please excuse my brevity.