[PATCH 0/2] apparmor unaligned memory fixes

Helge Deller deller at gmx.de
Wed Nov 26 16:58:55 UTC 2025


On 11/26/25 17:16, John Paul Adrian Glaubitz wrote:
> Hi Helge,
> 
> On Wed, 2025-11-26 at 12:31 +0100, Helge Deller wrote:
>> Like this (untested!) patch:
>>
>> [PATCH] apparmor: Optimize table creation from possibly unaligned memory
>>
>> Source blob may come from userspace and might be unaligned.
>> Try to optize the copying process by avoiding unaligned memory accesses.
>>
>> Signed-off-by: Helge Deller <deller at gmx.de>
>>
>> diff --git a/security/apparmor/include/match.h b/security/apparmor/include/match.h
>> index 1fbe82f5021b..225df6495c84 100644
>> --- a/security/apparmor/include/match.h
>> +++ b/security/apparmor/include/match.h
>> @@ -111,9 +111,14 @@ struct aa_dfa {
>>   		typeof(LEN) __i; \
>>   		TTYPE *__t = (TTYPE *) TABLE; \
>>   		BTYPE *__b = (BTYPE *) BLOB; \
>> -		for (__i = 0; __i < LEN; __i++) { \
>> -			__t[__i] = NTOHX(__b[__i]); \
>> -		} \
>> +		BUILD_BUG_ON(sizeof(TTYPE) != sizeof(BTYPE)); \
>> +		/* copy to naturally aligned table address */ \
>> +		memcpy(__t, __b, (LEN) * sizeof(BTYPE)); \
>> +		/* convert from big-endian if necessary */ \
>> +		if (!IS_ENABLED(CONFIG_CPU_BIG_ENDIAN)) \
>> +			for (__i = 0; __i < LEN; __i++, __t++) { \
>> +				*__t = NTOHX(*__t); \
>> +			} \
>>   	} while (0)
>>   
>>   static inline size_t table_size(size_t len, size_t el_size)
> 
> So, is this patch supposed to replace all the other proposed patches?

It just replaces the patch from John.
But please test the v2 patch I sent instead...

Helge



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