OpenFEC fails to perform on 32bit platforms

[baranovmv]

In case of compiling OpenFEC with -m32 flag or compiling and calling on ARM tests fail.
The issue is in file of_symbol.c in symbols arithmetic operations.

==29720== Memcheck, a memory error detector
==29720== Copyright (C) 2002-2013, and GNU GPL'd, by Julian Seward et al.
==29720== Using Valgrind-3.10.1 and LibVEX; rerun with -h for copyright info
==29720== Command: ./eperftool -codec=3 -seed=1 -find_min_overhead -tot_src=39 -tot_rep=23
==29720== 
./eperftooleperf_tool: an extended AL-FEC performance evaluation tool
OpenFEC.org - Version 1.4.2, December 16th, 2014

tot_nb_source_symbols=39  tot_nb_repair_symbols=23  symbol_size=1024  ldpc_N1=5  rs_m=8
codec_id=3
transmission_type=randomly_send_all_source_and_repair_symbols
===> (1) test with 39 recvd symbols (overhead 0) and 23 lost symbols... ==29720== Invalid read of size 4
==29720==    at 0x403B43E: of_add_to_multiple_symbols (of_symbol.c:502)
==29720==    by 0x403D3C1: of_linear_binary_code_col_forward_elimination (of_ml_tool.c:257)
==29720==    by 0x403CF58: of_linear_binary_code_triangularize_dense_system (of_ml_tool.c:145)
==29720==    by 0x403CD99: of_linear_binary_code_solve_dense_system (of_ml_tool.c:111)
==29720==    by 0x403BBBA: of_linear_binary_code_finish_decoding_with_ml (of_ml_decoding.c:227)
==29720==    by 0x404912D: of_ldpc_staircase_finish_decoding (of_ldpc_staircase_api.c:465)
==29720==    by 0x4046DA4: of_finish_decoding (of_openfec_api.c:568)
==29720==    by 0x804BE16: receive_and_decode (receiver.c:209)
==29720==    by 0x804B0C5: start_enc_dec_test (eperftool.c:268)
==29720==    by 0x804AB43: main (eperftool.c:124)
==29720==  Address 0x4307d78 is 0 bytes after a block of size 248 alloc'd
==29720==    at 0x402A17C: malloc (in /usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==29720==    by 0x40456C0: of_malloc (of_mem.c:40)
==29720==    by 0x40488E5: of_ldpc_staircase_set_fec_parameters (of_ldpc_staircase_api.c:291)
==29720==    by 0x4045F5C: of_set_fec_parameters (of_openfec_api.c:213)
==29720==    by 0x804F8E9: create_and_init_codec_instance (codec_instance_mgmt.c:107)
==29720==    by 0x804BAB4: receive_and_decode (receiver.c:148)
==29720==    by 0x804B0C5: start_enc_dec_test (eperftool.c:268)
==29720==    by 0x804AB43: main (eperftool.c:124)
==29720== 
==29720== Invalid write of size 4
==29720==    at 0x403B44A: of_add_to_multiple_symbols (of_symbol.c:502)
==29720==    by 0x403D3C1: of_linear_binary_code_col_forward_elimination (of_ml_tool.c:257)
==29720==    by 0x403CF58: of_linear_binary_code_triangularize_dense_system (of_ml_tool.c:145)
==29720==    by 0x403CD99: of_linear_binary_code_solve_dense_system (of_ml_tool.c:111)
==29720==    by 0x403BBBA: of_linear_binary_code_finish_decoding_with_ml (of_ml_decoding.c:227)
==29720==    by 0x404912D: of_ldpc_staircase_finish_decoding (of_ldpc_staircase_api.c:465)
==29720==    by 0x4046DA4: of_finish_decoding (of_openfec_api.c:568)
==29720==    by 0x804BE16: receive_and_decode (receiver.c:209)
==29720==    by 0x804B0C5: start_enc_dec_test (eperftool.c:268)
==29720==    by 0x804AB43: main (eperftool.c:124)
==29720==  Address 0x4307d78 is 0 bytes after a block of size 248 alloc'd
==29720==    at 0x402A17C: malloc (in /usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==29720==    by 0x40456C0: of_malloc (of_mem.c:40)
==29720==    by 0x40488E5: of_ldpc_staircase_set_fec_parameters (of_ldpc_staircase_api.c:291)
==29720==    by 0x4045F5C: of_set_fec_parameters (of_openfec_api.c:213)
==29720==    by 0x804F8E9: create_and_init_codec_instance (codec_instance_mgmt.c:107)
==29720==    by 0x804BAB4: receive_and_decode (receiver.c:148)
==29720==    by 0x804B0C5: start_enc_dec_test (eperftool.c:268)
==29720==    by 0x804AB43: main (eperftool.c:124)
==29720== 
==29720== Invalid read of size 4
==29720==    at 0x403B359: of_add_from_multiple_symbols (of_symbol.c:255)
==29720==    by 0x403D6BC: of_linear_binary_code_backward_substitution (of_ml_tool.c:322)
==29720==    by 0x403CE37: of_linear_binary_code_solve_dense_system (of_ml_tool.c:119)
==29720==    by 0x403BBBA: of_linear_binary_code_finish_decoding_with_ml (of_ml_decoding.c:227)
==29720==    by 0x404912D: of_ldpc_staircase_finish_decoding (of_ldpc_staircase_api.c:465)
==29720==    by 0x4046DA4: of_finish_decoding (of_openfec_api.c:568)
==29720==    by 0x804BE16: receive_and_decode (receiver.c:209)
==29720==    by 0x804B0C5: start_enc_dec_test (eperftool.c:268)
==29720==    by 0x804AB43: main (eperftool.c:124)
==29720==  Address 0x4307d78 is 0 bytes after a block of size 248 alloc'd
==29720==    at 0x402A17C: malloc (in /usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==29720==    by 0x40456C0: of_malloc (of_mem.c:40)
==29720==    by 0x40488E5: of_ldpc_staircase_set_fec_parameters (of_ldpc_staircase_api.c:291)
==29720==    by 0x4045F5C: of_set_fec_parameters (of_openfec_api.c:213)
==29720==    by 0x804F8E9: create_and_init_codec_instance (codec_instance_mgmt.c:107)
==29720==    by 0x804BAB4: receive_and_decode (receiver.c:148)
==29720==    by 0x804B0C5: start_enc_dec_test (eperftool.c:268)
==29720==    by 0x804AB43: main (eperftool.c:124)
==29720== 
ERROR in "/opt/openfec/applis/eperftool/receiver.c":307:receive_and_decode(): ERROR in "/opt/openfec/applis/eperftool/receiver.c":307:receive_and_decode(): ERROR in "/opt/openfec/applis/eperftool/receiver.c":307:receive_and_decode(): ERROR in "/opt/openfec/applis/eperftool/receiver.c":307:receive_and_decode(): ERROR in "/opt/openfec/applis/eperftool/receiver.c":307:receive_and_decode(): ERROR in "/opt/openfec/applis/eperftool/receiver.c":307:receive_and_decode(): ERROR in "/opt/openfec/applis/eperftool/receiver.c":307:receive_and_decode(): ERROR in "/opt/openfec/applis/eperftool/receiver.c":307:receive_and_decode(): ERROR in "/opt/openfec/applis/eperftool/receiver.c":307:receive_and_decode(): ERROR in "/opt/openfec/applis/eperftool/receiver.c":307:receive_and_decode(): ERROR in "/opt/openfec/applis/eperftool/receiver.c":307:receive_and_decode(): ERROR in "/opt/openfec/applis/eperftool/receiver.c":307:receive_and_decode(): ERROR in "/opt/openfec/applis/eperftool/receiver.c":307:receive_and_decode(): ERROR in "/opt/openfec/applis/eperftool/eperftool.c":274:start_enc_dec_test():    failed
decoding_status=2
==29720== 
==29720== HEAP SUMMARY:
==29720==     in use at exit: 0 bytes in 0 blocks
==29720==   total heap usage: 147 allocs, 147 frees, 185,502 bytes allocated
==29720== 
==29720== All heap blocks were freed -- no leaks are possible
==29720== 
==29720== For counts of detected and suppressed errors, rerun with: -v
==29720== ERROR SUMMARY: 432 errors from 3 contexts (suppressed: 0 from 0)

[baranovmv]

One can reproduce this on on x86-64 host by adding the following string in CMakeLists.txt:

set(CMAKE_C_FLAGS "-m32")

[gavv]

We need this for #9.

[baranovmv]

According to OpenFEC tests (make test) the issue is in of_add_to_multiple_symbols(...) and of_add_from_multiple_symbols(...)

[baranovmv]

This patch upon src/lib_common/linear_binary_codes_utils/of_symbol.c fix this issue

--- src/lib_common/linear_binary_codes_utils/of_symbol.c        2014-12-16 17:29:00.000000000 +0300
+++ src/lib_common/linear_binary_codes_utils/of_symbol.c        2016-05-15 14:42:45.821633790 +0300
@@ -244,11 +244,14 @@ void      of_add_from_multiple_symbols    (void

 #else //defined (__LP64__) || (__WORDSIZE == 64) } {

+       while(from_size > 0) {
        /*
         * 32-bit machines
         */
        UINT32          *t32 = (UINT32*) to;    // to pointer to 32-bit integers
-       UINT32          *f32 = (UINT32*)  from; // from pointer to 32-bit integers
+               UINT32          *f32 = (UINT32*)  from[0];      // from pointer to 32-bit integers
+               from++ ;
+               from_size-- ;
        /* First perform as many 32-bit XORs as needed... */
        for (i = symbolSize32; i > 0; i--)
        {
@@ -265,6 +268,7 @@ void        of_add_from_multiple_symbols    (void
                        * (UINT8*) ( (UINT8*) t32 + i) ^= * (UINT8*) ( (UINT8*) f32 + i);
                }
        }
+       }
 #endif //defined (__LP64__) || (__WORDSIZE == 64) }

 //#else  /* } ASSEMBLY_SSE_OPT { */
@@ -494,8 +498,11 @@ void       of_add_to_multiple_symbols      (void           *
        /*
         * 32-bit machines
         */
-       UINT32          *t32 = (UINT32*) to;    // to pointer to 32-bit integers
+       while( to_size > 0 ){
+               UINT32          *t32 = (UINT32*) to[0]; // to pointer to 32-bit integers
        UINT32          *f32 = (UINT32*)  from; // from pointer to 32-bit integers
+               to++ ;
+               to_size-- ;
        /* First perform as many 32-bit XORs as needed... */
        for (i = symbolSize32; i > 0; i--)
        {
@@ -512,6 +519,7 @@ void        of_add_to_multiple_symbols      (void           *
                        * (UINT8*) ( (UINT8*) t32 + i) ^= * (UINT8*) ( (UINT8*) f32 + i);
                }
        }
+       }
 #endif //defined (__LP64__) || (__WORDSIZE == 64) }

        //#else  /* } ASSEMBLY_SSE_OPT { */

[gavv]

The patch has troubles with whitespaces and formatting. I've uploaded fixed verson: gist.

[gavv]

Our travis now also cross-compiles Roc for RPi 1 and RPi 2 and runs tests using QEMU.

To fix builds, I temporarily added applying the patch above to scons --with-3rdparty=openfec. We can remove it when the patch will be accepted by upstream.