fix memory leak of %rep mmacro #73
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When running with -fsanitize=leak enabled nasm prints this error:
Direct leak of 960 byte(s) in 5 object(s) allocated from:
#0 0x7f52b6464a37 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
netwide-assembler#1 0x55cf36676c46 in nasm_calloc nasmlib/alloc.c:72
netwide-assembler#2 0x55cf36676cd1 in nasm_zalloc nasmlib/alloc.c:87
netwide-assembler#3 0x55cf366e3980 in do_directive asm/preproc.c:4754
netwide-assembler#4 0x55cf366fec97 in pp_tokline asm/preproc.c:7773
netwide-assembler#5 0x55cf366ff84a in pp_getline asm/preproc.c:7837
netwide-assembler#6 0x55cf3667263c in assemble_file asm/nasm.c:1722
netwide-assembler#7 0x55cf3666b4e4 in main asm/nasm.c:719
netwide-assembler#8 0x7f52b5b7cd8f in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58
netwide-assembler#9 0x7f52b5b7ce3f in __libc_start_main_impl ../csu/libc-start.c:392
netwide-assembler#10 0x55cf36666e04 in _start (/home/ivan/d/nasm/nasm+0x2e2e04)
This error is reproducible on lnxlinux.asm test or on this
small snippet:
%rep 8
nop
nop
nop
%endrep
The original call to free_mmacro was commented out in
91e7240 as it caused
use-after-free. https://bugzilla.nasm.us/show_bug.cgi?id=3392414
After adding free_mmacro I tested nasm with -fsanitize=address
on all four reproducers attached to the issue and none of them
causes use-after-free now. Also this commit passes all tests
without causing use-after-free.
Signed-off-by: Ivan Sorokin <[email protected]>
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When running with
-fsanitize=leakenabled nasm prints this error:This error is reproducible on
lnxlinux.asmtest or on this small snippet:The original call to free_mmacro was commented out in
91e72409bec0910456e1c34457a04ca00e2f7b99as it caused use-after-free. https://bugzilla.nasm.us/show_bug.cgi?id=3392414After adding
free_mmacroI tested nasm with-fsanitize=addresson all four reproducers attached to the issue and none of them causes use-after-free now. Also this commit passes all tests without causing use-after-free.