Fixed nasty segfault in vasm.c #10785
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radare
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Jul 20, 2018
libr/core/vasm.c
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| @@ -40,7 +42,7 @@ static int readline_callback(void *_a, const char *str) { | |||
| if (a->acode) { | |||
| xlen = strlen (a->acode->buf_hex); | |||
| strcpy (a->codebuf, a->blockbuf); | |||
| memcpy (a->codebuf, a->acode->buf_hex, xlen); | |||
| memcpy (a->codebuf, a->acode->buf_hex, R_MIN (xlen, R_VISUAL_ASM_BUFSIZE - 1)); | |||
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This will not be null terminated. Asan may complain
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Oops, you're totally right ^^ Should be fixed now
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XVilka
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Jul 23, 2018
| strcpy (a->codebuf, a->blockbuf); | ||
| memcpy (a->codebuf, a->acode->buf_hex, xlen); | ||
| if (xlen >= strlen (a->blockbuf)) { |
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This doesn't looks right. It is OOB write if xlen > strlen (a->codebuf). Please handle this case too.
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Thanks to @Maijin that reported it!
This fixes the following segfault:
To reproduce: If you go to visual assemble and type:
jmp $$; jmp $$; jmp $$; ...at the 1100th character typed or so you'll get a buffer overflow and a segfault