a13bb127d2
need this. Consider the following code: case 'O': output_filename = malloc(strlen(arg)+4); strcpy(output_filename, arg); strcat(output_filename, ".tmp"); real_output_filename = arg; return; The idea here is to malloc() a buffer big enough to hold the name of a supplied file name, plus ".tmp". So we malloc() 'size of filename' bytes plus 4, right? Wrong! ".tmp" is _FIVE_ bytes long! There's a traling '\0' which strcat() gleefully tacks on _outside_ the bounds of the buffer. Result: program corrupts own memory. Program SEGVs at seemingly random times. Bill not like random SEGVs. Bill smash. Know how I found this? I've been trying to bootstrap -current on my 2.1.0-RELEASE machine at work and I couldn't seem to get libc.a built because the linker would intermittently blow chunks while executing things like 'ld -O foo.o -X -r foo.o'. Since this is an initial bootstrap version of ld, it was linked against the 2.1.0 libc, who's malloc() behaves differently than that in -current. Presumeably ld -O doesn't blow up in -current, otherwise someone would have spotted this already. I don't know if this is a bug or a feature. Anyway. I'm changing the strlen(arg)+4 to strlen(arg)+5. Bah. |
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| .. | ||
| gnu2bmake | ||
| include | ||
| lib | ||
| libexec | ||
| usr.bin | ||
| usr.sbin | ||
| COPYING | ||
| COPYING.LIB | ||
| Makefile | ||