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https://github.com/brain-hackers/u-boot-brain
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![]() The hush shell dynamically allocates (and re-allocates) memory for the argument strings in the "char *argv[]" argument vector passed to commands. Any code that modifies these pointers will cause serious corruption of the malloc data structures and crash U-Boot, so make sure the compiler can check that no such modifications are being done by changing the code into "char * const argv[]". This modification is the result of debugging a strange crash caused after adding a new command, which used the following argument processing code which has been working perfectly fine in all Unix systems since version 6 - but not so in U-Boot: int main (int argc, char **argv) { while (--argc > 0 && **++argv == '-') { /* ====> */ while (*++*argv) { switch (**argv) { case 'd': debug++; break; ... default: usage (); } } } ... } The line marked "====>" will corrupt the malloc data structures and usually cause U-Boot to crash when the next command gets executed by the shell. With the modification, the compiler will prevent this with an error: increment of read-only location '*argv' N.B.: The code above can be trivially rewritten like this: while (--argc > 0 && **++argv == '-') { char *arg = *argv; while (*++arg) { switch (*arg) { ... Signed-off-by: Wolfgang Denk <wd@denx.de> Acked-by: Mike Frysinger <vapier@gentoo.org> |
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.. | ||
libfdt | ||
lzma | ||
lzo | ||
addr_map.c | ||
bzlib_crctable.c | ||
bzlib_decompress.c | ||
bzlib_huffman.c | ||
bzlib_private.h | ||
bzlib_randtable.c | ||
bzlib.c | ||
circbuf.c | ||
crc16.c | ||
crc32.c | ||
ctype.c | ||
display_options.c | ||
div64.c | ||
gunzip.c | ||
ldiv.c | ||
lmb.c | ||
Makefile | ||
md5.c | ||
net_utils.c | ||
rbtree.c | ||
sha1.c | ||
sha256.c | ||
string.c | ||
strmhz.c | ||
time.c | ||
vsprintf.c | ||
zlib.c |