mirror of
https://github.com/brain-hackers/u-boot-brain
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54841ab50c
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>
27 lines
587 B
C
27 lines
587 B
C
#ifndef _TYPE_BEDBUG_H
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#define _TYPE_BEDBUG_H
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/* Supporting routines */
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int bedbug_puts (const char *);
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void bedbug_init (void);
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void bedbug860_init (void);
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void do_bedbug_breakpoint (struct pt_regs *);
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void bedbug_main_loop (unsigned long, struct pt_regs *);
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typedef struct {
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int hw_debug_enabled;
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int stopped;
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int current_bp;
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struct pt_regs *regs;
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void (*do_break) (cmd_tbl_t *, int, int, char * const []);
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void (*break_isr) (struct pt_regs *);
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int (*find_empty) (void);
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int (*set) (int, unsigned long);
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int (*clear) (int);
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} CPU_DEBUG_CTX;
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#endif /* _TYPE_BEDBUG_H */
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