ACPR/android_system_core
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Merge "Improve the crasher stack-overflow command."

Browse source
This commit is contained in:
Elliott Hughes 2013-07-16 17:19:57 +00:00 • committed by Gerrit Code Review
commit 596ee9ea8a
1 changed files with 4 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
debuggerd/crasher.c
View file

@ -47,17 +47,19 @@ static int smash_stack(int i) {
// Unless there's a "big enough" buffer on the stack, gcc // Unless there's a "big enough" buffer on the stack, gcc
// doesn't bother inserting checks. // doesn't bother inserting checks.
char buf[8]; char buf[8];
// If we don't write something relatively unpredicatable // If we don't write something relatively unpredictable
// into the buffer and then do something with it, gcc // into the buffer and then do something with it, gcc
// optimizes everything away and just returns a constant. // optimizes everything away and just returns a constant.
*(int*)(&buf[7]) = (uintptr_t) &buf[0]; *(int*)(&buf[7]) = (uintptr_t) &buf[0];
return *(int*)(&buf[0]); return *(int*)(&buf[0]);
} }
static void* global = 0; // So GCC doesn't optimize the tail recursion out of overflow_stack.
__attribute__((noinline)) static void overflow_stack(void* p) { __attribute__((noinline)) static void overflow_stack(void* p) {
fprintf(stderr, "p = %p\n", p);
void* buf[1]; void* buf[1];
buf[0] = p; buf[0] = p;
global = buf;
overflow_stack(&buf); overflow_stack(&buf);
} }