forked from luck/tmp_suning_uos_patched
99ce7962d5
Linus reported that GCC-7.3 generated a switch-table construct that confused objtool. It turns out that, in particular due to KASAN, it is possible to have unrelated .rodata usage in between the .rodata setup for the switch-table and the following indirect jump. The simple linear reverse search from the indirect jump would hit upon the KASAN .rodata usage first and fail to find a switch_table, resulting in a spurious 'sibling call with modified stack frame' warning. Fix this by creating a 'jump-stack' which we can 'unwind' during reversal, thereby skipping over much of the in-between code. This is not fool proof by any means, but is sufficient to make the known cases work. Future work would be to construct more comprehensive flow analysis code. Reported-and-tested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180208130232.GF25235@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org> |
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| .. | ||
| arch/x86 | ||
| Documentation | ||
| .gitignore | ||
| arch.h | ||
| Build | ||
| builtin-check.c | ||
| builtin-orc.c | ||
| builtin.h | ||
| cfi.h | ||
| check.c | ||
| check.h | ||
| elf.c | ||
| elf.h | ||
| Makefile | ||
| objtool.c | ||
| orc_dump.c | ||
| orc_gen.c | ||
| orc.h | ||
| special.c | ||
| special.h | ||
| sync-check.sh | ||
| warn.h | ||