diff options
Diffstat (limited to 'libdwfl')
| -rw-r--r-- | libdwfl/dwfl_frame.c | 3 | ||||
| -rw-r--r-- | libdwfl/frame_unwind.c | 46 | ||||
| -rw-r--r-- | libdwfl/libdwflP.h | 7 |
3 files changed, 38 insertions, 18 deletions
diff --git a/libdwfl/dwfl_frame.c b/libdwfl/dwfl_frame.c index 28008e90..89fd9205 100644 --- a/libdwfl/dwfl_frame.c +++ b/libdwfl/dwfl_frame.c @@ -1,5 +1,5 @@ /* Get Dwarf Frame state for target PID or core file. - Copyright (C) 2013 Red Hat, Inc. + Copyright (C) 2013-2014 Red Hat, Inc. This file is part of elfutils. This file is free software; you can redistribute it and/or modify @@ -98,6 +98,7 @@ state_alloc (Dwfl_Thread *thread) state->thread = thread; state->signal_frame = false; state->initial_frame = true; + state->cfa = 0; state->pc_state = DWFL_FRAME_STATE_ERROR; memset (state->regs_set, 0, sizeof (state->regs_set)); thread->unwound = state; diff --git a/libdwfl/frame_unwind.c b/libdwfl/frame_unwind.c index 3ce45479..d434c468 100644 --- a/libdwfl/frame_unwind.c +++ b/libdwfl/frame_unwind.c @@ -1,5 +1,5 @@ /* Get previous frame state for an existing frame state. - Copyright (C) 2013 Red Hat, Inc. + Copyright (C) 2013-2014 Red Hat, Inc. This file is part of elfutils. This file is free software; you can redistribute it and/or modify @@ -105,8 +105,8 @@ bra_compar (const void *key_voidp, const void *elem_voidp) DW_OP_call_frame_cfa is no longer permitted. */ static bool -expr_eval (Dwfl_Frame *state, Dwarf_Frame *frame, const Dwarf_Op *ops, - size_t nops, Dwarf_Addr *result, Dwarf_Addr bias) +expr_eval (Dwfl_Frame *state, const Dwarf_Op *ops, size_t nops, + Dwarf_Addr *result, Dwarf_Addr bias, const int elfclass) { Dwfl_Process *process = state->thread->process; if (nops == 0) @@ -310,7 +310,6 @@ expr_eval (Dwfl_Frame *state, Dwarf_Frame *frame, const Dwarf_Op *ops, } if (op->atom == DW_OP_deref_size) { - const int elfclass = frame->cache->e_ident[EI_CLASS]; const unsigned addr_bytes = elfclass == ELFCLASS32 ? 4 : 8; if (op->number > addr_bytes) { @@ -450,16 +449,15 @@ expr_eval (Dwfl_Frame *state, Dwarf_Frame *frame, const Dwarf_Op *ops, break; /* DW_OP_* not listed in libgcc/unwind-dw2.c execute_stack_op: */ case DW_OP_call_frame_cfa:; - // Not used by CFI itself but it is synthetized by elfutils internation. - Dwarf_Op *cfa_ops; - size_t cfa_nops; - Dwarf_Addr cfa; - if (frame == NULL - || dwarf_frame_cfa (frame, &cfa_ops, &cfa_nops) != 0 - || ! expr_eval (state, NULL, cfa_ops, cfa_nops, &cfa, bias) - || ! push (cfa)) - { - __libdwfl_seterrno (DWFL_E_LIBDW); + if (state->unwound->cfa == 0) + { + /* DW_OP_call_frame_cfa is needed to compute CFA itself. */ + free (stack); + __libdwfl_seterrno (DWFL_E_INVALID_DWARF); + return false; + } + if (! push (state->unwound->cfa)) + { free (stack); return false; } @@ -510,6 +508,7 @@ new_unwound (Dwfl_Frame *state) unwound->unwound = NULL; unwound->signal_frame = false; unwound->initial_frame = false; + unwound->cfa = 0; unwound->pc_state = DWFL_FRAME_STATE_ERROR; memset (unwound->regs_set, 0, sizeof (unwound->regs_set)); } @@ -536,12 +535,29 @@ handle_cfi (Dwfl_Frame *state, Dwarf_Addr pc, Dwarf_CFI *cfi, Dwarf_Addr bias) Ebl *ebl = process->ebl; size_t nregs = ebl_frame_nregs (ebl); assert (nregs > 0); + const int elfclass = frame->cache->e_ident[EI_CLASS]; /* The return register is special for setting the unwound->pc_state. */ unsigned ra = frame->fde->cie->return_address_register; bool ra_set = false; ebl_dwarf_to_regno (ebl, &ra); + // Set unwound->CFA. + Dwarf_Op *cfa_ops; + size_t cfa_nops; + if (dwarf_frame_cfa (frame, &cfa_ops, &cfa_nops) != 0 + || ! expr_eval (state, cfa_ops, cfa_nops, &unwound->cfa, bias, elfclass)) + { + __libdwfl_seterrno (DWFL_E_LIBDW); + return; + } + if (unwound->cfa == 0 + || (! state->initial_frame && unwound->cfa <= state->cfa)) + { + __libdwfl_seterrno (DWFL_E_UNWIND_BAD_CFA); + return; + } + for (unsigned regno = 0; regno < nregs; regno++) { Dwarf_Op reg_ops_mem[3], *reg_ops; @@ -574,7 +590,7 @@ handle_cfi (Dwfl_Frame *state, Dwarf_Addr pc, Dwarf_CFI *cfi, Dwarf_Addr bias) continue; } } - else if (! expr_eval (state, frame, reg_ops, reg_nops, ®val, bias)) + else if (! expr_eval (state, reg_ops, reg_nops, ®val, bias, elfclass)) { /* PPC32 vDSO has various invalid operations, ignore them. The register will look as unset causing an error later, if used. diff --git a/libdwfl/libdwflP.h b/libdwfl/libdwflP.h index 63615a8a..5f6bbcdd 100644 --- a/libdwfl/libdwflP.h +++ b/libdwfl/libdwflP.h @@ -1,5 +1,5 @@ /* Internal definitions for libdwfl. - Copyright (C) 2005-2013 Red Hat, Inc. + Copyright (C) 2005-2014 Red Hat, Inc. This file is part of elfutils. This file is free software; you can redistribute it and/or modify @@ -89,7 +89,8 @@ typedef struct Dwfl_Process Dwfl_Process; DWFL_ERROR (ATTACH_STATE_CONFLICT, N_("Dwfl already has attached state")) \ DWFL_ERROR (NO_ATTACH_STATE, N_("Dwfl has no attached state")) \ DWFL_ERROR (NO_UNWIND, N_("Unwinding not supported for this architecture")) \ - DWFL_ERROR (INVALID_ARGUMENT, N_("Invalid argument")) + DWFL_ERROR (INVALID_ARGUMENT, N_("Invalid argument")) \ + DWFL_ERROR (UNWIND_BAD_CFA, N_("Unwind not monotonous (corrupt stack?)")) #define DWFL_ERROR(name, text) DWFL_E_##name, typedef enum { DWFL_ERRORS DWFL_E_NUM } Dwfl_Error; @@ -241,6 +242,8 @@ struct Dwfl_Frame Dwfl_Frame *unwound; bool signal_frame : 1; bool initial_frame : 1; + /* Used to catch infinite unwinding. */ + Dwarf_Addr cfa; enum { /* This structure is still being initialized or there was an error |