diff options
| author | Maciej W. Rozycki <macro@imgtec.com> | 2017-06-16 00:14:12 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-07-27 15:08:05 -0700 |
| commit | 3330a05c5c6ebb6134479bca4758d9766d1c9663 (patch) | |
| tree | 17b77a0ddece9a9bd64d0e00ce0ee9313da62577 | |
| parent | d4bd6a1df2c816b7027f9cf1a900ae52f528f300 (diff) | |
MIPS: Send SIGILL for R6 branches in `__compute_return_epc_for_insn'
commit a60b1a5bf88a250f1a77977c0224e502c901c77b upstream.
Fix:
* commit 8467ca0122e2 ("MIPS: Emulate the new MIPS R6 branch compact
(BC) instruction"),
* commit 84fef630127a ("MIPS: Emulate the new MIPS R6 BALC
instruction"),
* commit 69b9a2fd05a3 ("MIPS: Emulate the new MIPS R6 BEQZC and JIC
instructions"),
* commit 28d6f93d201d ("MIPS: Emulate the new MIPS R6 BNEZC and JIALC
instructions"),
* commit c893ce38b265 ("MIPS: Emulate the new MIPS R6 BOVC, BEQC and
BEQZALC instructions")
and send SIGILL rather than returning -SIGILL for R6 branch and jump
instructions. Returning -SIGILL is never correct as the API defines
this function's result upon error to be -EFAULT and a signal actually
issued.
Fixes: 8467ca0122e2 ("MIPS: Emulate the new MIPS R6 branch compact (BC) instruction")
Fixes: 84fef630127a ("MIPS: Emulate the new MIPS R6 BALC instruction")
Fixes: 69b9a2fd05a3 ("MIPS: Emulate the new MIPS R6 BEQZC and JIC instructions")
Fixes: 28d6f93d201d ("MIPS: Emulate the new MIPS R6 BNEZC and JIALC instructions")
Fixes: c893ce38b265 ("MIPS: Emulate the new MIPS R6 BOVC, BEQC and BEQZALC instructions")
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16399/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/mips/kernel/branch.c | 35 |
1 files changed, 15 insertions, 20 deletions
diff --git a/arch/mips/kernel/branch.c b/arch/mips/kernel/branch.c index ddf0f0270b1c..be6d4ba989bd 100644 --- a/arch/mips/kernel/branch.c +++ b/arch/mips/kernel/branch.c @@ -771,35 +771,27 @@ int __compute_return_epc_for_insn(struct pt_regs *regs, #else case bc6_op: /* Only valid for MIPS R6 */ - if (!cpu_has_mips_r6) { - ret = -SIGILL; - break; - } + if (!cpu_has_mips_r6) + goto sigill_r6; regs->cp0_epc += 8; break; case balc6_op: - if (!cpu_has_mips_r6) { - ret = -SIGILL; - break; - } + if (!cpu_has_mips_r6) + goto sigill_r6; /* Compact branch: BALC */ regs->regs[31] = epc + 4; epc += 4 + (insn.i_format.simmediate << 2); regs->cp0_epc = epc; break; case pop66_op: - if (!cpu_has_mips_r6) { - ret = -SIGILL; - break; - } + if (!cpu_has_mips_r6) + goto sigill_r6; /* Compact branch: BEQZC || JIC */ regs->cp0_epc += 8; break; case pop76_op: - if (!cpu_has_mips_r6) { - ret = -SIGILL; - break; - } + if (!cpu_has_mips_r6) + goto sigill_r6; /* Compact branch: BNEZC || JIALC */ if (!insn.i_format.rs) { /* JIALC: set $31/ra */ @@ -811,10 +803,8 @@ int __compute_return_epc_for_insn(struct pt_regs *regs, case pop10_op: case pop30_op: /* Only valid for MIPS R6 */ - if (!cpu_has_mips_r6) { - ret = -SIGILL; - break; - } + if (!cpu_has_mips_r6) + goto sigill_r6; /* * Compact branches: * bovc, beqc, beqzalc, bnvc, bnec, bnezlac @@ -837,6 +827,11 @@ sigill_r2r6: current->comm); force_sig(SIGILL, current); return -EFAULT; +sigill_r6: + pr_info("%s: R6 branch but no MIPSr6 ISA support - sending SIGILL.\n", + current->comm); + force_sig(SIGILL, current); + return -EFAULT; } EXPORT_SYMBOL_GPL(__compute_return_epc_for_insn); |