diff options
Diffstat (limited to 'arch/sparc/kernel/etrap_64.S')
| -rw-r--r-- | arch/sparc/kernel/etrap_64.S | 54 |
1 files changed, 49 insertions, 5 deletions
diff --git a/arch/sparc/kernel/etrap_64.S b/arch/sparc/kernel/etrap_64.S index 1276ca2567ba..08cc41f64725 100644 --- a/arch/sparc/kernel/etrap_64.S +++ b/arch/sparc/kernel/etrap_64.S @@ -1,3 +1,4 @@ +/* SPDX-License-Identifier: GPL-2.0 */ /* * etrap.S: Preparing for entry into the kernel on Sparc V9. * @@ -38,7 +39,11 @@ etrap_syscall: TRAP_LOAD_THREAD_REG(%g6, %g1) or %g1, %g3, %g1 bne,pn %xcc, 1f sub %sp, STACKFRAME_SZ+TRACEREG_SZ-STACK_BIAS, %g2 - wrpr %g0, 7, %cleanwin +661: wrpr %g0, 7, %cleanwin + .section .fast_win_ctrl_1insn_patch, "ax" + .word 661b + .word 0x85880000 ! allclean + .previous sethi %hi(TASK_REGOFF), %g2 sethi %hi(TSTATE_PEF), %g3 @@ -88,16 +93,30 @@ etrap_save: save %g2, -STACK_BIAS, %sp bne,pn %xcc, 3f mov PRIMARY_CONTEXT, %l4 - rdpr %canrestore, %g3 +661: rdpr %canrestore, %g3 + .section .fast_win_ctrl_1insn_patch, "ax" + .word 661b + nop + .previous + rdpr %wstate, %g2 - wrpr %g0, 0, %canrestore +661: wrpr %g0, 0, %canrestore + .section .fast_win_ctrl_1insn_patch, "ax" + .word 661b + nop + .previous sll %g2, 3, %g2 /* Set TI_SYS_FPDEPTH to 1 and clear TI_SYS_NOERROR. */ mov 1, %l5 sth %l5, [%l6 + TI_SYS_NOERROR] - wrpr %g3, 0, %otherwin +661: wrpr %g3, 0, %otherwin + .section .fast_win_ctrl_1insn_patch, "ax" + .word 661b + .word 0x87880000 ! otherw + .previous + wrpr %g2, 0, %wstate sethi %hi(sparc64_kern_pri_context), %g2 ldx [%g2 + %lo(sparc64_kern_pri_context)], %g3 @@ -132,7 +151,32 @@ etrap_save: save %g2, -STACK_BIAS, %sp stx %g6, [%sp + PTREGS_OFF + PT_V9_G6] stx %g7, [%sp + PTREGS_OFF + PT_V9_G7] or %l7, %l0, %l7 - sethi %hi(TSTATE_TSO | TSTATE_PEF), %l0 +661: sethi %hi(TSTATE_TSO | TSTATE_PEF), %l0 + /* If userspace is using ADI, it could potentially pass + * a pointer with version tag embedded in it. To maintain + * the ADI security, we must enable PSTATE.mcde. Userspace + * would have already set TTE.mcd in an earlier call to + * kernel and set the version tag for the address being + * dereferenced. Setting PSTATE.mcde would ensure any + * access to userspace data through a system call honors + * ADI and does not allow a rogue app to bypass ADI by + * using system calls. Setting PSTATE.mcde only affects + * accesses to virtual addresses that have TTE.mcd set. + * Set PMCDPER to ensure any exceptions caused by ADI + * version tag mismatch are exposed before system call + * returns to userspace. Setting PMCDPER affects only + * writes to virtual addresses that have TTE.mcd set and + * have a version tag set as well. + */ + .section .sun_m7_1insn_patch, "ax" + .word 661b + sethi %hi(TSTATE_TSO | TSTATE_PEF | TSTATE_MCDE), %l0 + .previous +661: nop + .section .sun_m7_1insn_patch, "ax" + .word 661b + .word 0xaf902001 /* wrpr %g0, 1, %pmcdper */ + .previous or %l7, %l0, %l7 wrpr %l2, %tnpc wrpr %l7, (TSTATE_PRIV | TSTATE_IE), %tstate |