From: Andreas Larsson Date: Thu, 4 Feb 2021 16:23:41 +0000 (+0100) Subject: sparc32: Preserve clone syscall flags argument for restarts due to signals X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=c599a7821be7952033727a30e93bd2d053073c78;p=linux.git sparc32: Preserve clone syscall flags argument for restarts due to signals This fixes a bug where a clone syscall that is restarted due to a pending signal is restarted with garbage in the register %o0 that holds the clone flags. This keep the original %i0 of a syscall (as seen from the trap handler) in %l6 rather than %l5. This is done because for clone (and also qfork) %l5 is used as a temporary variable in the same register window. Before this, that temporary value would be the value that was then incorrectly used as the orig_i0 argument to do_notify_resume. In order to preserve %l6, the temporary usage of %l6 in ret_sys_call is changed to use %l5 instead and the setting %l6 to 0 or 1 was removed. The use of that 0 or 1 value in %l6 was removed in commit 28e6103665301ce60634e8a77f0b657c6cc099de. Signed-off-by: Andreas Larsson Signed-off-by: David S. Miller --- diff --git a/arch/sparc/kernel/entry.S b/arch/sparc/kernel/entry.S index f636acf3312f6..c385c93b39bc1 100644 --- a/arch/sparc/kernel/entry.S +++ b/arch/sparc/kernel/entry.S @@ -1009,7 +1009,7 @@ do_syscall: andcc %l5, _TIF_SYSCALL_TRACE, %g0 mov %i4, %o4 bne linux_syscall_trace - mov %i0, %l5 + mov %i0, %l6 2: call %l7 mov %i5, %o5 @@ -1018,16 +1018,15 @@ do_syscall: st %o0, [%sp + STACKFRAME_SZ + PT_I0] ret_sys_call: - ld [%curptr + TI_FLAGS], %l6 + ld [%curptr + TI_FLAGS], %l5 cmp %o0, -ERESTART_RESTARTBLOCK ld [%sp + STACKFRAME_SZ + PT_PSR], %g3 set PSR_C, %g2 bgeu 1f - andcc %l6, _TIF_SYSCALL_TRACE, %g0 + andcc %l5, _TIF_SYSCALL_TRACE, %g0 /* System call success, clear Carry condition code. */ andn %g3, %g2, %g3 - clr %l6 st %g3, [%sp + STACKFRAME_SZ + PT_PSR] bne linux_syscall_trace2 ld [%sp + STACKFRAME_SZ + PT_NPC], %l1 /* pc = npc */ @@ -1042,7 +1041,6 @@ ret_sys_call: sub %g0, %o0, %o0 or %g3, %g2, %g3 st %o0, [%sp + STACKFRAME_SZ + PT_I0] - mov 1, %l6 st %g3, [%sp + STACKFRAME_SZ + PT_PSR] bne linux_syscall_trace2 ld [%sp + STACKFRAME_SZ + PT_NPC], %l1 /* pc = npc */ diff --git a/arch/sparc/kernel/rtrap_32.S b/arch/sparc/kernel/rtrap_32.S index dca8ed8100466..8931fe266346a 100644 --- a/arch/sparc/kernel/rtrap_32.S +++ b/arch/sparc/kernel/rtrap_32.S @@ -75,7 +75,7 @@ signal_p: ld [%sp + STACKFRAME_SZ + PT_PSR], %t_psr mov %g2, %o2 - mov %l5, %o1 + mov %l6, %o1 call do_notify_resume add %sp, STACKFRAME_SZ, %o0 ! pt_regs ptr