Author: kib Date: Mon Jan 1 20:47:03 2018 New Revision: 327472 URL: https://svnweb.freebsd.org/changeset/base/327472
Log: Avoid re-check of usermode condition. It does not change anything in the behavior of trap_pfault(), while eliminating obfuscation of jumping to the code which checks for the condition reversed of the goto cause. Also avoid force initialize the rv variable, since it is now only accessed after storing vm_fault() return value. Reviewed by: alc Sponsored by: The FreeBSD Foundation MFC after: 1 week Differential revision: https://reviews.freebsd.org/D13725 Modified: head/sys/amd64/amd64/trap.c head/sys/i386/i386/trap.c Modified: head/sys/amd64/amd64/trap.c ============================================================================== --- head/sys/amd64/amd64/trap.c Mon Jan 1 20:39:12 2018 (r327471) +++ head/sys/amd64/amd64/trap.c Mon Jan 1 20:47:03 2018 (r327472) @@ -608,7 +608,6 @@ trap_pfault(struct trapframe *frame, int usermode) td = curthread; p = td->td_proc; eva = frame->tf_addr; - rv = 0; if (__predict_false((td->td_pflags & TDP_NOFAULTING) != 0)) { /* @@ -660,7 +659,7 @@ trap_pfault(struct trapframe *frame, int usermode) * Don't allow user-mode faults in kernel address space. */ if (usermode) - goto nogo; + return (SIGSEGV); map = kernel_map; } else { @@ -715,7 +714,6 @@ trap_pfault(struct trapframe *frame, int usermode) #endif return (0); } -nogo: if (!usermode) { if (td->td_intr_nesting_level == 0 && curpcb->pcb_onfault != NULL) { Modified: head/sys/i386/i386/trap.c ============================================================================== --- head/sys/i386/i386/trap.c Mon Jan 1 20:39:12 2018 (r327471) +++ head/sys/i386/i386/trap.c Mon Jan 1 20:47:03 2018 (r327472) @@ -744,7 +744,6 @@ trap_pfault(struct trapframe *frame, int usermode, vm_ td = curthread; p = td->td_proc; - rv = 0; if (__predict_false((td->td_pflags & TDP_NOFAULTING) != 0)) { /* @@ -805,7 +804,7 @@ trap_pfault(struct trapframe *frame, int usermode, vm_ return (-2); #endif if (usermode) - goto nogo; + return (SIGSEGV); map = kernel_map; } else { @@ -862,7 +861,6 @@ trap_pfault(struct trapframe *frame, int usermode, vm_ #endif return (0); } -nogo: if (!usermode) { if (td->td_intr_nesting_level == 0 && curpcb->pcb_onfault != NULL) { _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
