Author: mjg Date: Thu Dec 13 20:09:38 2018 New Revision: 342053 URL: https://svnweb.freebsd.org/changeset/base/342053
Log: dtrace: fix userspace access on boxes with SMAP dtrace has its own routines which were not updated after SMAP support got implemented. Use ifunc just like for other routines. This in particular fixes ustack(). Reviewed by: markj Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D18542 Modified: head/sys/cddl/dev/dtrace/amd64/dtrace_asm.S head/sys/cddl/dev/dtrace/amd64/dtrace_isa.c Modified: head/sys/cddl/dev/dtrace/amd64/dtrace_asm.S ============================================================================== --- head/sys/cddl/dev/dtrace/amd64/dtrace_asm.S Thu Dec 13 20:00:16 2018 (r342052) +++ head/sys/cddl/dev/dtrace/amd64/dtrace_asm.S Thu Dec 13 20:09:38 2018 (r342053) @@ -208,7 +208,7 @@ dtrace_caller(int aframes) void dtrace_copy(uintptr_t src, uintptr_t dest, size_t size) */ - ENTRY(dtrace_copy) + ENTRY(dtrace_copy_nosmap) pushq %rbp movq %rsp, %rbp @@ -218,14 +218,28 @@ dtrace_copy(uintptr_t src, uintptr_t dest, size_t size smovb /* move from %ds:rsi to %ed:rdi */ leave ret - END(dtrace_copy) + END(dtrace_copy_nosmap) + ENTRY(dtrace_copy_smap) + pushq %rbp + movq %rsp, %rbp + + xchgq %rdi, %rsi /* make %rsi source, %rdi dest */ + movq %rdx, %rcx /* load count */ + stac + repz /* repeat for count ... */ + smovb /* move from %ds:rsi to %ed:rdi */ + clac + leave + ret + END(dtrace_copy_smap) + /* void dtrace_copystr(uintptr_t uaddr, uintptr_t kaddr, size_t size, volatile uint16_t *flags) */ - ENTRY(dtrace_copystr) + ENTRY(dtrace_copystr_nosmap) pushq %rbp movq %rsp, %rbp @@ -248,55 +262,120 @@ dtrace_copystr(uintptr_t uaddr, uintptr_t kaddr, size_ leave ret - END(dtrace_copystr) + END(dtrace_copystr_nosmap) + ENTRY(dtrace_copystr_smap) + pushq %rbp + movq %rsp, %rbp + + stac +0: + movb (%rdi), %al /* load from source */ + movb %al, (%rsi) /* store to destination */ + addq $1, %rdi /* increment source pointer */ + addq $1, %rsi /* increment destination pointer */ + subq $1, %rdx /* decrement remaining count */ + cmpb $0, %al + je 2f + testq $0xfff, %rdx /* test if count is 4k-aligned */ + jnz 1f /* if not, continue with copying */ + testq $CPU_DTRACE_BADADDR, (%rcx) /* load and test dtrace flags */ + jnz 2f +1: + cmpq $0, %rdx + jne 0b +2: + clac + leave + ret + + END(dtrace_copystr_smap) + /* uintptr_t dtrace_fulword(void *addr) */ - ENTRY(dtrace_fulword) + ENTRY(dtrace_fulword_nosmap) movq (%rdi), %rax ret - END(dtrace_fulword) + END(dtrace_fulword_nosmap) + ENTRY(dtrace_fulword_smap) + stac + movq (%rdi), %rax + clac + ret + END(dtrace_fulword_smap) + /* uint8_t dtrace_fuword8_nocheck(void *addr) */ - ENTRY(dtrace_fuword8_nocheck) + ENTRY(dtrace_fuword8_nocheck_nosmap) xorq %rax, %rax movb (%rdi), %al ret - END(dtrace_fuword8_nocheck) + END(dtrace_fuword8_nocheck_nosmap) + ENTRY(dtrace_fuword8_nocheck_smap) + stac + xorq %rax, %rax + movb (%rdi), %al + clac + ret + END(dtrace_fuword8_nocheck_smap) + /* uint16_t dtrace_fuword16_nocheck(void *addr) */ - ENTRY(dtrace_fuword16_nocheck) + ENTRY(dtrace_fuword16_nocheck_nosmap) xorq %rax, %rax movw (%rdi), %ax ret - END(dtrace_fuword16_nocheck) + END(dtrace_fuword16_nocheck_nosmap) + ENTRY(dtrace_fuword16_nocheck_smap) + stac + xorq %rax, %rax + movw (%rdi), %ax + clac + ret + END(dtrace_fuword16_nocheck_smap) + /* uint32_t dtrace_fuword32_nocheck(void *addr) */ - ENTRY(dtrace_fuword32_nocheck) + ENTRY(dtrace_fuword32_nocheck_nosmap) xorq %rax, %rax movl (%rdi), %eax ret - END(dtrace_fuword32_nocheck) + END(dtrace_fuword32_nocheck_nosmap) + ENTRY(dtrace_fuword32_nocheck_smap) + stac + xorq %rax, %rax + movl (%rdi), %eax + clac + ret + END(dtrace_fuword32_nocheck_smap) + /* uint64_t dtrace_fuword64_nocheck(void *addr) */ - ENTRY(dtrace_fuword64_nocheck) + ENTRY(dtrace_fuword64_nocheck_nosmap) movq (%rdi), %rax ret - END(dtrace_fuword64_nocheck) + END(dtrace_fuword64_nocheck_nosmap) + + ENTRY(dtrace_fuword64_nocheck_smap) + stac + movq (%rdi), %rax + clac + ret + END(dtrace_fuword64_nocheck_smap) /* void Modified: head/sys/cddl/dev/dtrace/amd64/dtrace_isa.c ============================================================================== --- head/sys/cddl/dev/dtrace/amd64/dtrace_isa.c Thu Dec 13 20:00:16 2018 (r342052) +++ head/sys/cddl/dev/dtrace/amd64/dtrace_isa.c Thu Dec 13 20:09:38 2018 (r342053) @@ -37,6 +37,7 @@ #include <machine/md_var.h> #include <machine/reg.h> #include <machine/stack.h> +#include <x86/ifunc.h> #include <vm/vm.h> #include <vm/vm_param.h> @@ -663,4 +664,71 @@ dtrace_fuword64(void *uaddr) return (0); } return (dtrace_fuword64_nocheck(uaddr)); +} + +/* + * ifunc resolvers for SMAP support + */ +void dtrace_copy_nosmap(uintptr_t, uintptr_t, size_t); +void dtrace_copy_smap(uintptr_t, uintptr_t, size_t); +DEFINE_IFUNC(, void, dtrace_copy, (uintptr_t, uintptr_t, size_t), static) +{ + + return ((cpu_stdext_feature & CPUID_STDEXT_SMAP) != 0 ? + dtrace_copy_smap : dtrace_copy_nosmap); +} + +void dtrace_copystr_nosmap(uintptr_t, uintptr_t, size_t, volatile uint16_t *); +void dtrace_copystr_smap(uintptr_t, uintptr_t, size_t, volatile uint16_t *); +DEFINE_IFUNC(, void, dtrace_copystr, (uintptr_t, uintptr_t, size_t, + volatile uint16_t *), static) +{ + + return ((cpu_stdext_feature & CPUID_STDEXT_SMAP) != 0 ? + dtrace_copystr_smap : dtrace_copystr_nosmap); +} + +uintptr_t dtrace_fulword_nosmap(void *); +uintptr_t dtrace_fulword_smap(void *); +DEFINE_IFUNC(, uintptr_t, dtrace_fulword, (void *), static) +{ + + return ((cpu_stdext_feature & CPUID_STDEXT_SMAP) != 0 ? + dtrace_fulword_smap : dtrace_fulword_nosmap); +} + +uint8_t dtrace_fuword8_nocheck_nosmap(void *); +uint8_t dtrace_fuword8_nocheck_smap(void *); +DEFINE_IFUNC(, uint8_t, dtrace_fuword8_nocheck, (void *), static) +{ + + return ((cpu_stdext_feature & CPUID_STDEXT_SMAP) != 0 ? + dtrace_fuword8_nocheck_smap : dtrace_fuword8_nocheck_nosmap); +} + +uint16_t dtrace_fuword16_nocheck_nosmap(void *); +uint16_t dtrace_fuword16_nocheck_smap(void *); +DEFINE_IFUNC(, uint16_t, dtrace_fuword16_nocheck, (void *), static) +{ + + return ((cpu_stdext_feature & CPUID_STDEXT_SMAP) != 0 ? + dtrace_fuword16_nocheck_smap : dtrace_fuword16_nocheck_nosmap); +} + +uint32_t dtrace_fuword32_nocheck_nosmap(void *); +uint32_t dtrace_fuword32_nocheck_smap(void *); +DEFINE_IFUNC(, uint32_t, dtrace_fuword32_nocheck, (void *), static) +{ + + return ((cpu_stdext_feature & CPUID_STDEXT_SMAP) != 0 ? + dtrace_fuword32_nocheck_smap : dtrace_fuword32_nocheck_nosmap); +} + +uint64_t dtrace_fuword64_nocheck_nosmap(void *); +uint64_t dtrace_fuword64_nocheck_smap(void *); +DEFINE_IFUNC(, uint64_t, dtrace_fuword64_nocheck, (void *), static) +{ + + return ((cpu_stdext_feature & CPUID_STDEXT_SMAP) != 0 ? + dtrace_fuword64_nocheck_smap : dtrace_fuword64_nocheck_nosmap); } _______________________________________________ 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"
