mirror of
https://github.com/Fishwaldo/build.git
synced 2025-03-26 16:51:48 +00:00
434 lines
13 KiB
Diff
434 lines
13 KiB
Diff
diff --git a/Documentation/x86/exception-tables.txt b/Documentation/x86/exception-tables.txt
|
|
index e396bcd8d830..32901aa36f0a 100644
|
|
--- a/Documentation/x86/exception-tables.txt
|
|
+++ b/Documentation/x86/exception-tables.txt
|
|
@@ -290,38 +290,3 @@ Due to the way that the exception table is built and needs to be ordered,
|
|
only use exceptions for code in the .text section. Any other section
|
|
will cause the exception table to not be sorted correctly, and the
|
|
exceptions will fail.
|
|
-
|
|
-Things changed when 64-bit support was added to x86 Linux. Rather than
|
|
-double the size of the exception table by expanding the two entries
|
|
-from 32-bits to 64 bits, a clever trick was used to store addresses
|
|
-as relative offsets from the table itself. The assembly code changed
|
|
-from:
|
|
- .long 1b,3b
|
|
-to:
|
|
- .long (from) - .
|
|
- .long (to) - .
|
|
-
|
|
-and the C-code that uses these values converts back to absolute addresses
|
|
-like this:
|
|
-
|
|
- ex_insn_addr(const struct exception_table_entry *x)
|
|
- {
|
|
- return (unsigned long)&x->insn + x->insn;
|
|
- }
|
|
-
|
|
-In v4.6 the exception table entry was expanded with a new field "handler".
|
|
-This is also 32-bits wide and contains a third relative function
|
|
-pointer which points to one of:
|
|
-
|
|
-1) int ex_handler_default(const struct exception_table_entry *fixup)
|
|
- This is legacy case that just jumps to the fixup code
|
|
-2) int ex_handler_fault(const struct exception_table_entry *fixup)
|
|
- This case provides the fault number of the trap that occurred at
|
|
- entry->insn. It is used to distinguish page faults from machine
|
|
- check.
|
|
-3) int ex_handler_ext(const struct exception_table_entry *fixup)
|
|
- This case is used for uaccess_err ... we need to set a flag
|
|
- in the task structure. Before the handler functions existed this
|
|
- case was handled by adding a large offset to the fixup to tag
|
|
- it as special.
|
|
-More functions can easily be added.
|
|
diff --git a/Makefile b/Makefile
|
|
index 19d7d9f68e35..98239d56924c 100644
|
|
--- a/Makefile
|
|
+++ b/Makefile
|
|
@@ -1,6 +1,6 @@
|
|
VERSION = 4
|
|
PATCHLEVEL = 4
|
|
-SUBLEVEL = 29
|
|
+SUBLEVEL = 30
|
|
EXTRAVERSION =
|
|
NAME = Blurry Fish Butt
|
|
|
|
diff --git a/arch/x86/include/asm/asm.h b/arch/x86/include/asm/asm.h
|
|
index f5063b6659eb..189679aba703 100644
|
|
--- a/arch/x86/include/asm/asm.h
|
|
+++ b/arch/x86/include/asm/asm.h
|
|
@@ -44,22 +44,19 @@
|
|
|
|
/* Exception table entry */
|
|
#ifdef __ASSEMBLY__
|
|
-# define _ASM_EXTABLE_HANDLE(from, to, handler) \
|
|
+# define _ASM_EXTABLE(from,to) \
|
|
.pushsection "__ex_table","a" ; \
|
|
- .balign 4 ; \
|
|
+ .balign 8 ; \
|
|
.long (from) - . ; \
|
|
.long (to) - . ; \
|
|
- .long (handler) - . ; \
|
|
.popsection
|
|
|
|
-# define _ASM_EXTABLE(from, to) \
|
|
- _ASM_EXTABLE_HANDLE(from, to, ex_handler_default)
|
|
-
|
|
-# define _ASM_EXTABLE_FAULT(from, to) \
|
|
- _ASM_EXTABLE_HANDLE(from, to, ex_handler_fault)
|
|
-
|
|
-# define _ASM_EXTABLE_EX(from, to) \
|
|
- _ASM_EXTABLE_HANDLE(from, to, ex_handler_ext)
|
|
+# define _ASM_EXTABLE_EX(from,to) \
|
|
+ .pushsection "__ex_table","a" ; \
|
|
+ .balign 8 ; \
|
|
+ .long (from) - . ; \
|
|
+ .long (to) - . + 0x7ffffff0 ; \
|
|
+ .popsection
|
|
|
|
# define _ASM_NOKPROBE(entry) \
|
|
.pushsection "_kprobe_blacklist","aw" ; \
|
|
@@ -92,24 +89,19 @@
|
|
.endm
|
|
|
|
#else
|
|
-# define _EXPAND_EXTABLE_HANDLE(x) #x
|
|
-# define _ASM_EXTABLE_HANDLE(from, to, handler) \
|
|
+# define _ASM_EXTABLE(from,to) \
|
|
" .pushsection \"__ex_table\",\"a\"\n" \
|
|
- " .balign 4\n" \
|
|
+ " .balign 8\n" \
|
|
" .long (" #from ") - .\n" \
|
|
" .long (" #to ") - .\n" \
|
|
- " .long (" _EXPAND_EXTABLE_HANDLE(handler) ") - .\n" \
|
|
" .popsection\n"
|
|
|
|
-# define _ASM_EXTABLE(from, to) \
|
|
- _ASM_EXTABLE_HANDLE(from, to, ex_handler_default)
|
|
-
|
|
-# define _ASM_EXTABLE_FAULT(from, to) \
|
|
- _ASM_EXTABLE_HANDLE(from, to, ex_handler_fault)
|
|
-
|
|
-# define _ASM_EXTABLE_EX(from, to) \
|
|
- _ASM_EXTABLE_HANDLE(from, to, ex_handler_ext)
|
|
-
|
|
+# define _ASM_EXTABLE_EX(from,to) \
|
|
+ " .pushsection \"__ex_table\",\"a\"\n" \
|
|
+ " .balign 8\n" \
|
|
+ " .long (" #from ") - .\n" \
|
|
+ " .long (" #to ") - . + 0x7ffffff0\n" \
|
|
+ " .popsection\n"
|
|
/* For C file, we already have NOKPROBE_SYMBOL macro */
|
|
#endif
|
|
|
|
diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h
|
|
index 3794c7331cfc..09b1b0ab94b7 100644
|
|
--- a/arch/x86/include/asm/uaccess.h
|
|
+++ b/arch/x86/include/asm/uaccess.h
|
|
@@ -90,11 +90,12 @@ static inline bool __chk_range_not_ok(unsigned long addr, unsigned long size, un
|
|
likely(!__range_not_ok(addr, size, user_addr_max()))
|
|
|
|
/*
|
|
- * The exception table consists of triples of addresses relative to the
|
|
- * exception table entry itself. The first address is of an instruction
|
|
- * that is allowed to fault, the second is the target at which the program
|
|
- * should continue. The third is a handler function to deal with the fault
|
|
- * caused by the instruction in the first field.
|
|
+ * The exception table consists of pairs of addresses relative to the
|
|
+ * exception table enty itself: the first is the address of an
|
|
+ * instruction that is allowed to fault, and the second is the address
|
|
+ * at which the program should continue. No registers are modified,
|
|
+ * so it is entirely up to the continuation code to figure out what to
|
|
+ * do.
|
|
*
|
|
* All the routines below use bits of fixup code that are out of line
|
|
* with the main instruction path. This means when everything is well,
|
|
@@ -103,14 +104,13 @@ static inline bool __chk_range_not_ok(unsigned long addr, unsigned long size, un
|
|
*/
|
|
|
|
struct exception_table_entry {
|
|
- int insn, fixup, handler;
|
|
+ int insn, fixup;
|
|
};
|
|
/* This is not the generic standard exception_table_entry format */
|
|
#define ARCH_HAS_SORT_EXTABLE
|
|
#define ARCH_HAS_SEARCH_EXTABLE
|
|
|
|
-extern int fixup_exception(struct pt_regs *regs, int trapnr);
|
|
-extern bool ex_has_fault_handler(unsigned long ip);
|
|
+extern int fixup_exception(struct pt_regs *regs);
|
|
extern int early_fixup_exception(unsigned long *ip);
|
|
|
|
/*
|
|
@@ -394,11 +394,7 @@ do { \
|
|
#define __get_user_asm_ex(x, addr, itype, rtype, ltype) \
|
|
asm volatile("1: mov"itype" %1,%"rtype"0\n" \
|
|
"2:\n" \
|
|
- ".section .fixup,\"ax\"\n" \
|
|
- "3:xor"itype" %"rtype"0,%"rtype"0\n" \
|
|
- " jmp 2b\n" \
|
|
- ".previous\n" \
|
|
- _ASM_EXTABLE_EX(1b, 3b) \
|
|
+ _ASM_EXTABLE_EX(1b, 2b) \
|
|
: ltype(x) : "m" (__m(addr)))
|
|
|
|
#define __put_user_nocheck(x, ptr, size) \
|
|
diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
|
|
index e1d1f6cbaf11..023c442c33bb 100644
|
|
--- a/arch/x86/kernel/kprobes/core.c
|
|
+++ b/arch/x86/kernel/kprobes/core.c
|
|
@@ -1000,7 +1000,7 @@ int kprobe_fault_handler(struct pt_regs *regs, int trapnr)
|
|
* In case the user-specified fault handler returned
|
|
* zero, try to fix up.
|
|
*/
|
|
- if (fixup_exception(regs, trapnr))
|
|
+ if (fixup_exception(regs))
|
|
return 1;
|
|
|
|
/*
|
|
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
|
|
index 5621f882645e..679302c312f8 100644
|
|
--- a/arch/x86/kernel/traps.c
|
|
+++ b/arch/x86/kernel/traps.c
|
|
@@ -199,7 +199,7 @@ do_trap_no_signal(struct task_struct *tsk, int trapnr, char *str,
|
|
}
|
|
|
|
if (!user_mode(regs)) {
|
|
- if (!fixup_exception(regs, trapnr)) {
|
|
+ if (!fixup_exception(regs)) {
|
|
tsk->thread.error_code = error_code;
|
|
tsk->thread.trap_nr = trapnr;
|
|
die(str, regs, error_code);
|
|
@@ -453,7 +453,7 @@ do_general_protection(struct pt_regs *regs, long error_code)
|
|
|
|
tsk = current;
|
|
if (!user_mode(regs)) {
|
|
- if (fixup_exception(regs, X86_TRAP_GP))
|
|
+ if (fixup_exception(regs))
|
|
return;
|
|
|
|
tsk->thread.error_code = error_code;
|
|
@@ -699,7 +699,7 @@ static void math_error(struct pt_regs *regs, int error_code, int trapnr)
|
|
conditional_sti(regs);
|
|
|
|
if (!user_mode(regs)) {
|
|
- if (!fixup_exception(regs, trapnr)) {
|
|
+ if (!fixup_exception(regs)) {
|
|
task->thread.error_code = error_code;
|
|
task->thread.trap_nr = trapnr;
|
|
die(str, regs, error_code);
|
|
diff --git a/arch/x86/mm/extable.c b/arch/x86/mm/extable.c
|
|
index 9dd7e4b7fcde..903ec1e9c326 100644
|
|
--- a/arch/x86/mm/extable.c
|
|
+++ b/arch/x86/mm/extable.c
|
|
@@ -3,9 +3,6 @@
|
|
#include <linux/sort.h>
|
|
#include <asm/uaccess.h>
|
|
|
|
-typedef bool (*ex_handler_t)(const struct exception_table_entry *,
|
|
- struct pt_regs *, int);
|
|
-
|
|
static inline unsigned long
|
|
ex_insn_addr(const struct exception_table_entry *x)
|
|
{
|
|
@@ -16,56 +13,11 @@ ex_fixup_addr(const struct exception_table_entry *x)
|
|
{
|
|
return (unsigned long)&x->fixup + x->fixup;
|
|
}
|
|
-static inline ex_handler_t
|
|
-ex_fixup_handler(const struct exception_table_entry *x)
|
|
-{
|
|
- return (ex_handler_t)((unsigned long)&x->handler + x->handler);
|
|
-}
|
|
-
|
|
-bool ex_handler_default(const struct exception_table_entry *fixup,
|
|
- struct pt_regs *regs, int trapnr)
|
|
-{
|
|
- regs->ip = ex_fixup_addr(fixup);
|
|
- return true;
|
|
-}
|
|
-EXPORT_SYMBOL(ex_handler_default);
|
|
-
|
|
-bool ex_handler_fault(const struct exception_table_entry *fixup,
|
|
- struct pt_regs *regs, int trapnr)
|
|
-{
|
|
- regs->ip = ex_fixup_addr(fixup);
|
|
- regs->ax = trapnr;
|
|
- return true;
|
|
-}
|
|
-EXPORT_SYMBOL_GPL(ex_handler_fault);
|
|
-
|
|
-bool ex_handler_ext(const struct exception_table_entry *fixup,
|
|
- struct pt_regs *regs, int trapnr)
|
|
-{
|
|
- /* Special hack for uaccess_err */
|
|
- current_thread_info()->uaccess_err = 1;
|
|
- regs->ip = ex_fixup_addr(fixup);
|
|
- return true;
|
|
-}
|
|
-EXPORT_SYMBOL(ex_handler_ext);
|
|
-
|
|
-bool ex_has_fault_handler(unsigned long ip)
|
|
-{
|
|
- const struct exception_table_entry *e;
|
|
- ex_handler_t handler;
|
|
-
|
|
- e = search_exception_tables(ip);
|
|
- if (!e)
|
|
- return false;
|
|
- handler = ex_fixup_handler(e);
|
|
-
|
|
- return handler == ex_handler_fault;
|
|
-}
|
|
|
|
-int fixup_exception(struct pt_regs *regs, int trapnr)
|
|
+int fixup_exception(struct pt_regs *regs)
|
|
{
|
|
- const struct exception_table_entry *e;
|
|
- ex_handler_t handler;
|
|
+ const struct exception_table_entry *fixup;
|
|
+ unsigned long new_ip;
|
|
|
|
#ifdef CONFIG_PNPBIOS
|
|
if (unlikely(SEGMENT_IS_PNP_CODE(regs->cs))) {
|
|
@@ -81,34 +33,42 @@ int fixup_exception(struct pt_regs *regs, int trapnr)
|
|
}
|
|
#endif
|
|
|
|
- e = search_exception_tables(regs->ip);
|
|
- if (!e)
|
|
- return 0;
|
|
+ fixup = search_exception_tables(regs->ip);
|
|
+ if (fixup) {
|
|
+ new_ip = ex_fixup_addr(fixup);
|
|
+
|
|
+ if (fixup->fixup - fixup->insn >= 0x7ffffff0 - 4) {
|
|
+ /* Special hack for uaccess_err */
|
|
+ current_thread_info()->uaccess_err = 1;
|
|
+ new_ip -= 0x7ffffff0;
|
|
+ }
|
|
+ regs->ip = new_ip;
|
|
+ return 1;
|
|
+ }
|
|
|
|
- handler = ex_fixup_handler(e);
|
|
- return handler(e, regs, trapnr);
|
|
+ return 0;
|
|
}
|
|
|
|
/* Restricted version used during very early boot */
|
|
int __init early_fixup_exception(unsigned long *ip)
|
|
{
|
|
- const struct exception_table_entry *e;
|
|
+ const struct exception_table_entry *fixup;
|
|
unsigned long new_ip;
|
|
- ex_handler_t handler;
|
|
|
|
- e = search_exception_tables(*ip);
|
|
- if (!e)
|
|
- return 0;
|
|
+ fixup = search_exception_tables(*ip);
|
|
+ if (fixup) {
|
|
+ new_ip = ex_fixup_addr(fixup);
|
|
|
|
- new_ip = ex_fixup_addr(e);
|
|
- handler = ex_fixup_handler(e);
|
|
+ if (fixup->fixup - fixup->insn >= 0x7ffffff0 - 4) {
|
|
+ /* uaccess handling not supported during early boot */
|
|
+ return 0;
|
|
+ }
|
|
|
|
- /* special handling not supported during early boot */
|
|
- if (handler != ex_handler_default)
|
|
- return 0;
|
|
+ *ip = new_ip;
|
|
+ return 1;
|
|
+ }
|
|
|
|
- *ip = new_ip;
|
|
- return 1;
|
|
+ return 0;
|
|
}
|
|
|
|
/*
|
|
@@ -173,8 +133,6 @@ void sort_extable(struct exception_table_entry *start,
|
|
i += 4;
|
|
p->fixup += i;
|
|
i += 4;
|
|
- p->handler += i;
|
|
- i += 4;
|
|
}
|
|
|
|
sort(start, finish - start, sizeof(struct exception_table_entry),
|
|
@@ -187,8 +145,6 @@ void sort_extable(struct exception_table_entry *start,
|
|
i += 4;
|
|
p->fixup -= i;
|
|
i += 4;
|
|
- p->handler -= i;
|
|
- i += 4;
|
|
}
|
|
}
|
|
|
|
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
|
|
index 03898aea6e0f..e830c71a1323 100644
|
|
--- a/arch/x86/mm/fault.c
|
|
+++ b/arch/x86/mm/fault.c
|
|
@@ -663,7 +663,7 @@ no_context(struct pt_regs *regs, unsigned long error_code,
|
|
int sig;
|
|
|
|
/* Are we prepared to handle this kernel fault? */
|
|
- if (fixup_exception(regs, X86_TRAP_PF)) {
|
|
+ if (fixup_exception(regs)) {
|
|
/*
|
|
* Any interrupt that takes a fault gets the fixup. This makes
|
|
* the below recursive fault logic only apply to a faults from
|
|
diff --git a/scripts/sortextable.c b/scripts/sortextable.c
|
|
index 7b29fb14f870..c2423d913b46 100644
|
|
--- a/scripts/sortextable.c
|
|
+++ b/scripts/sortextable.c
|
|
@@ -209,35 +209,6 @@ static int compare_relative_table(const void *a, const void *b)
|
|
return 0;
|
|
}
|
|
|
|
-static void x86_sort_relative_table(char *extab_image, int image_size)
|
|
-{
|
|
- int i;
|
|
-
|
|
- i = 0;
|
|
- while (i < image_size) {
|
|
- uint32_t *loc = (uint32_t *)(extab_image + i);
|
|
-
|
|
- w(r(loc) + i, loc);
|
|
- w(r(loc + 1) + i + 4, loc + 1);
|
|
- w(r(loc + 2) + i + 8, loc + 2);
|
|
-
|
|
- i += sizeof(uint32_t) * 3;
|
|
- }
|
|
-
|
|
- qsort(extab_image, image_size / 12, 12, compare_relative_table);
|
|
-
|
|
- i = 0;
|
|
- while (i < image_size) {
|
|
- uint32_t *loc = (uint32_t *)(extab_image + i);
|
|
-
|
|
- w(r(loc) - i, loc);
|
|
- w(r(loc + 1) - (i + 4), loc + 1);
|
|
- w(r(loc + 2) - (i + 8), loc + 2);
|
|
-
|
|
- i += sizeof(uint32_t) * 3;
|
|
- }
|
|
-}
|
|
-
|
|
static void sort_relative_table(char *extab_image, int image_size)
|
|
{
|
|
int i;
|
|
@@ -310,9 +281,6 @@ do_file(char const *const fname)
|
|
break;
|
|
case EM_386:
|
|
case EM_X86_64:
|
|
- custom_sort = x86_sort_relative_table;
|
|
- break;
|
|
-
|
|
case EM_S390:
|
|
custom_sort = sort_relative_table;
|
|
break;
|