Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'x86_urgent_for_v6.2_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Borislav Petkov:
- Two fixes to correct how kprobes handles INT3 now that they're added
by other functionality like the rethunks and not only kgdb
- Remove __init section markings of two functions which are referenced
by a function in the .text section
* tag 'x86_urgent_for_v6.2_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/kprobes: Fix optprobe optimization check with CONFIG_RETHUNK
x86/kprobes: Fix kprobes instruction boudary check with CONFIG_RETHUNK
x86/calldepth: Fix incorrect init section references
+17
-25
+2
-2
arch/x86/kernel/callthunks.c
+2
-2
arch/x86/kernel/callthunks.c
···
119
119
return within_module_coretext(addr);
120
120
}
121
121
122
-
static __init_or_module bool skip_addr(void *dest)
122
+
static bool skip_addr(void *dest)
123
123
{
124
124
if (dest == error_entry)
125
125
return true;
···
181
181
0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
182
182
};
183
183
184
-
static __init_or_module void *patch_dest(void *dest, bool direct)
184
+
static void *patch_dest(void *dest, bool direct)
185
185
{
186
186
unsigned int tsize = SKL_TMPL_SIZE;
187
187
u8 *pad = dest - tsize;
+7
-3
arch/x86/kernel/kprobes/core.c
+7
-3
arch/x86/kernel/kprobes/core.c
···
37
37
#include <linux/extable.h>
38
38
#include <linux/kdebug.h>
39
39
#include <linux/kallsyms.h>
40
+
#include <linux/kgdb.h>
40
41
#include <linux/ftrace.h>
41
42
#include <linux/kasan.h>
42
43
#include <linux/moduleloader.h>
···
282
281
if (ret < 0)
283
282
return 0;
284
283
284
+
#ifdef CONFIG_KGDB
285
285
/*
286
-
* Another debugging subsystem might insert this breakpoint.
287
-
* In that case, we can't recover it.
286
+
* If there is a dynamically installed kgdb sw breakpoint,
287
+
* this function should not be probed.
288
288
*/
289
-
if (insn.opcode.bytes[0] == INT3_INSN_OPCODE)
289
+
if (insn.opcode.bytes[0] == INT3_INSN_OPCODE &&
290
+
kgdb_has_hit_break(addr))
290
291
return 0;
292
+
#endif
291
293
addr += insn.length;
292
294
}
293
295
+8
-20
arch/x86/kernel/kprobes/opt.c
+8
-20
arch/x86/kernel/kprobes/opt.c
···
15
15
#include <linux/extable.h>
16
16
#include <linux/kdebug.h>
17
17
#include <linux/kallsyms.h>
18
+
#include <linux/kgdb.h>
18
19
#include <linux/ftrace.h>
19
20
#include <linux/objtool.h>
20
21
#include <linux/pgtable.h>
···
280
279
return ret;
281
280
}
282
281
283
-
static bool is_padding_int3(unsigned long addr, unsigned long eaddr)
284
-
{
285
-
unsigned char ops;
286
-
287
-
for (; addr < eaddr; addr++) {
288
-
if (get_kernel_nofault(ops, (void *)addr) < 0 ||
289
-
ops != INT3_INSN_OPCODE)
290
-
return false;
291
-
}
292
-
293
-
return true;
294
-
}
295
-
296
282
/* Decode whole function to ensure any instructions don't jump into target */
297
283
static int can_optimize(unsigned long paddr)
298
284
{
···
322
334
ret = insn_decode_kernel(&insn, (void *)recovered_insn);
323
335
if (ret < 0)
324
336
return 0;
325
-
337
+
#ifdef CONFIG_KGDB
326
338
/*
327
-
* In the case of detecting unknown breakpoint, this could be
328
-
* a padding INT3 between functions. Let's check that all the
329
-
* rest of the bytes are also INT3.
339
+
* If there is a dynamically installed kgdb sw breakpoint,
340
+
* this function should not be probed.
330
341
*/
331
-
if (insn.opcode.bytes[0] == INT3_INSN_OPCODE)
332
-
return is_padding_int3(addr, paddr - offset + size) ? 1 : 0;
333
-
342
+
if (insn.opcode.bytes[0] == INT3_INSN_OPCODE &&
343
+
kgdb_has_hit_break(addr))
344
+
return 0;
345
+
#endif
334
346
/* Recover address */
335
347
insn.kaddr = (void *)addr;
336
348
insn.next_byte = (void *)(addr + insn.length);