blob: 0ed92d50e996f5935d59b32d7ab15a8e30251e79 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
|
From d93769405996dfc11d216ddbe415946617b5a494 Mon Sep 17 00:00:00 2001
From: Andreas Schwab <schwab@suse.de>
Date: Mon, 20 Jan 2020 17:01:50 +0100
Subject: [PATCH] Fix array overflow in backtrace on PowerPC (bug 25423)
When unwinding through a signal frame the backtrace function on PowerPC
didn't check array bounds when storing the frame address. Fixes commit
d400dcac5e ("PowerPC: fix backtrace to handle signal trampolines").
CVE: CVE-2020-1751
Upstream-Status: Backport [git://sourceware.org/git/glibc.git]
Signed-off-by: Zhixiong Chi <zhixiong.chi@windriver.com>
---
debug/tst-backtrace5.c | 12 ++++++++++++
sysdeps/powerpc/powerpc32/backtrace.c | 2 ++
sysdeps/powerpc/powerpc64/backtrace.c | 2 ++
3 files changed, 16 insertions(+)
diff --git a/debug/tst-backtrace5.c b/debug/tst-backtrace5.c
index e7ce410845..b2f46160e7 100644
--- a/debug/tst-backtrace5.c
+++ b/debug/tst-backtrace5.c
@@ -89,6 +89,18 @@ handle_signal (int signum)
}
/* Symbol names are not available for static functions, so we do not
check do_test. */
+
+ /* Check that backtrace does not return more than what fits in the array
+ (bug 25423). */
+ for (int j = 0; j < NUM_FUNCTIONS; j++)
+ {
+ n = backtrace (addresses, j);
+ if (n > j)
+ {
+ FAIL ();
+ return;
+ }
+ }
}
NO_INLINE int
diff --git a/sysdeps/powerpc/powerpc32/backtrace.c b/sysdeps/powerpc/powerpc32/backtrace.c
index 7c2d4726f8..d1456c8ae4 100644
--- a/sysdeps/powerpc/powerpc32/backtrace.c
+++ b/sysdeps/powerpc/powerpc32/backtrace.c
@@ -114,6 +114,8 @@ __backtrace (void **array, int size)
}
if (gregset)
{
+ if (count + 1 == size)
+ break;
array[++count] = (void*)((*gregset)[PT_NIP]);
current = (void*)((*gregset)[PT_R1]);
}
diff --git a/sysdeps/powerpc/powerpc64/backtrace.c b/sysdeps/powerpc/powerpc64/backtrace.c
index 65c260ab76..8a53a1088f 100644
--- a/sysdeps/powerpc/powerpc64/backtrace.c
+++ b/sysdeps/powerpc/powerpc64/backtrace.c
@@ -87,6 +87,8 @@ __backtrace (void **array, int size)
if (is_sigtramp_address (current->return_address))
{
struct signal_frame_64 *sigframe = (struct signal_frame_64*) current;
+ if (count + 1 == size)
+ break;
array[++count] = (void*) sigframe->uc.uc_mcontext.gp_regs[PT_NIP];
current = (void*) sigframe->uc.uc_mcontext.gp_regs[PT_R1];
}
--
2.23.0
|
