projects / thirdparty / kernel / stable-queue.git / blame
| Commit | Line | Data |
|---|---|---|
| 221ef3ca GKH |
1 | From 0d73c3f8e7f6ee2aab1bb350f60c180f5ae21a2c Mon Sep 17 00:00:00 2001 |
| 2 | From: Masami Hiramatsu <mhiramat@kernel.org> | |
| 3 | Date: Sun, 13 May 2018 05:04:29 +0100 | |
| 4 | Subject: ARM: 8772/1: kprobes: Prohibit kprobes on get_user functions | |
| 5 | ||
| 6 | From: Masami Hiramatsu <mhiramat@kernel.org> | |
| 7 | ||
| 8 | commit 0d73c3f8e7f6ee2aab1bb350f60c180f5ae21a2c upstream. | |
| 9 | ||
| 10 | Since do_undefinstr() uses get_user to get the undefined | |
| 11 | instruction, it can be called before kprobes processes | |
| 12 | recursive check. This can cause an infinit recursive | |
| 13 | exception. | |
| 14 | Prohibit probing on get_user functions. | |
| 15 | ||
| 16 | Fixes: 24ba613c9d6c ("ARM kprobes: core code") | |
| 17 | Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> | |
| 18 | Cc: stable@vger.kernel.org | |
| 19 | Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> | |
| 20 | Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> | |
| 21 | ||
| 22 | --- | |
| 23 | arch/arm/include/asm/assembler.h | 10 ++++++++++ | |
| 24 | arch/arm/lib/getuser.S | 10 ++++++++++ | |
| 25 | 2 files changed, 20 insertions(+) | |
| 26 | ||
| 27 | --- a/arch/arm/include/asm/assembler.h | |
| 28 | +++ b/arch/arm/include/asm/assembler.h | |
| 29 | @@ -530,4 +530,14 @@ THUMB( orr \reg , \reg , #PSR_T_BIT ) | |
| 30 | #endif | |
| 31 | .endm | |
| 32 | ||
| 33 | +#ifdef CONFIG_KPROBES | |
| 34 | +#define _ASM_NOKPROBE(entry) \ | |
| 35 | + .pushsection "_kprobe_blacklist", "aw" ; \ | |
| 36 | + .balign 4 ; \ | |
| 37 | + .long entry; \ | |
| 38 | + .popsection | |
| 39 | +#else | |
| 40 | +#define _ASM_NOKPROBE(entry) | |
| 41 | +#endif | |
| 42 | + | |
| 43 | #endif /* __ASM_ASSEMBLER_H__ */ | |
| 44 | --- a/arch/arm/lib/getuser.S | |
| 45 | +++ b/arch/arm/lib/getuser.S | |
| 46 | @@ -38,6 +38,7 @@ ENTRY(__get_user_1) | |
| 47 | mov r0, #0 | |
| 48 | ret lr | |
| 49 | ENDPROC(__get_user_1) | |
| 50 | +_ASM_NOKPROBE(__get_user_1) | |
| 51 | ||
| 52 | ENTRY(__get_user_2) | |
| 53 | check_uaccess r0, 2, r1, r2, __get_user_bad | |
| 54 | @@ -58,6 +59,7 @@ rb .req r0 | |
| 55 | mov r0, #0 | |
| 56 | ret lr | |
| 57 | ENDPROC(__get_user_2) | |
| 58 | +_ASM_NOKPROBE(__get_user_2) | |
| 59 | ||
| 60 | ENTRY(__get_user_4) | |
| 61 | check_uaccess r0, 4, r1, r2, __get_user_bad | |
| 62 | @@ -65,6 +67,7 @@ ENTRY(__get_user_4) | |
| 63 | mov r0, #0 | |
| 64 | ret lr | |
| 65 | ENDPROC(__get_user_4) | |
| 66 | +_ASM_NOKPROBE(__get_user_4) | |
| 67 | ||
| 68 | ENTRY(__get_user_8) | |
| 69 | check_uaccess r0, 8, r1, r2, __get_user_bad8 | |
| 70 | @@ -78,6 +81,7 @@ ENTRY(__get_user_8) | |
| 71 | mov r0, #0 | |
| 72 | ret lr | |
| 73 | ENDPROC(__get_user_8) | |
| 74 | +_ASM_NOKPROBE(__get_user_8) | |
| 75 | ||
| 76 | #ifdef __ARMEB__ | |
| 77 | ENTRY(__get_user_32t_8) | |
| 78 | @@ -91,6 +95,7 @@ ENTRY(__get_user_32t_8) | |
| 79 | mov r0, #0 | |
| 80 | ret lr | |
| 81 | ENDPROC(__get_user_32t_8) | |
| 82 | +_ASM_NOKPROBE(__get_user_32t_8) | |
| 83 | ||
| 84 | ENTRY(__get_user_64t_1) | |
| 85 | check_uaccess r0, 1, r1, r2, __get_user_bad8 | |
| 86 | @@ -98,6 +103,7 @@ ENTRY(__get_user_64t_1) | |
| 87 | mov r0, #0 | |
| 88 | ret lr | |
| 89 | ENDPROC(__get_user_64t_1) | |
| 90 | +_ASM_NOKPROBE(__get_user_64t_1) | |
| 91 | ||
| 92 | ENTRY(__get_user_64t_2) | |
| 93 | check_uaccess r0, 2, r1, r2, __get_user_bad8 | |
| 94 | @@ -114,6 +120,7 @@ rb .req r0 | |
| 95 | mov r0, #0 | |
| 96 | ret lr | |
| 97 | ENDPROC(__get_user_64t_2) | |
| 98 | +_ASM_NOKPROBE(__get_user_64t_2) | |
| 99 | ||
| 100 | ENTRY(__get_user_64t_4) | |
| 101 | check_uaccess r0, 4, r1, r2, __get_user_bad8 | |
| 102 | @@ -121,6 +128,7 @@ ENTRY(__get_user_64t_4) | |
| 103 | mov r0, #0 | |
| 104 | ret lr | |
| 105 | ENDPROC(__get_user_64t_4) | |
| 106 | +_ASM_NOKPROBE(__get_user_64t_4) | |
| 107 | #endif | |
| 108 | ||
| 109 | __get_user_bad8: | |
| 110 | @@ -131,6 +139,8 @@ __get_user_bad: | |
| 111 | ret lr | |
| 112 | ENDPROC(__get_user_bad) | |
| 113 | ENDPROC(__get_user_bad8) | |
| 114 | +_ASM_NOKPROBE(__get_user_bad) | |
| 115 | +_ASM_NOKPROBE(__get_user_bad8) | |
| 116 | ||
| 117 | .pushsection __ex_table, "a" | |
| 118 | .long 1b, __get_user_bad |