diff options
| author | Masami Hiramatsu <mhiramat@kernel.org> | 2018-05-13 07:04:29 +0300 |
|---|---|---|
| committer | Russell King <rmk+kernel@armlinux.org.uk> | 2018-05-19 13:35:56 +0300 |
| commit | 0d73c3f8e7f6ee2aab1bb350f60c180f5ae21a2c (patch) | |
| tree | 1157529f1984e2f576326efb9fcc5dda67a9da86 | |
| parent | eb0146daefdde65665b7f076fbff7b49dade95b9 (diff) | |
| download | linux-0d73c3f8e7f6ee2aab1bb350f60c180f5ae21a2c.tar.xz | |
ARM: 8772/1: kprobes: Prohibit kprobes on get_user functions
Since do_undefinstr() uses get_user to get the undefined
instruction, it can be called before kprobes processes
recursive check. This can cause an infinit recursive
exception.
Prohibit probing on get_user functions.
Fixes: 24ba613c9d6c ("ARM kprobes: core code")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
| -rw-r--r-- | arch/arm/include/asm/assembler.h | 10 | ||||
| -rw-r--r-- | arch/arm/lib/getuser.S | 10 |
2 files changed, 20 insertions, 0 deletions
diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h index bc8d4bbd82e2..9342904cccca 100644 --- a/arch/arm/include/asm/assembler.h +++ b/arch/arm/include/asm/assembler.h @@ -536,4 +536,14 @@ THUMB( orr \reg , \reg , #PSR_T_BIT ) #endif .endm +#ifdef CONFIG_KPROBES +#define _ASM_NOKPROBE(entry) \ + .pushsection "_kprobe_blacklist", "aw" ; \ + .balign 4 ; \ + .long entry; \ + .popsection +#else +#define _ASM_NOKPROBE(entry) +#endif + #endif /* __ASM_ASSEMBLER_H__ */ diff --git a/arch/arm/lib/getuser.S b/arch/arm/lib/getuser.S index df73914e81c8..746e7801dcdf 100644 --- a/arch/arm/lib/getuser.S +++ b/arch/arm/lib/getuser.S @@ -38,6 +38,7 @@ ENTRY(__get_user_1) mov r0, #0 ret lr ENDPROC(__get_user_1) +_ASM_NOKPROBE(__get_user_1) ENTRY(__get_user_2) check_uaccess r0, 2, r1, r2, __get_user_bad @@ -58,6 +59,7 @@ rb .req r0 mov r0, #0 ret lr ENDPROC(__get_user_2) +_ASM_NOKPROBE(__get_user_2) ENTRY(__get_user_4) check_uaccess r0, 4, r1, r2, __get_user_bad @@ -65,6 +67,7 @@ ENTRY(__get_user_4) mov r0, #0 ret lr ENDPROC(__get_user_4) +_ASM_NOKPROBE(__get_user_4) ENTRY(__get_user_8) check_uaccess r0, 8, r1, r2, __get_user_bad8 @@ -78,6 +81,7 @@ ENTRY(__get_user_8) mov r0, #0 ret lr ENDPROC(__get_user_8) +_ASM_NOKPROBE(__get_user_8) #ifdef __ARMEB__ ENTRY(__get_user_32t_8) @@ -91,6 +95,7 @@ ENTRY(__get_user_32t_8) mov r0, #0 ret lr ENDPROC(__get_user_32t_8) +_ASM_NOKPROBE(__get_user_32t_8) ENTRY(__get_user_64t_1) check_uaccess r0, 1, r1, r2, __get_user_bad8 @@ -98,6 +103,7 @@ ENTRY(__get_user_64t_1) mov r0, #0 ret lr ENDPROC(__get_user_64t_1) +_ASM_NOKPROBE(__get_user_64t_1) ENTRY(__get_user_64t_2) check_uaccess r0, 2, r1, r2, __get_user_bad8 @@ -114,6 +120,7 @@ rb .req r0 mov r0, #0 ret lr ENDPROC(__get_user_64t_2) +_ASM_NOKPROBE(__get_user_64t_2) ENTRY(__get_user_64t_4) check_uaccess r0, 4, r1, r2, __get_user_bad8 @@ -121,6 +128,7 @@ ENTRY(__get_user_64t_4) mov r0, #0 ret lr ENDPROC(__get_user_64t_4) +_ASM_NOKPROBE(__get_user_64t_4) #endif __get_user_bad8: @@ -131,6 +139,8 @@ __get_user_bad: ret lr ENDPROC(__get_user_bad) ENDPROC(__get_user_bad8) +_ASM_NOKPROBE(__get_user_bad) +_ASM_NOKPROBE(__get_user_bad8) .pushsection __ex_table, "a" .long 1b, __get_user_bad |