From: huangshaobo <[email protected]>
arm32 uses software to simulate the instruction replaced
by kprobe. some instructions may be simulated by constructing
assembly functions. therefore, before executing instruction
simulation, it is necessary to construct assembly function
execution environment in C language through binding registers.
after kasan is enabled, the register binding relationship will
be destroyed, resulting in instruction simulation errors and
causing kernel panic.
the kprobe emulate instruction function is distributed in three
files: actions-common.c actions-arm.c actions-thumb.c, so disable
KASAN when compiling these files.
for example, use kprobe insert on cap_capable+20 after kasan
enabled, the cap_capable assembly code is as follows:
<cap_capable>:
e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr}
e1a05000 mov r5, r0
e280006c add r0, r0, #108 ; 0x6c
e1a04001 mov r4, r1
e1a06002 mov r6, r2
e59fa090 ldr sl, [pc, #144] ;
ebfc7bf8 bl c03aa4b4 <__asan_load4>
e595706c ldr r7, [r5, #108] ; 0x6c
e2859014 add r9, r5, #20
......
The emulate_ldr assembly code after enabling kasan is as follows:
c06f1384 <emulate_ldr>:
e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr}
e282803c add r8, r2, #60 ; 0x3c
e1a05000 mov r5, r0
e7e37855 ubfx r7, r5, #16, #4
e1a00008 mov r0, r8
e1a09001 mov r9, r1
e1a04002 mov r4, r2
ebf35462 bl c03c6530 <__asan_load4>
e357000f cmp r7, #15
e7e36655 ubfx r6, r5, #12, #4
e205a00f and sl, r5, #15
0a000001 beq c06f13bc <emulate_ldr+0x38>
e0840107 add r0, r4, r7, lsl #2
ebf3545c bl c03c6530 <__asan_load4>
e084010a add r0, r4, sl, lsl #2
ebf3545a bl c03c6530 <__asan_load4>
e2890010 add r0, r9, #16
ebf35458 bl c03c6530 <__asan_load4>
e5990010 ldr r0, [r9, #16]
e12fff30 blx r0
e356000f cm r6, #15
1a000014 bne c06f1430 <emulate_ldr+0xac>
e1a06000 mov r6, r0
e2840040 add r0, r4, #64 ; 0x40
......
when running in emulate_ldr to simulate the ldr instruction, panic
occurred, and the log is as follows:
Unable to handle kernel NULL pointer dereference at virtual address
00000090
pgd = ecb46400
[00000090] *pgd=2e0fa003, *pmd=00000000
Internal error: Oops: 206 [#1] SMP ARM
PC is at cap_capable+0x14/0xb0
LR is at emulate_ldr+0x50/0xc0
psr: 600d0293 sp : ecd63af8 ip : 00000004 fp : c0a7c30c
r10: 00000000 r9 : c30897f4 r8 : ecd63cd4
r7 : 0000000f r6 : 0000000a r5 : e59fa090 r4 : ecd63c98
r3 : c06ae294 r2 : 00000000 r1 : b7611300 r0 : bf4ec008
Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment user
Control: 32c5387d Table: 2d546400 DAC: 55555555
Process bash (pid: 1643, stack limit = 0xecd60190)
(cap_capable) from (kprobe_handler+0x218/0x340)
(kprobe_handler) from (kprobe_trap_handler+0x24/0x48)
(kprobe_trap_handler) from (do_undefinstr+0x13c/0x364)
(do_undefinstr) from (__und_svc_finish+0x0/0x30)
(__und_svc_finish) from (cap_capable+0x18/0xb0)
(cap_capable) from (cap_vm_enough_memory+0x38/0x48)
(cap_vm_enough_memory) from
(security_vm_enough_memory_mm+0x48/0x6c)
(security_vm_enough_memory_mm) from
(copy_process.constprop.5+0x16b4/0x25c8)
(copy_process.constprop.5) from (_do_fork+0xe8/0x55c)
(_do_fork) from (SyS_clone+0x1c/0x24)
(SyS_clone) from (__sys_trace_return+0x0/0x10)
Code: 0050a0e1 6c0080e2 0140a0e1 0260a0e1 (f801f0e7)
Fixes: 35aa1df43283 ("ARM kprobes: instruction single-stepping support")
Fixes: 421015713b30 ("ARM: 9017/2: Enable KASan for ARM")
Signed-off-by: huangshaobo <[email protected]>
---
arch/arm/probes/kprobes/Makefile | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/arm/probes/kprobes/Makefile b/arch/arm/probes/kprobes/Makefile
index 14db56f49f0a..6159010dac4a 100644
--- a/arch/arm/probes/kprobes/Makefile
+++ b/arch/arm/probes/kprobes/Makefile
@@ -1,4 +1,7 @@
# SPDX-License-Identifier: GPL-2.0
+KASAN_SANITIZE_actions-common.o := n
+KASAN_SANITIZE_actions-arm.o := n
+KASAN_SANITIZE_actions-thumb.o := n
obj-$(CONFIG_KPROBES) += core.o actions-common.o checkers-common.o
obj-$(CONFIG_ARM_KPROBES_TEST) += test-kprobes.o
test-kprobes-objs := test-core.o
--
2.12.3
On Tue, 9 Feb 2021 at 09:55, Shaobo Huang <[email protected]> wrote:
>
> From: huangshaobo <[email protected]>
>
> arm32 uses software to simulate the instruction replaced
> by kprobe. some instructions may be simulated by constructing
> assembly functions. therefore, before executing instruction
> simulation, it is necessary to construct assembly function
> execution environment in C language through binding registers.
> after kasan is enabled, the register binding relationship will
> be destroyed, resulting in instruction simulation errors and
> causing kernel panic.
>
> the kprobe emulate instruction function is distributed in three
> files: actions-common.c actions-arm.c actions-thumb.c, so disable
> KASAN when compiling these files.
>
> for example, use kprobe insert on cap_capable+20 after kasan
> enabled, the cap_capable assembly code is as follows:
> <cap_capable>:
> e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr}
> e1a05000 mov r5, r0
> e280006c add r0, r0, #108 ; 0x6c
> e1a04001 mov r4, r1
> e1a06002 mov r6, r2
> e59fa090 ldr sl, [pc, #144] ;
> ebfc7bf8 bl c03aa4b4 <__asan_load4>
> e595706c ldr r7, [r5, #108] ; 0x6c
> e2859014 add r9, r5, #20
> ......
> The emulate_ldr assembly code after enabling kasan is as follows:
> c06f1384 <emulate_ldr>:
> e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr}
> e282803c add r8, r2, #60 ; 0x3c
> e1a05000 mov r5, r0
> e7e37855 ubfx r7, r5, #16, #4
> e1a00008 mov r0, r8
> e1a09001 mov r9, r1
> e1a04002 mov r4, r2
> ebf35462 bl c03c6530 <__asan_load4>
> e357000f cmp r7, #15
> e7e36655 ubfx r6, r5, #12, #4
> e205a00f and sl, r5, #15
> 0a000001 beq c06f13bc <emulate_ldr+0x38>
> e0840107 add r0, r4, r7, lsl #2
> ebf3545c bl c03c6530 <__asan_load4>
> e084010a add r0, r4, sl, lsl #2
> ebf3545a bl c03c6530 <__asan_load4>
> e2890010 add r0, r9, #16
> ebf35458 bl c03c6530 <__asan_load4>
> e5990010 ldr r0, [r9, #16]
> e12fff30 blx r0
> e356000f cm r6, #15
> 1a000014 bne c06f1430 <emulate_ldr+0xac>
> e1a06000 mov r6, r0
> e2840040 add r0, r4, #64 ; 0x40
> ......
> when running in emulate_ldr to simulate the ldr instruction, panic
> occurred, and the log is as follows:
> Unable to handle kernel NULL pointer dereference at virtual address
> 00000090
> pgd = ecb46400
> [00000090] *pgd=2e0fa003, *pmd=00000000
> Internal error: Oops: 206 [#1] SMP ARM
> PC is at cap_capable+0x14/0xb0
> LR is at emulate_ldr+0x50/0xc0
> psr: 600d0293 sp : ecd63af8 ip : 00000004 fp : c0a7c30c
> r10: 00000000 r9 : c30897f4 r8 : ecd63cd4
> r7 : 0000000f r6 : 0000000a r5 : e59fa090 r4 : ecd63c98
> r3 : c06ae294 r2 : 00000000 r1 : b7611300 r0 : bf4ec008
> Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment user
> Control: 32c5387d Table: 2d546400 DAC: 55555555
> Process bash (pid: 1643, stack limit = 0xecd60190)
> (cap_capable) from (kprobe_handler+0x218/0x340)
> (kprobe_handler) from (kprobe_trap_handler+0x24/0x48)
> (kprobe_trap_handler) from (do_undefinstr+0x13c/0x364)
> (do_undefinstr) from (__und_svc_finish+0x0/0x30)
> (__und_svc_finish) from (cap_capable+0x18/0xb0)
> (cap_capable) from (cap_vm_enough_memory+0x38/0x48)
> (cap_vm_enough_memory) from
> (security_vm_enough_memory_mm+0x48/0x6c)
> (security_vm_enough_memory_mm) from
> (copy_process.constprop.5+0x16b4/0x25c8)
> (copy_process.constprop.5) from (_do_fork+0xe8/0x55c)
> (_do_fork) from (SyS_clone+0x1c/0x24)
> (SyS_clone) from (__sys_trace_return+0x0/0x10)
> Code: 0050a0e1 6c0080e2 0140a0e1 0260a0e1 (f801f0e7)
>
> Fixes: 35aa1df43283 ("ARM kprobes: instruction single-stepping support")
> Fixes: 421015713b30 ("ARM: 9017/2: Enable KASan for ARM")
> Signed-off-by: huangshaobo <[email protected]>
Acked-by: Ard Biesheuvel <[email protected]>
> ---
> arch/arm/probes/kprobes/Makefile | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/arch/arm/probes/kprobes/Makefile b/arch/arm/probes/kprobes/Makefile
> index 14db56f49f0a..6159010dac4a 100644
> --- a/arch/arm/probes/kprobes/Makefile
> +++ b/arch/arm/probes/kprobes/Makefile
> @@ -1,4 +1,7 @@
> # SPDX-License-Identifier: GPL-2.0
> +KASAN_SANITIZE_actions-common.o := n
> +KASAN_SANITIZE_actions-arm.o := n
> +KASAN_SANITIZE_actions-thumb.o := n
> obj-$(CONFIG_KPROBES) += core.o actions-common.o checkers-common.o
> obj-$(CONFIG_ARM_KPROBES_TEST) += test-kprobes.o
> test-kprobes-objs := test-core.o
> --
> 2.12.3
>
On Thu, 11 Feb 2021 at 09:40, Ard Biesheuvel <[email protected]> wrote:
>
> > From: huangshaobo <[email protected]>
> >
> > arm32 uses software to simulate the instruction replaced
> > by kprobe. some instructions may be simulated by constructing
> > assembly functions. therefore, before executing instruction
> > simulation, it is necessary to construct assembly function
> > execution environment in C language through binding registers.
> > after kasan is enabled, the register binding relationship will
> > be destroyed, resulting in instruction simulation errors and
> > causing kernel panic.
> >
> > the kprobe emulate instruction function is distributed in three
> > files: actions-common.c actions-arm.c actions-thumb.c, so disable
> > KASAN when compiling these files.
> >
> > for example, use kprobe insert on cap_capable+20 after kasan
> > enabled, the cap_capable assembly code is as follows:
> > <cap_capable>:
> > e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr}
> > e1a05000 mov r5, r0
> > e280006c add r0, r0, #108 ; 0x6c
> > e1a04001 mov r4, r1
> > e1a06002 mov r6, r2
> > e59fa090 ldr sl, [pc, #144] ;
> > ebfc7bf8 bl c03aa4b4 <__asan_load4>
> > e595706c ldr r7, [r5, #108] ; 0x6c
> > e2859014 add r9, r5, #20
> > ......
> > The emulate_ldr assembly code after enabling kasan is as follows:
> > c06f1384 <emulate_ldr>:
> > e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr}
> > e282803c add r8, r2, #60 ; 0x3c
> > e1a05000 mov r5, r0
> > e7e37855 ubfx r7, r5, #16, #4
> > e1a00008 mov r0, r8
> > e1a09001 mov r9, r1
> > e1a04002 mov r4, r2
> > ebf35462 bl c03c6530 <__asan_load4>
> > e357000f cmp r7, #15
> > e7e36655 ubfx r6, r5, #12, #4
> > e205a00f and sl, r5, #15
> > 0a000001 beq c06f13bc <emulate_ldr+0x38>
> > e0840107 add r0, r4, r7, lsl #2
> > ebf3545c bl c03c6530 <__asan_load4>
> > e084010a add r0, r4, sl, lsl #2
> > ebf3545a bl c03c6530 <__asan_load4>
> > e2890010 add r0, r9, #16
> > ebf35458 bl c03c6530 <__asan_load4>
> > e5990010 ldr r0, [r9, #16]
> > e12fff30 blx r0
> > e356000f cm r6, #15
> > 1a000014 bne c06f1430 <emulate_ldr+0xac>
> > e1a06000 mov r6, r0
> > e2840040 add r0, r4, #64 ; 0x40
> > ......
> > when running in emulate_ldr to simulate the ldr instruction, panic
> > occurred, and the log is as follows:
> > Unable to handle kernel NULL pointer dereference at virtual address
> > 00000090
> > pgd = ecb46400
> > [00000090] *pgd=2e0fa003, *pmd=00000000
> > Internal error: Oops: 206 [#1] SMP ARM
> > PC is at cap_capable+0x14/0xb0
> > LR is at emulate_ldr+0x50/0xc0
> > psr: 600d0293 sp : ecd63af8 ip : 00000004 fp : c0a7c30c
> > r10: 00000000 r9 : c30897f4 r8 : ecd63cd4
> > r7 : 0000000f r6 : 0000000a r5 : e59fa090 r4 : ecd63c98
> > r3 : c06ae294 r2 : 00000000 r1 : b7611300 r0 : bf4ec008
> > Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment user
> > Control: 32c5387d Table: 2d546400 DAC: 55555555
> > Process bash (pid: 1643, stack limit = 0xecd60190)
> > (cap_capable) from (kprobe_handler+0x218/0x340)
> > (kprobe_handler) from (kprobe_trap_handler+0x24/0x48)
> > (kprobe_trap_handler) from (do_undefinstr+0x13c/0x364)
> > (do_undefinstr) from (__und_svc_finish+0x0/0x30)
> > (__und_svc_finish) from (cap_capable+0x18/0xb0)
> > (cap_capable) from (cap_vm_enough_memory+0x38/0x48)
> > (cap_vm_enough_memory) from
> > (security_vm_enough_memory_mm+0x48/0x6c)
> > (security_vm_enough_memory_mm) from
> > (copy_process.constprop.5+0x16b4/0x25c8)
> > (copy_process.constprop.5) from (_do_fork+0xe8/0x55c)
> > (_do_fork) from (SyS_clone+0x1c/0x24)
> > (SyS_clone) from (__sys_trace_return+0x0/0x10)
> > Code: 0050a0e1 6c0080e2 0140a0e1 0260a0e1 (f801f0e7)
> >
> > Fixes: 35aa1df43283 ("ARM kprobes: instruction single-stepping support")
> > Fixes: 421015713b30 ("ARM: 9017/2: Enable KASan for ARM")
> > Signed-off-by: huangshaobo <[email protected]>
> Acked-by: Ard Biesheuvel <[email protected]>
Maintainer ping?
thanks,
ShaoBo Huang
From: huangshaobo <[email protected]>
arm32 uses software to simulate the instruction replaced
by kprobe. some instructions may be simulated by constructing
assembly functions. therefore, before executing instruction
simulation, it is necessary to construct assembly function
execution environment in C language through binding registers.
after kasan is enabled, the register binding relationship will
be destroyed, resulting in instruction simulation errors and
causing kernel panic.
the kprobe emulate instruction function is distributed in three
files: actions-common.c actions-arm.c actions-thumb.c, so disable
KASAN when compiling these files.
for example, use kprobe insert on cap_capable+20 after kasan
enabled, the cap_capable assembly code is as follows:
<cap_capable>:
e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr}
e1a05000 mov r5, r0
e280006c add r0, r0, #108 ; 0x6c
e1a04001 mov r4, r1
e1a06002 mov r6, r2
e59fa090 ldr sl, [pc, #144] ;
ebfc7bf8 bl c03aa4b4 <__asan_load4>
e595706c ldr r7, [r5, #108] ; 0x6c
e2859014 add r9, r5, #20
......
The emulate_ldr assembly code after enabling kasan is as follows:
c06f1384 <emulate_ldr>:
e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr}
e282803c add r8, r2, #60 ; 0x3c
e1a05000 mov r5, r0
e7e37855 ubfx r7, r5, #16, #4
e1a00008 mov r0, r8
e1a09001 mov r9, r1
e1a04002 mov r4, r2
ebf35462 bl c03c6530 <__asan_load4>
e357000f cmp r7, #15
e7e36655 ubfx r6, r5, #12, #4
e205a00f and sl, r5, #15
0a000001 beq c06f13bc <emulate_ldr+0x38>
e0840107 add r0, r4, r7, lsl #2
ebf3545c bl c03c6530 <__asan_load4>
e084010a add r0, r4, sl, lsl #2
ebf3545a bl c03c6530 <__asan_load4>
e2890010 add r0, r9, #16
ebf35458 bl c03c6530 <__asan_load4>
e5990010 ldr r0, [r9, #16]
e12fff30 blx r0
e356000f cm r6, #15
1a000014 bne c06f1430 <emulate_ldr+0xac>
e1a06000 mov r6, r0
e2840040 add r0, r4, #64 ; 0x40
......
when running in emulate_ldr to simulate the ldr instruction, panic
occurred, and the log is as follows:
Unable to handle kernel NULL pointer dereference at virtual address
00000090
pgd = ecb46400
[00000090] *pgd=2e0fa003, *pmd=00000000
Internal error: Oops: 206 [#1] SMP ARM
PC is at cap_capable+0x14/0xb0
LR is at emulate_ldr+0x50/0xc0
psr: 600d0293 sp : ecd63af8 ip : 00000004 fp : c0a7c30c
r10: 00000000 r9 : c30897f4 r8 : ecd63cd4
r7 : 0000000f r6 : 0000000a r5 : e59fa090 r4 : ecd63c98
r3 : c06ae294 r2 : 00000000 r1 : b7611300 r0 : bf4ec008
Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment user
Control: 32c5387d Table: 2d546400 DAC: 55555555
Process bash (pid: 1643, stack limit = 0xecd60190)
(cap_capable) from (kprobe_handler+0x218/0x340)
(kprobe_handler) from (kprobe_trap_handler+0x24/0x48)
(kprobe_trap_handler) from (do_undefinstr+0x13c/0x364)
(do_undefinstr) from (__und_svc_finish+0x0/0x30)
(__und_svc_finish) from (cap_capable+0x18/0xb0)
(cap_capable) from (cap_vm_enough_memory+0x38/0x48)
(cap_vm_enough_memory) from
(security_vm_enough_memory_mm+0x48/0x6c)
(security_vm_enough_memory_mm) from
(copy_process.constprop.5+0x16b4/0x25c8)
(copy_process.constprop.5) from (_do_fork+0xe8/0x55c)
(_do_fork) from (SyS_clone+0x1c/0x24)
(SyS_clone) from (__sys_trace_return+0x0/0x10)
Code: 0050a0e1 6c0080e2 0140a0e1 0260a0e1 (f801f0e7)
Fixes: 35aa1df43283 ("ARM kprobes: instruction single-stepping support")
Fixes: 421015713b30 ("ARM: 9017/2: Enable KASan for ARM")
Signed-off-by: huangshaobo <[email protected]>
Asked-by: Ard Biesheuvel <[email protected]>
---
arch/arm/probes/kprobes/Makefile | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/arm/probes/kprobes/Makefile b/arch/arm/probes/kprobes/Makefile
index 14db56f49f0a..6159010dac4a 100644
--- a/arch/arm/probes/kprobes/Makefile
+++ b/arch/arm/probes/kprobes/Makefile
@@ -1,4 +1,7 @@
# SPDX-License-Identifier: GPL-2.0
+KASAN_SANITIZE_actions-common.o := n
+KASAN_SANITIZE_actions-arm.o := n
+KASAN_SANITIZE_actions-thumb.o := n
obj-$(CONFIG_KPROBES) += core.o actions-common.o checkers-common.o
obj-$(CONFIG_ARM_KPROBES_TEST) += test-kprobes.o
test-kprobes-objs := test-core.o
--
2.12.3
On Wed, 14 Jul 2021 at 10:27, Shaobo Huang <[email protected]> wrote:
>
> From: huangshaobo <[email protected]>
>
> arm32 uses software to simulate the instruction replaced
> by kprobe. some instructions may be simulated by constructing
> assembly functions. therefore, before executing instruction
> simulation, it is necessary to construct assembly function
> execution environment in C language through binding registers.
> after kasan is enabled, the register binding relationship will
> be destroyed, resulting in instruction simulation errors and
> causing kernel panic.
>
> the kprobe emulate instruction function is distributed in three
> files: actions-common.c actions-arm.c actions-thumb.c, so disable
> KASAN when compiling these files.
>
> for example, use kprobe insert on cap_capable+20 after kasan
> enabled, the cap_capable assembly code is as follows:
> <cap_capable>:
> e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr}
> e1a05000 mov r5, r0
> e280006c add r0, r0, #108 ; 0x6c
> e1a04001 mov r4, r1
> e1a06002 mov r6, r2
> e59fa090 ldr sl, [pc, #144] ;
> ebfc7bf8 bl c03aa4b4 <__asan_load4>
> e595706c ldr r7, [r5, #108] ; 0x6c
> e2859014 add r9, r5, #20
> ......
> The emulate_ldr assembly code after enabling kasan is as follows:
> c06f1384 <emulate_ldr>:
> e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr}
> e282803c add r8, r2, #60 ; 0x3c
> e1a05000 mov r5, r0
> e7e37855 ubfx r7, r5, #16, #4
> e1a00008 mov r0, r8
> e1a09001 mov r9, r1
> e1a04002 mov r4, r2
> ebf35462 bl c03c6530 <__asan_load4>
> e357000f cmp r7, #15
> e7e36655 ubfx r6, r5, #12, #4
> e205a00f and sl, r5, #15
> 0a000001 beq c06f13bc <emulate_ldr+0x38>
> e0840107 add r0, r4, r7, lsl #2
> ebf3545c bl c03c6530 <__asan_load4>
> e084010a add r0, r4, sl, lsl #2
> ebf3545a bl c03c6530 <__asan_load4>
> e2890010 add r0, r9, #16
> ebf35458 bl c03c6530 <__asan_load4>
> e5990010 ldr r0, [r9, #16]
> e12fff30 blx r0
> e356000f cm r6, #15
> 1a000014 bne c06f1430 <emulate_ldr+0xac>
> e1a06000 mov r6, r0
> e2840040 add r0, r4, #64 ; 0x40
> ......
>
> when running in emulate_ldr to simulate the ldr instruction, panic
> occurred, and the log is as follows:
> Unable to handle kernel NULL pointer dereference at virtual address
> 00000090
> pgd = ecb46400
> [00000090] *pgd=2e0fa003, *pmd=00000000
> Internal error: Oops: 206 [#1] SMP ARM
> PC is at cap_capable+0x14/0xb0
> LR is at emulate_ldr+0x50/0xc0
> psr: 600d0293 sp : ecd63af8 ip : 00000004 fp : c0a7c30c
> r10: 00000000 r9 : c30897f4 r8 : ecd63cd4
> r7 : 0000000f r6 : 0000000a r5 : e59fa090 r4 : ecd63c98
> r3 : c06ae294 r2 : 00000000 r1 : b7611300 r0 : bf4ec008
> Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment user
> Control: 32c5387d Table: 2d546400 DAC: 55555555
> Process bash (pid: 1643, stack limit = 0xecd60190)
> (cap_capable) from (kprobe_handler+0x218/0x340)
> (kprobe_handler) from (kprobe_trap_handler+0x24/0x48)
> (kprobe_trap_handler) from (do_undefinstr+0x13c/0x364)
> (do_undefinstr) from (__und_svc_finish+0x0/0x30)
> (__und_svc_finish) from (cap_capable+0x18/0xb0)
> (cap_capable) from (cap_vm_enough_memory+0x38/0x48)
> (cap_vm_enough_memory) from
> (security_vm_enough_memory_mm+0x48/0x6c)
> (security_vm_enough_memory_mm) from
> (copy_process.constprop.5+0x16b4/0x25c8)
> (copy_process.constprop.5) from (_do_fork+0xe8/0x55c)
> (_do_fork) from (SyS_clone+0x1c/0x24)
> (SyS_clone) from (__sys_trace_return+0x0/0x10)
> Code: 0050a0e1 6c0080e2 0140a0e1 0260a0e1 (f801f0e7)
>
> Fixes: 35aa1df43283 ("ARM kprobes: instruction single-stepping support")
> Fixes: 421015713b30 ("ARM: 9017/2: Enable KASan for ARM")
> Signed-off-by: huangshaobo <[email protected]>
> Asked-by: Ard Biesheuvel <[email protected]>
Please don't do this - the maintainer will pick it up when applying,
or when you send a new version of the patch, it is OK to add these
tags if you have not made any substantial changes.
But please do *not* add tags like this on someone else's behalf by
replying to the email - and I should also point out that 'asked-by' is
bogus.
> ---
> arch/arm/probes/kprobes/Makefile | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/arch/arm/probes/kprobes/Makefile b/arch/arm/probes/kprobes/Makefile
> index 14db56f49f0a..6159010dac4a 100644
> --- a/arch/arm/probes/kprobes/Makefile
> +++ b/arch/arm/probes/kprobes/Makefile
> @@ -1,4 +1,7 @@
> # SPDX-License-Identifier: GPL-2.0
> +KASAN_SANITIZE_actions-common.o := n
> +KASAN_SANITIZE_actions-arm.o := n
> +KASAN_SANITIZE_actions-thumb.o := n
> obj-$(CONFIG_KPROBES) += core.o actions-common.o checkers-common.o
> obj-$(CONFIG_ARM_KPROBES_TEST) += test-kprobes.o
> test-kprobes-objs := test-core.o
> --
> 2.12.3
>
On Sat, 17 Jul 2021 at 01:01, Ard Biesheuvel <[email protected]> wrote:
> On Wed, 14 Jul 2021 at 10:27, Shaobo Huang <[email protected]> wrote:
>>
>> From: huangshaobo <[email protected]>
>>
>> arm32 uses software to simulate the instruction replaced
>> by kprobe. some instructions may be simulated by constructing
>> assembly functions. therefore, before executing instruction
>> simulation, it is necessary to construct assembly function
>> execution environment in C language through binding registers.
>> after kasan is enabled, the register binding relationship will
>> be destroyed, resulting in instruction simulation errors and
>> causing kernel panic.
>>
>> the kprobe emulate instruction function is distributed in three
>> files: actions-common.c actions-arm.c actions-thumb.c, so disable
>> KASAN when compiling these files.
>>
>> for example, use kprobe insert on cap_capable+20 after kasan
>> enabled, the cap_capable assembly code is as follows:
>> <cap_capable>:
>> e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr}
>> e1a05000 mov r5, r0
>> e280006c add r0, r0, #108 ; 0x6c
>> e1a04001 mov r4, r1
>> e1a06002 mov r6, r2
>> e59fa090 ldr sl, [pc, #144] ;
>> ebfc7bf8 bl c03aa4b4 <__asan_load4>
>> e595706c ldr r7, [r5, #108] ; 0x6c
>> e2859014 add r9, r5, #20
>> ......
>> The emulate_ldr assembly code after enabling kasan is as follows:
>> c06f1384 <emulate_ldr>:
>> e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr}
>> e282803c add r8, r2, #60 ; 0x3c
>> e1a05000 mov r5, r0
>> e7e37855 ubfx r7, r5, #16, #4
>> e1a00008 mov r0, r8
>> e1a09001 mov r9, r1
>> e1a04002 mov r4, r2
>> ebf35462 bl c03c6530 <__asan_load4>
>> e357000f cmp r7, #15
>> e7e36655 ubfx r6, r5, #12, #4
>> e205a00f and sl, r5, #15
>> 0a000001 beq c06f13bc <emulate_ldr+0x38>
>> e0840107 add r0, r4, r7, lsl #2
>> ebf3545c bl c03c6530 <__asan_load4>
>> e084010a add r0, r4, sl, lsl #2
>> ebf3545a bl c03c6530 <__asan_load4>
>> e2890010 add r0, r9, #16
>> ebf35458 bl c03c6530 <__asan_load4>
>> e5990010 ldr r0, [r9, #16]
>> e12fff30 blx r0
>> e356000f cm r6, #15
>> 1a000014 bne c06f1430 <emulate_ldr+0xac>
>> e1a06000 mov r6, r0
>> e2840040 add r0, r4, #64 ; 0x40
>> ......
>>
>> when running in emulate_ldr to simulate the ldr instruction, panic
>> occurred, and the log is as follows:
>> Unable to handle kernel NULL pointer dereference at virtual address
>> 00000090
>> pgd = ecb46400
>> [00000090] *pgd=2e0fa003, *pmd=00000000
>> Internal error: Oops: 206 [#1] SMP ARM
>> PC is at cap_capable+0x14/0xb0
>> LR is at emulate_ldr+0x50/0xc0
>> psr: 600d0293 sp : ecd63af8 ip : 00000004 fp : c0a7c30c
>> r10: 00000000 r9 : c30897f4 r8 : ecd63cd4
>> r7 : 0000000f r6 : 0000000a r5 : e59fa090 r4 : ecd63c98
>> r3 : c06ae294 r2 : 00000000 r1 : b7611300 r0 : bf4ec008
>> Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment user
>> Control: 32c5387d Table: 2d546400 DAC: 55555555
>> Process bash (pid: 1643, stack limit = 0xecd60190)
>> (cap_capable) from (kprobe_handler+0x218/0x340)
>> (kprobe_handler) from (kprobe_trap_handler+0x24/0x48)
>> (kprobe_trap_handler) from (do_undefinstr+0x13c/0x364)
>> (do_undefinstr) from (__und_svc_finish+0x0/0x30)
>> (__und_svc_finish) from (cap_capable+0x18/0xb0)
>> (cap_capable) from (cap_vm_enough_memory+0x38/0x48)
>> (cap_vm_enough_memory) from
>> (security_vm_enough_memory_mm+0x48/0x6c)
>> (security_vm_enough_memory_mm) from
>> (copy_process.constprop.5+0x16b4/0x25c8)
>> (copy_process.constprop.5) from (_do_fork+0xe8/0x55c)
>> (_do_fork) from (SyS_clone+0x1c/0x24)
>> (SyS_clone) from (__sys_trace_return+0x0/0x10)
>> Code: 0050a0e1 6c0080e2 0140a0e1 0260a0e1 (f801f0e7)
>>
>> Fixes: 35aa1df43283 ("ARM kprobes: instruction single-stepping support")
>> Fixes: 421015713b30 ("ARM: 9017/2: Enable KASan for ARM")
>> Signed-off-by: huangshaobo <[email protected]>
>> Asked-by: Ard Biesheuvel <[email protected]>
>
> Please don't do this - the maintainer will pick it up when applying,
> or when you send a new version of the patch, it is OK to add these
> tags if you have not made any substantial changes.
>
> But please do *not* add tags like this on someone else's behalf by
> replying to the email - and I should also point out that 'asked-by' is
> bogus.
>
Hi ardb,
1.The original patch you have been asked-by by email before, link: https://lore.kernel.org/linux-arm-kernel/CAMj1kXGqfF68MT4WwrxS0cYiUBb0gODDh-wGZSQcW9vxdfK90A@mail.gmail.com/
2.In addition to adding the asked-by tag, there is no other content modification in this patch
3.The patch was reissued because the previous recipient did not include kasan maintainer and reviewers
thanks,
ShaoBo Huang
>
>> ---
>> arch/arm/probes/kprobes/Makefile | 3 +++
>> 1 file changed, 3 insertions(+)
>>
>> diff --git a/arch/arm/probes/kprobes/Makefile b/arch/arm/probes/kprobes/Makefile
>> index 14db56f49f0a..6159010dac4a 100644
>> --- a/arch/arm/probes/kprobes/Makefile
>> +++ b/arch/arm/probes/kprobes/Makefile
>> @@ -1,4 +1,7 @@
>> # SPDX-License-Identifier: GPL-2.0
>> +KASAN_SANITIZE_actions-common.o := n
>> +KASAN_SANITIZE_actions-arm.o := n
>> +KASAN_SANITIZE_actions-thumb.o := n
>> obj-$(CONFIG_KPROBES) += core.o actions-common.o checkers-common.o
>> obj-$(CONFIG_ARM_KPROBES_TEST) += test-kprobes.o
>> test-kprobes-objs := test-core.o
>> --
>> 2.12.3
>>
On Mon, 19 Jul 2021 at 05:09, Shaobo Huang <[email protected]> wrote:
>
> On Sat, 17 Jul 2021 at 01:01, Ard Biesheuvel <[email protected]> wrote:
> > On Wed, 14 Jul 2021 at 10:27, Shaobo Huang <[email protected]> wrote:
> >>
> >> From: huangshaobo <[email protected]>
> >>
> >> arm32 uses software to simulate the instruction replaced
> >> by kprobe. some instructions may be simulated by constructing
> >> assembly functions. therefore, before executing instruction
> >> simulation, it is necessary to construct assembly function
> >> execution environment in C language through binding registers.
> >> after kasan is enabled, the register binding relationship will
> >> be destroyed, resulting in instruction simulation errors and
> >> causing kernel panic.
> >>
> >> the kprobe emulate instruction function is distributed in three
> >> files: actions-common.c actions-arm.c actions-thumb.c, so disable
> >> KASAN when compiling these files.
> >>
> >> for example, use kprobe insert on cap_capable+20 after kasan
> >> enabled, the cap_capable assembly code is as follows:
> >> <cap_capable>:
> >> e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr}
> >> e1a05000 mov r5, r0
> >> e280006c add r0, r0, #108 ; 0x6c
> >> e1a04001 mov r4, r1
> >> e1a06002 mov r6, r2
> >> e59fa090 ldr sl, [pc, #144] ;
> >> ebfc7bf8 bl c03aa4b4 <__asan_load4>
> >> e595706c ldr r7, [r5, #108] ; 0x6c
> >> e2859014 add r9, r5, #20
> >> ......
> >> The emulate_ldr assembly code after enabling kasan is as follows:
> >> c06f1384 <emulate_ldr>:
> >> e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr}
> >> e282803c add r8, r2, #60 ; 0x3c
> >> e1a05000 mov r5, r0
> >> e7e37855 ubfx r7, r5, #16, #4
> >> e1a00008 mov r0, r8
> >> e1a09001 mov r9, r1
> >> e1a04002 mov r4, r2
> >> ebf35462 bl c03c6530 <__asan_load4>
> >> e357000f cmp r7, #15
> >> e7e36655 ubfx r6, r5, #12, #4
> >> e205a00f and sl, r5, #15
> >> 0a000001 beq c06f13bc <emulate_ldr+0x38>
> >> e0840107 add r0, r4, r7, lsl #2
> >> ebf3545c bl c03c6530 <__asan_load4>
> >> e084010a add r0, r4, sl, lsl #2
> >> ebf3545a bl c03c6530 <__asan_load4>
> >> e2890010 add r0, r9, #16
> >> ebf35458 bl c03c6530 <__asan_load4>
> >> e5990010 ldr r0, [r9, #16]
> >> e12fff30 blx r0
> >> e356000f cm r6, #15
> >> 1a000014 bne c06f1430 <emulate_ldr+0xac>
> >> e1a06000 mov r6, r0
> >> e2840040 add r0, r4, #64 ; 0x40
> >> ......
> >>
> >> when running in emulate_ldr to simulate the ldr instruction, panic
> >> occurred, and the log is as follows:
> >> Unable to handle kernel NULL pointer dereference at virtual address
> >> 00000090
> >> pgd = ecb46400
> >> [00000090] *pgd=2e0fa003, *pmd=00000000
> >> Internal error: Oops: 206 [#1] SMP ARM
> >> PC is at cap_capable+0x14/0xb0
> >> LR is at emulate_ldr+0x50/0xc0
> >> psr: 600d0293 sp : ecd63af8 ip : 00000004 fp : c0a7c30c
> >> r10: 00000000 r9 : c30897f4 r8 : ecd63cd4
> >> r7 : 0000000f r6 : 0000000a r5 : e59fa090 r4 : ecd63c98
> >> r3 : c06ae294 r2 : 00000000 r1 : b7611300 r0 : bf4ec008
> >> Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment user
> >> Control: 32c5387d Table: 2d546400 DAC: 55555555
> >> Process bash (pid: 1643, stack limit = 0xecd60190)
> >> (cap_capable) from (kprobe_handler+0x218/0x340)
> >> (kprobe_handler) from (kprobe_trap_handler+0x24/0x48)
> >> (kprobe_trap_handler) from (do_undefinstr+0x13c/0x364)
> >> (do_undefinstr) from (__und_svc_finish+0x0/0x30)
> >> (__und_svc_finish) from (cap_capable+0x18/0xb0)
> >> (cap_capable) from (cap_vm_enough_memory+0x38/0x48)
> >> (cap_vm_enough_memory) from
> >> (security_vm_enough_memory_mm+0x48/0x6c)
> >> (security_vm_enough_memory_mm) from
> >> (copy_process.constprop.5+0x16b4/0x25c8)
> >> (copy_process.constprop.5) from (_do_fork+0xe8/0x55c)
> >> (_do_fork) from (SyS_clone+0x1c/0x24)
> >> (SyS_clone) from (__sys_trace_return+0x0/0x10)
> >> Code: 0050a0e1 6c0080e2 0140a0e1 0260a0e1 (f801f0e7)
> >>
> >> Fixes: 35aa1df43283 ("ARM kprobes: instruction single-stepping support")
> >> Fixes: 421015713b30 ("ARM: 9017/2: Enable KASan for ARM")
> >> Signed-off-by: huangshaobo <[email protected]>
> >> Asked-by: Ard Biesheuvel <[email protected]>
> >
> > Please don't do this - the maintainer will pick it up when applying,
> > or when you send a new version of the patch, it is OK to add these
> > tags if you have not made any substantial changes.
> >
> > But please do *not* add tags like this on someone else's behalf by
> > replying to the email - and I should also point out that 'asked-by' is
> > bogus.
> >
>
> Hi ardb,
> 1.The original patch you have been asked-by by email before, link: https://lore.kernel.org/linux-arm-kernel/CAMj1kXGqfF68MT4WwrxS0cYiUBb0gODDh-wGZSQcW9vxdfK90A@mail.gmail.com/
No it was not.
It was ACKed by, not ASKed by.
> 2.In addition to adding the asked-by tag, there is no other content modification in this patch
> 3.The patch was reissued because the previous recipient did not include kasan maintainer and reviewers
>
I don't care. Do NOT reply to emails with tags in other people's names.
> thanks,
> ShaoBo Huang
>
> >
> >> ---
> >> arch/arm/probes/kprobes/Makefile | 3 +++
> >> 1 file changed, 3 insertions(+)
> >>
> >> diff --git a/arch/arm/probes/kprobes/Makefile b/arch/arm/probes/kprobes/Makefile
> >> index 14db56f49f0a..6159010dac4a 100644
> >> --- a/arch/arm/probes/kprobes/Makefile
> >> +++ b/arch/arm/probes/kprobes/Makefile
> >> @@ -1,4 +1,7 @@
> >> # SPDX-License-Identifier: GPL-2.0
> >> +KASAN_SANITIZE_actions-common.o := n
> >> +KASAN_SANITIZE_actions-arm.o := n
> >> +KASAN_SANITIZE_actions-thumb.o := n
> >> obj-$(CONFIG_KPROBES) += core.o actions-common.o checkers-common.o
> >> obj-$(CONFIG_ARM_KPROBES_TEST) += test-kprobes.o
> >> test-kprobes-objs := test-core.o
> >> --
> >> 2.12.3
> >>
On Mon, 19 Jul 2021 at 07:06, Ard Biesheuvel <[email protected]> wrote:
> On Mon, 19 Jul 2021 at 05:09, Shaobo Huang <[email protected]> wrote:
> >
> > On Sat, 17 Jul 2021 at 01:01, Ard Biesheuvel <[email protected]> wrote:
> > > On Wed, 14 Jul 2021 at 10:27, Shaobo Huang <[email protected]> wrote:
> > >>
> > >> From: huangshaobo <[email protected]>
> > >>
> > >> arm32 uses software to simulate the instruction replaced
> > >> by kprobe. some instructions may be simulated by constructing
> > >> assembly functions. therefore, before executing instruction
> > >> simulation, it is necessary to construct assembly function
> > >> execution environment in C language through binding registers.
> > >> after kasan is enabled, the register binding relationship will
> > >> be destroyed, resulting in instruction simulation errors and
> > >> causing kernel panic.
> > >>
> > >> the kprobe emulate instruction function is distributed in three
> > >> files: actions-common.c actions-arm.c actions-thumb.c, so disable
> > >> KASAN when compiling these files.
> > >>
> > >> for example, use kprobe insert on cap_capable+20 after kasan
> > >> enabled, the cap_capable assembly code is as follows:
> > >> <cap_capable>:
> > >> e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr}
> > >> e1a05000 mov r5, r0
> > >> e280006c add r0, r0, #108 ; 0x6c
> > >> e1a04001 mov r4, r1
> > >> e1a06002 mov r6, r2
> > >> e59fa090 ldr sl, [pc, #144] ;
> > >> ebfc7bf8 bl c03aa4b4 <__asan_load4>
> > >> e595706c ldr r7, [r5, #108] ; 0x6c
> > >> e2859014 add r9, r5, #20
> > >> ......
> > >> The emulate_ldr assembly code after enabling kasan is as follows:
> > >> c06f1384 <emulate_ldr>:
> > >> e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr}
> > >> e282803c add r8, r2, #60 ; 0x3c
> > >> e1a05000 mov r5, r0
> > >> e7e37855 ubfx r7, r5, #16, #4
> > >> e1a00008 mov r0, r8
> > >> e1a09001 mov r9, r1
> > >> e1a04002 mov r4, r2
> > >> ebf35462 bl c03c6530 <__asan_load4>
> > >> e357000f cmp r7, #15
> > >> e7e36655 ubfx r6, r5, #12, #4
> > >> e205a00f and sl, r5, #15
> > >> 0a000001 beq c06f13bc <emulate_ldr+0x38>
> > >> e0840107 add r0, r4, r7, lsl #2
> > >> ebf3545c bl c03c6530 <__asan_load4>
> > >> e084010a add r0, r4, sl, lsl #2
> > >> ebf3545a bl c03c6530 <__asan_load4>
> > >> e2890010 add r0, r9, #16
> > >> ebf35458 bl c03c6530 <__asan_load4>
> > >> e5990010 ldr r0, [r9, #16]
> > >> e12fff30 blx r0
> > >> e356000f cm r6, #15
> > >> 1a000014 bne c06f1430 <emulate_ldr+0xac>
> > >> e1a06000 mov r6, r0
> > >> e2840040 add r0, r4, #64 ; 0x40
> > >> ......
> > >>
> > >> when running in emulate_ldr to simulate the ldr instruction, panic
> > >> occurred, and the log is as follows:
> > >> Unable to handle kernel NULL pointer dereference at virtual address
> > >> 00000090
> > >> pgd = ecb46400
> > >> [00000090] *pgd=2e0fa003, *pmd=00000000
> > >> Internal error: Oops: 206 [#1] SMP ARM
> > >> PC is at cap_capable+0x14/0xb0
> > >> LR is at emulate_ldr+0x50/0xc0
> > >> psr: 600d0293 sp : ecd63af8 ip : 00000004 fp : c0a7c30c
> > >> r10: 00000000 r9 : c30897f4 r8 : ecd63cd4
> > >> r7 : 0000000f r6 : 0000000a r5 : e59fa090 r4 : ecd63c98
> > >> r3 : c06ae294 r2 : 00000000 r1 : b7611300 r0 : bf4ec008
> > >> Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment user
> > >> Control: 32c5387d Table: 2d546400 DAC: 55555555
> > >> Process bash (pid: 1643, stack limit = 0xecd60190)
> > >> (cap_capable) from (kprobe_handler+0x218/0x340)
> > >> (kprobe_handler) from (kprobe_trap_handler+0x24/0x48)
> > >> (kprobe_trap_handler) from (do_undefinstr+0x13c/0x364)
> > >> (do_undefinstr) from (__und_svc_finish+0x0/0x30)
> > >> (__und_svc_finish) from (cap_capable+0x18/0xb0)
> > >> (cap_capable) from (cap_vm_enough_memory+0x38/0x48)
> > >> (cap_vm_enough_memory) from
> > >> (security_vm_enough_memory_mm+0x48/0x6c)
> > >> (security_vm_enough_memory_mm) from
> > >> (copy_process.constprop.5+0x16b4/0x25c8)
> > >> (copy_process.constprop.5) from (_do_fork+0xe8/0x55c)
> > >> (_do_fork) from (SyS_clone+0x1c/0x24)
> > >> (SyS_clone) from (__sys_trace_return+0x0/0x10)
> > >> Code: 0050a0e1 6c0080e2 0140a0e1 0260a0e1 (f801f0e7)
> > >>
> > >> Fixes: 35aa1df43283 ("ARM kprobes: instruction single-stepping support")
> > >> Fixes: 421015713b30 ("ARM: 9017/2: Enable KASan for ARM")
> > >> Signed-off-by: huangshaobo <[email protected]>
> > >> Asked-by: Ard Biesheuvel <[email protected]>
> > >
> > > Please don't do this - the maintainer will pick it up when applying,
> > > or when you send a new version of the patch, it is OK to add these
> > > tags if you have not made any substantial changes.
> > >
> > > But please do *not* add tags like this on someone else's behalf by
> > > replying to the email - and I should also point out that 'asked-by' is
> > > bogus.
> > >
> >
> > Hi ardb,
> > 1.The original patch you have been asked-by by email before, link: https://lore.kernel.org/linux-arm-kernel/CAMj1kXGqfF68MT4WwrxS0cYiUBb0gODDh-wGZSQcW9vxdfK90A@mail.gmail.com/
>
> No it was not.
>
> It was ACKed by, not ASKed by.
>
> > 2.In addition to adding the asked-by tag, there is no other content modification in this patch
> > 3.The patch was reissued because the previous recipient did not include kasan maintainer and reviewers
> >
>
> I don't care. Do NOT reply to emails with tags in other people's names.
>
Hi ardb,
Sincerely apologize for my mistake,
I mistakenly wrote the Acked-by label as Asked-by.
Do I need to change to Acked-by or remove the label and reissue a patch?
thanks,
Shaobo Huang
>
> > thanks,
> > ShaoBo Huang
> >
> > >
> > >> ---
> > >> arch/arm/probes/kprobes/Makefile | 3 +++
> > >> 1 file changed, 3 insertions(+)
> > >>
> > >> diff --git a/arch/arm/probes/kprobes/Makefile b/arch/arm/probes/kprobes/Makefile
> > >> index 14db56f49f0a..6159010dac4a 100644
> > >> --- a/arch/arm/probes/kprobes/Makefile
> > >> +++ b/arch/arm/probes/kprobes/Makefile
> > >> @@ -1,4 +1,7 @@
> > >> # SPDX-License-Identifier: GPL-2.0
> > >> +KASAN_SANITIZE_actions-common.o := n
> > >> +KASAN_SANITIZE_actions-arm.o := n
> > >> +KASAN_SANITIZE_actions-thumb.o := n
> > >> obj-$(CONFIG_KPROBES) += core.o actions-common.o checkers-common.o
> > >> obj-$(CONFIG_ARM_KPROBES_TEST) += test-kprobes.o
> > >> test-kprobes-objs := test-core.o
> > >> --
> > >> 2.12.3
> > >>
On Mon, 19 Jul 2021 at 09:45, Shaobo Huang <[email protected]> wrote:
>
> On Mon, 19 Jul 2021 at 07:06, Ard Biesheuvel <[email protected]> wrote:
> > On Mon, 19 Jul 2021 at 05:09, Shaobo Huang <[email protected]> wrote:
> > >
> > > On Sat, 17 Jul 2021 at 01:01, Ard Biesheuvel <[email protected]> wrote:
> > > > On Wed, 14 Jul 2021 at 10:27, Shaobo Huang <[email protected]> wrote:
> > > >>
> > > >> From: huangshaobo <[email protected]>
> > > >>
> > > >> arm32 uses software to simulate the instruction replaced
> > > >> by kprobe. some instructions may be simulated by constructing
> > > >> assembly functions. therefore, before executing instruction
> > > >> simulation, it is necessary to construct assembly function
> > > >> execution environment in C language through binding registers.
> > > >> after kasan is enabled, the register binding relationship will
> > > >> be destroyed, resulting in instruction simulation errors and
> > > >> causing kernel panic.
> > > >>
> > > >> the kprobe emulate instruction function is distributed in three
> > > >> files: actions-common.c actions-arm.c actions-thumb.c, so disable
> > > >> KASAN when compiling these files.
> > > >>
> > > >> for example, use kprobe insert on cap_capable+20 after kasan
> > > >> enabled, the cap_capable assembly code is as follows:
> > > >> <cap_capable>:
> > > >> e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr}
> > > >> e1a05000 mov r5, r0
> > > >> e280006c add r0, r0, #108 ; 0x6c
> > > >> e1a04001 mov r4, r1
> > > >> e1a06002 mov r6, r2
> > > >> e59fa090 ldr sl, [pc, #144] ;
> > > >> ebfc7bf8 bl c03aa4b4 <__asan_load4>
> > > >> e595706c ldr r7, [r5, #108] ; 0x6c
> > > >> e2859014 add r9, r5, #20
> > > >> ......
> > > >> The emulate_ldr assembly code after enabling kasan is as follows:
> > > >> c06f1384 <emulate_ldr>:
> > > >> e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr}
> > > >> e282803c add r8, r2, #60 ; 0x3c
> > > >> e1a05000 mov r5, r0
> > > >> e7e37855 ubfx r7, r5, #16, #4
> > > >> e1a00008 mov r0, r8
> > > >> e1a09001 mov r9, r1
> > > >> e1a04002 mov r4, r2
> > > >> ebf35462 bl c03c6530 <__asan_load4>
> > > >> e357000f cmp r7, #15
> > > >> e7e36655 ubfx r6, r5, #12, #4
> > > >> e205a00f and sl, r5, #15
> > > >> 0a000001 beq c06f13bc <emulate_ldr+0x38>
> > > >> e0840107 add r0, r4, r7, lsl #2
> > > >> ebf3545c bl c03c6530 <__asan_load4>
> > > >> e084010a add r0, r4, sl, lsl #2
> > > >> ebf3545a bl c03c6530 <__asan_load4>
> > > >> e2890010 add r0, r9, #16
> > > >> ebf35458 bl c03c6530 <__asan_load4>
> > > >> e5990010 ldr r0, [r9, #16]
> > > >> e12fff30 blx r0
> > > >> e356000f cm r6, #15
> > > >> 1a000014 bne c06f1430 <emulate_ldr+0xac>
> > > >> e1a06000 mov r6, r0
> > > >> e2840040 add r0, r4, #64 ; 0x40
> > > >> ......
> > > >>
> > > >> when running in emulate_ldr to simulate the ldr instruction, panic
> > > >> occurred, and the log is as follows:
> > > >> Unable to handle kernel NULL pointer dereference at virtual address
> > > >> 00000090
> > > >> pgd = ecb46400
> > > >> [00000090] *pgd=2e0fa003, *pmd=00000000
> > > >> Internal error: Oops: 206 [#1] SMP ARM
> > > >> PC is at cap_capable+0x14/0xb0
> > > >> LR is at emulate_ldr+0x50/0xc0
> > > >> psr: 600d0293 sp : ecd63af8 ip : 00000004 fp : c0a7c30c
> > > >> r10: 00000000 r9 : c30897f4 r8 : ecd63cd4
> > > >> r7 : 0000000f r6 : 0000000a r5 : e59fa090 r4 : ecd63c98
> > > >> r3 : c06ae294 r2 : 00000000 r1 : b7611300 r0 : bf4ec008
> > > >> Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment user
> > > >> Control: 32c5387d Table: 2d546400 DAC: 55555555
> > > >> Process bash (pid: 1643, stack limit = 0xecd60190)
> > > >> (cap_capable) from (kprobe_handler+0x218/0x340)
> > > >> (kprobe_handler) from (kprobe_trap_handler+0x24/0x48)
> > > >> (kprobe_trap_handler) from (do_undefinstr+0x13c/0x364)
> > > >> (do_undefinstr) from (__und_svc_finish+0x0/0x30)
> > > >> (__und_svc_finish) from (cap_capable+0x18/0xb0)
> > > >> (cap_capable) from (cap_vm_enough_memory+0x38/0x48)
> > > >> (cap_vm_enough_memory) from
> > > >> (security_vm_enough_memory_mm+0x48/0x6c)
> > > >> (security_vm_enough_memory_mm) from
> > > >> (copy_process.constprop.5+0x16b4/0x25c8)
> > > >> (copy_process.constprop.5) from (_do_fork+0xe8/0x55c)
> > > >> (_do_fork) from (SyS_clone+0x1c/0x24)
> > > >> (SyS_clone) from (__sys_trace_return+0x0/0x10)
> > > >> Code: 0050a0e1 6c0080e2 0140a0e1 0260a0e1 (f801f0e7)
> > > >>
> > > >> Fixes: 35aa1df43283 ("ARM kprobes: instruction single-stepping support")
> > > >> Fixes: 421015713b30 ("ARM: 9017/2: Enable KASan for ARM")
> > > >> Signed-off-by: huangshaobo <[email protected]>
> > > >> Asked-by: Ard Biesheuvel <[email protected]>
> > > >
> > > > Please don't do this - the maintainer will pick it up when applying,
> > > > or when you send a new version of the patch, it is OK to add these
> > > > tags if you have not made any substantial changes.
> > > >
> > > > But please do *not* add tags like this on someone else's behalf by
> > > > replying to the email - and I should also point out that 'asked-by' is
> > > > bogus.
> > > >
> > >
> > > Hi ardb,
> > > 1.The original patch you have been asked-by by email before, link: https://lore.kernel.org/linux-arm-kernel/CAMj1kXGqfF68MT4WwrxS0cYiUBb0gODDh-wGZSQcW9vxdfK90A@mail.gmail.com/
> >
> > No it was not.
> >
> > It was ACKed by, not ASKed by.
> >
> > > 2.In addition to adding the asked-by tag, there is no other content modification in this patch
> > > 3.The patch was reissued because the previous recipient did not include kasan maintainer and reviewers
> > >
> >
> > I don't care. Do NOT reply to emails with tags in other people's names.
> >
> Hi ardb,
> Sincerely apologize for my mistake,
> I mistakenly wrote the Acked-by label as Asked-by.
> Do I need to change to Acked-by or remove the label and reissue a patch?
>
You can put this patch into rmk's patch tracker at armlinux.org.uk. In
this case, it is ok to include the tags that were given in reply, ie.,
my acked-by
--
Ard.
> >
> > > thanks,
> > > ShaoBo Huang
> > >
> > > >
> > > >> ---
> > > >> arch/arm/probes/kprobes/Makefile | 3 +++
> > > >> 1 file changed, 3 insertions(+)
> > > >>
> > > >> diff --git a/arch/arm/probes/kprobes/Makefile b/arch/arm/probes/kprobes/Makefile
> > > >> index 14db56f49f0a..6159010dac4a 100644
> > > >> --- a/arch/arm/probes/kprobes/Makefile
> > > >> +++ b/arch/arm/probes/kprobes/Makefile
> > > >> @@ -1,4 +1,7 @@
> > > >> # SPDX-License-Identifier: GPL-2.0
> > > >> +KASAN_SANITIZE_actions-common.o := n
> > > >> +KASAN_SANITIZE_actions-arm.o := n
> > > >> +KASAN_SANITIZE_actions-thumb.o := n
> > > >> obj-$(CONFIG_KPROBES) += core.o actions-common.o checkers-common.o
> > > >> obj-$(CONFIG_ARM_KPROBES_TEST) += test-kprobes.o
> > > >> test-kprobes-objs := test-core.o
> > > >> --
> > > >> 2.12.3
> > > >>