From: He Zhe <[email protected]>
When loading modules with CONFIG_ARCH_HAS_STRICT_MODULE_RWX enabled and
CONFIG_STRICT_MODULE_RWX disabled, the memory allocated for modules would
not be page-aligned and cause the following BUG during frob_text.
------------[ cut here ]------------
kernel BUG at kernel/module.c:1907!
Internal error: Oops - BUG: 0 [#1] ARM
Modules linked in:
CPU: 0 PID: 89 Comm: systemd-modules Not tainted 5.3.0-rc2 #1
Hardware name: ARM-Versatile (Device Tree Support)
PC is at frob_text.constprop.0+0x2c/0x40
LR is at load_module+0x14b4/0x1d28
pc : [<c0082930>] lr : [<c0084bb0>] psr: 20000013
sp : ce44fe58 ip : 00000000 fp : 00000000
r10: 00000000 r9 : ce44feb8 r8 : 00000000
r7 : 00000001 r6 : bf00032c r5 : ce44ff40 r4 : bf000320
r3 : bf000400 r2 : 00000fff r1 : 00000220 r0 : bf000000
Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
Control: 00093177 Table: 0e4c0000 DAC: 00000051
Process systemd-modules (pid: 89, stack limit = 0x9fccc8dc)
Stack: (0xce44fe58 to 0xce450000)
fe40: 00000000 cf1b05b8
fe60: 00000001 ce47cf08 bf002754 c07ae5d8 d0a2a484 bf002060 bf0004f8 00000000
fe80: b6d17910 c017cf1c ce47cf00 d0a29000 ce47cf00 ce44ff34 000014fc 00000000
fea0: 00000000 00000000 bf00025c 00000001 00000000 00000000 6e72656b 00006c65
fec0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
fee0: 00000000 00000000 00000000 00000000 00000000 c0ac9048 7fffffff 00000000
ff00: b6d17910 00000005 0000017b c0009208 ce44e000 00000000 b6ebfe54 c008562c
ff20: 7fffffff 00000000 00000003 cefd28f8 00000001 d0a29000 000014fc 00000000
ff40: d0a292cb d0a29380 d0a29000 000014fc d0a29f0c d0a29d90 d0a29a60 00000520
ff60: 00000710 00000718 00000826 00000000 00000000 00000000 00000708 00000023
ff80: 00000024 0000001c 00000000 00000016 00000000 c0ac9048 0041c620 00000000
ffa0: 00000000 c0009000 0041c620 00000000 00000005 b6d17910 00000000 00000000
ffc0: 0041c620 00000000 00000000 0000017b 0041f078 00000000 004098b0 b6ebfe54
ffe0: bedb6bc8 bedb6bb8 b6d0f91c b6c945a0 60000010 00000005 00000000 00000000
[<c0082930>] (frob_text.constprop.0) from [<c0084bb0>] (load_module+0x14b4/0x1d28)
[<c0084bb0>] (load_module) from [<c008562c>] (sys_finit_module+0xa0/0xc4)
[<c008562c>] (sys_finit_module) from [<c0009000>] (ret_fast_syscall+0x0/0x50)
Exception stack(0xce44ffa8 to 0xce44fff0)
ffa0: 0041c620 00000000 00000005 b6d17910 00000000 00000000
ffc0: 0041c620 00000000 00000000 0000017b 0041f078 00000000 004098b0 b6ebfe54
ffe0: bedb6bc8 bedb6bb8 b6d0f91c b6c945a0
Code: e7f001f2 e5931008 e1110002 0a000001 (e7f001f2)
---[ end trace e904557128d9aed5 ]---
This patch enables page-aligned allocation when
CONFIG_ARCH_HAS_STRICT_MODULE_RWX is enabled.
Fixes: 93651f80dcb6 ("modules: fix compile error if don't have strict module rwx")
Signed-off-by: He Zhe <[email protected]>
---
kernel/module.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/kernel/module.c b/kernel/module.c
index 5933395..9ee9342 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -65,9 +65,9 @@
/*
* Modules' sections will be aligned on page boundaries
* to ensure complete separation of code and data, but
- * only when CONFIG_STRICT_MODULE_RWX=y
+ * only when CONFIG_ARCH_HAS_STRICT_MODULE_RWX=y
*/
-#ifdef CONFIG_STRICT_MODULE_RWX
+#ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX
# define debug_align(X) ALIGN(X, PAGE_SIZE)
#else
# define debug_align(X) (X)
--
2.7.4
+++ [email protected] [10/08/19 15:22 +0800]:
>From: He Zhe <[email protected]>
>
>When loading modules with CONFIG_ARCH_HAS_STRICT_MODULE_RWX enabled and
>CONFIG_STRICT_MODULE_RWX disabled, the memory allocated for modules would
>not be page-aligned and cause the following BUG during frob_text.
>
>------------[ cut here ]------------
>kernel BUG at kernel/module.c:1907!
>Internal error: Oops - BUG: 0 [#1] ARM
>Modules linked in:
>CPU: 0 PID: 89 Comm: systemd-modules Not tainted 5.3.0-rc2 #1
>Hardware name: ARM-Versatile (Device Tree Support)
>PC is at frob_text.constprop.0+0x2c/0x40
>LR is at load_module+0x14b4/0x1d28
>pc : [<c0082930>] lr : [<c0084bb0>] psr: 20000013
>sp : ce44fe58 ip : 00000000 fp : 00000000
>r10: 00000000 r9 : ce44feb8 r8 : 00000000
>r7 : 00000001 r6 : bf00032c r5 : ce44ff40 r4 : bf000320
>r3 : bf000400 r2 : 00000fff r1 : 00000220 r0 : bf000000
>Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
>Control: 00093177 Table: 0e4c0000 DAC: 00000051
>Process systemd-modules (pid: 89, stack limit = 0x9fccc8dc)
>Stack: (0xce44fe58 to 0xce450000)
>fe40: 00000000 cf1b05b8
>fe60: 00000001 ce47cf08 bf002754 c07ae5d8 d0a2a484 bf002060 bf0004f8 00000000
>fe80: b6d17910 c017cf1c ce47cf00 d0a29000 ce47cf00 ce44ff34 000014fc 00000000
>fea0: 00000000 00000000 bf00025c 00000001 00000000 00000000 6e72656b 00006c65
>fec0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
>fee0: 00000000 00000000 00000000 00000000 00000000 c0ac9048 7fffffff 00000000
>ff00: b6d17910 00000005 0000017b c0009208 ce44e000 00000000 b6ebfe54 c008562c
>ff20: 7fffffff 00000000 00000003 cefd28f8 00000001 d0a29000 000014fc 00000000
>ff40: d0a292cb d0a29380 d0a29000 000014fc d0a29f0c d0a29d90 d0a29a60 00000520
>ff60: 00000710 00000718 00000826 00000000 00000000 00000000 00000708 00000023
>ff80: 00000024 0000001c 00000000 00000016 00000000 c0ac9048 0041c620 00000000
>ffa0: 00000000 c0009000 0041c620 00000000 00000005 b6d17910 00000000 00000000
>ffc0: 0041c620 00000000 00000000 0000017b 0041f078 00000000 004098b0 b6ebfe54
>ffe0: bedb6bc8 bedb6bb8 b6d0f91c b6c945a0 60000010 00000005 00000000 00000000
>[<c0082930>] (frob_text.constprop.0) from [<c0084bb0>] (load_module+0x14b4/0x1d28)
>[<c0084bb0>] (load_module) from [<c008562c>] (sys_finit_module+0xa0/0xc4)
>[<c008562c>] (sys_finit_module) from [<c0009000>] (ret_fast_syscall+0x0/0x50)
>Exception stack(0xce44ffa8 to 0xce44fff0)
>ffa0: 0041c620 00000000 00000005 b6d17910 00000000 00000000
>ffc0: 0041c620 00000000 00000000 0000017b 0041f078 00000000 004098b0 b6ebfe54
>ffe0: bedb6bc8 bedb6bb8 b6d0f91c b6c945a0
>Code: e7f001f2 e5931008 e1110002 0a000001 (e7f001f2)
>---[ end trace e904557128d9aed5 ]---
>
>This patch enables page-aligned allocation when
>CONFIG_ARCH_HAS_STRICT_MODULE_RWX is enabled.
>
>Fixes: 93651f80dcb6 ("modules: fix compile error if don't have strict module rwx")
>Signed-off-by: He Zhe <[email protected]>
Hi!
I have already committed a fix for this to modules-next and plan to
send a pull request next week.
Thanks!
Jessica
On 8/14/19 1:59 AM, Jessica Yu wrote:
> +++ [email protected] [10/08/19 15:22 +0800]:
>> From: He Zhe <[email protected]>
>>
>> When loading modules with CONFIG_ARCH_HAS_STRICT_MODULE_RWX enabled and
>> CONFIG_STRICT_MODULE_RWX disabled, the memory allocated for modules would
>> not be page-aligned and cause the following BUG during frob_text.
>>
>> ------------[ cut here ]------------
>> kernel BUG at kernel/module.c:1907!
>> Internal error: Oops - BUG: 0 [#1] ARM
>> Modules linked in:
>> CPU: 0 PID: 89 Comm: systemd-modules Not tainted 5.3.0-rc2 #1
>> Hardware name: ARM-Versatile (Device Tree Support)
>> PC is at frob_text.constprop.0+0x2c/0x40
>> LR is at load_module+0x14b4/0x1d28
>> pc : [<c0082930>] lr : [<c0084bb0>] psr: 20000013
>> sp : ce44fe58 ip : 00000000 fp : 00000000
>> r10: 00000000 r9 : ce44feb8 r8 : 00000000
>> r7 : 00000001 r6 : bf00032c r5 : ce44ff40 r4 : bf000320
>> r3 : bf000400 r2 : 00000fff r1 : 00000220 r0 : bf000000
>> Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
>> Control: 00093177 Table: 0e4c0000 DAC: 00000051
>> Process systemd-modules (pid: 89, stack limit = 0x9fccc8dc)
>> Stack: (0xce44fe58 to 0xce450000)
>> fe40: 00000000 cf1b05b8
>> fe60: 00000001 ce47cf08 bf002754 c07ae5d8 d0a2a484 bf002060 bf0004f8 00000000
>> fe80: b6d17910 c017cf1c ce47cf00 d0a29000 ce47cf00 ce44ff34 000014fc 00000000
>> fea0: 00000000 00000000 bf00025c 00000001 00000000 00000000 6e72656b 00006c65
>> fec0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
>> fee0: 00000000 00000000 00000000 00000000 00000000 c0ac9048 7fffffff 00000000
>> ff00: b6d17910 00000005 0000017b c0009208 ce44e000 00000000 b6ebfe54 c008562c
>> ff20: 7fffffff 00000000 00000003 cefd28f8 00000001 d0a29000 000014fc 00000000
>> ff40: d0a292cb d0a29380 d0a29000 000014fc d0a29f0c d0a29d90 d0a29a60 00000520
>> ff60: 00000710 00000718 00000826 00000000 00000000 00000000 00000708 00000023
>> ff80: 00000024 0000001c 00000000 00000016 00000000 c0ac9048 0041c620 00000000
>> ffa0: 00000000 c0009000 0041c620 00000000 00000005 b6d17910 00000000 00000000
>> ffc0: 0041c620 00000000 00000000 0000017b 0041f078 00000000 004098b0 b6ebfe54
>> ffe0: bedb6bc8 bedb6bb8 b6d0f91c b6c945a0 60000010 00000005 00000000 00000000
>> [<c0082930>] (frob_text.constprop.0) from [<c0084bb0>] (load_module+0x14b4/0x1d28)
>> [<c0084bb0>] (load_module) from [<c008562c>] (sys_finit_module+0xa0/0xc4)
>> [<c008562c>] (sys_finit_module) from [<c0009000>] (ret_fast_syscall+0x0/0x50)
>> Exception stack(0xce44ffa8 to 0xce44fff0)
>> ffa0: 0041c620 00000000 00000005 b6d17910 00000000 00000000
>> ffc0: 0041c620 00000000 00000000 0000017b 0041f078 00000000 004098b0 b6ebfe54
>> ffe0: bedb6bc8 bedb6bb8 b6d0f91c b6c945a0
>> Code: e7f001f2 e5931008 e1110002 0a000001 (e7f001f2)
>> ---[ end trace e904557128d9aed5 ]---
>>
>> This patch enables page-aligned allocation when
>> CONFIG_ARCH_HAS_STRICT_MODULE_RWX is enabled.
>>
>> Fixes: 93651f80dcb6 ("modules: fix compile error if don't have strict module rwx")
>> Signed-off-by: He Zhe <[email protected]>
>
> Hi!
>
> I have already committed a fix for this to modules-next and plan to
> send a pull request next week.
Thanks for pointing out :)
https://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux.git/commit/?h=modules-next&id=38f054d549a869f22a02224cd276a27bf14b6171
But I'd suggest we should keep the case of "define debug_align(X) (X)" for all
the rest arches without CONFIG_HAS_STRICT_MODULE_RWX ability, which would save
people who are sensitive to system size a lot of memory when using modules,
especially for embedded systems, as this patch did. This seems the original
intention of this #ifdef... statement and still valid for now.
Zhe
>
> Thanks!
>
> Jessica
>
+++ He Zhe [14/08/19 09:56 +0800]:
>
>
>On 8/14/19 1:59 AM, Jessica Yu wrote:
>> +++ [email protected] [10/08/19 15:22 +0800]:
>>> From: He Zhe <[email protected]>
>>>
>>> When loading modules with CONFIG_ARCH_HAS_STRICT_MODULE_RWX enabled and
>>> CONFIG_STRICT_MODULE_RWX disabled, the memory allocated for modules would
>>> not be page-aligned and cause the following BUG during frob_text.
>>>
>>> ------------[ cut here ]------------
>>> kernel BUG at kernel/module.c:1907!
>>> Internal error: Oops - BUG: 0 [#1] ARM
>>> Modules linked in:
>>> CPU: 0 PID: 89 Comm: systemd-modules Not tainted 5.3.0-rc2 #1
>>> Hardware name: ARM-Versatile (Device Tree Support)
>>> PC is at frob_text.constprop.0+0x2c/0x40
>>> LR is at load_module+0x14b4/0x1d28
>>> pc : [<c0082930>]??? lr : [<c0084bb0>]??? psr: 20000013
>>> sp : ce44fe58? ip : 00000000? fp : 00000000
>>> r10: 00000000? r9 : ce44feb8? r8 : 00000000
>>> r7 : 00000001? r6 : bf00032c? r5 : ce44ff40? r4 : bf000320
>>> r3 : bf000400? r2 : 00000fff? r1 : 00000220? r0 : bf000000
>>> Flags: nzCv? IRQs on? FIQs on? Mode SVC_32? ISA ARM? Segment none
>>> Control: 00093177? Table: 0e4c0000? DAC: 00000051
>>> Process systemd-modules (pid: 89, stack limit = 0x9fccc8dc)
>>> Stack: (0xce44fe58 to 0xce450000)
>>> fe40:?????????????????????????????????????????????????????? 00000000 cf1b05b8
>>> fe60: 00000001 ce47cf08 bf002754 c07ae5d8 d0a2a484 bf002060 bf0004f8 00000000
>>> fe80: b6d17910 c017cf1c ce47cf00 d0a29000 ce47cf00 ce44ff34 000014fc 00000000
>>> fea0: 00000000 00000000 bf00025c 00000001 00000000 00000000 6e72656b 00006c65
>>> fec0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
>>> fee0: 00000000 00000000 00000000 00000000 00000000 c0ac9048 7fffffff 00000000
>>> ff00: b6d17910 00000005 0000017b c0009208 ce44e000 00000000 b6ebfe54 c008562c
>>> ff20: 7fffffff 00000000 00000003 cefd28f8 00000001 d0a29000 000014fc 00000000
>>> ff40: d0a292cb d0a29380 d0a29000 000014fc d0a29f0c d0a29d90 d0a29a60 00000520
>>> ff60: 00000710 00000718 00000826 00000000 00000000 00000000 00000708 00000023
>>> ff80: 00000024 0000001c 00000000 00000016 00000000 c0ac9048 0041c620 00000000
>>> ffa0: 00000000 c0009000 0041c620 00000000 00000005 b6d17910 00000000 00000000
>>> ffc0: 0041c620 00000000 00000000 0000017b 0041f078 00000000 004098b0 b6ebfe54
>>> ffe0: bedb6bc8 bedb6bb8 b6d0f91c b6c945a0 60000010 00000005 00000000 00000000
>>> [<c0082930>] (frob_text.constprop.0) from [<c0084bb0>] (load_module+0x14b4/0x1d28)
>>> [<c0084bb0>] (load_module) from [<c008562c>] (sys_finit_module+0xa0/0xc4)
>>> [<c008562c>] (sys_finit_module) from [<c0009000>] (ret_fast_syscall+0x0/0x50)
>>> Exception stack(0xce44ffa8 to 0xce44fff0)
>>> ffa0:?????????????????? 0041c620 00000000 00000005 b6d17910 00000000 00000000
>>> ffc0: 0041c620 00000000 00000000 0000017b 0041f078 00000000 004098b0 b6ebfe54
>>> ffe0: bedb6bc8 bedb6bb8 b6d0f91c b6c945a0
>>> Code: e7f001f2 e5931008 e1110002 0a000001 (e7f001f2)
>>> ---[ end trace e904557128d9aed5 ]---
>>>
>>> This patch enables page-aligned allocation when
>>> CONFIG_ARCH_HAS_STRICT_MODULE_RWX is enabled.
>>>
>>> Fixes: 93651f80dcb6 ("modules: fix compile error if don't have strict module rwx")
>>> Signed-off-by: He Zhe <[email protected]>
>>
>> Hi!
>>
>> I have already committed a fix for this to modules-next and plan to
>> send a pull request next week.
>
>Thanks for pointing out :)
>
>https://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux.git/commit/?h=modules-next&id=38f054d549a869f22a02224cd276a27bf14b6171
>
>But I'd suggest we should keep the case of "define debug_align(X) (X)" for all
>the rest arches without CONFIG_HAS_STRICT_MODULE_RWX ability, which would save
>people who are sensitive to system size a lot of memory when using modules,
>especially for embedded systems, as this patch did. This seems the original
>intention of this #ifdef... statement and still valid for now.
>
>Zhe
Fair enough! Could you please respin this patch and base it on top of
modules-next? I would like to avoid rebasing the tree.
Thank you!
Jessica