2022-04-18 11:47:54

by Md Sadre Alam

[permalink] [raw]
Subject: [PATCH V4] mtd: rawnand: qcom: fix memory corruption that causes panic

This patch fixes a memory corruption that occurred in the
nand_scan() path for Hynix nand device.

On boot, for Hynix nand device will panic at a weird place:
| Unable to handle kernel NULL pointer dereference at virtual
address 00000070
| [00000070] *pgd=00000000
| Internal error: Oops: 5 [#1] PREEMPT SMP ARM
| Modules linked in:
| CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.17.0-01473-g13ae1769cfb0
#38
| Hardware name: Generic DT based system
| PC is at nandc_set_reg+0x8/0x1c
| LR is at qcom_nandc_command+0x20c/0x5d0
| pc : [<c088b74c>] lr : [<c088d9c8>] psr: 00000113
| sp : c14adc50 ip : c14ee208 fp : c0cc970c
| r10: 000000a3 r9 : 00000000 r8 : 00000040
| r7 : c16f6a00 r6 : 00000090 r5 : 00000004 r4 :c14ee040
| r3 : 00000000 r2 : 0000000b r1 : 00000000 r0 :c14ee040
| Flags: nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
| Control: 10c5387d Table: 8020406a DAC: 00000051
| Register r0 information: slab kmalloc-2k start c14ee000 pointer offset
64 size 2048
| Process swapper/0 (pid: 1, stack limit = 0x(ptrval))
| nandc_set_reg from qcom_nandc_command+0x20c/0x5d0
| qcom_nandc_command from nand_readid_op+0x198/0x1e8
| nand_readid_op from hynix_nand_has_valid_jedecid+0x30/0x78
| hynix_nand_has_valid_jedecid from hynix_nand_init+0xb8/0x454
| hynix_nand_init from nand_scan_with_ids+0xa30/0x14a8
| nand_scan_with_ids from qcom_nandc_probe+0x648/0x7b0
| qcom_nandc_probe from platform_probe+0x58/0xac

The problem is that the nand_scan()'s qcom_nand_attach_chip callback
is updating the nandc->max_cwperpage from 1 to 4 or 8 based on page size.
This causes the sg_init_table of clear_bam_transaction() in the driver's
qcom_nandc_command() to memset much more than what was initially
allocated by alloc_bam_transaction().

This patch will update nandc->max_cwperpage 1 to 4 or 8 based on page
size in qcom_nand_attach_chip call back after freeing the previously
allocated memory for bam txn as per nandc->max_cwperpage = 1 and then
again allocating bam txn as per nandc->max_cwperpage = 4 or 8 based on
page size in qcom_nand_attach_chip call back itself.

Cc: [email protected]
Fixes: 6a3cec64f18c ("mtd: rawnand: qcom: convert driver to nand_scan()")
Reported-by: Konrad Dybcio <[email protected]>
Signed-off-by: Md Sadre Alam <[email protected]>
Signed-off-by: Sricharan R <[email protected]>
---
Changes in V4:

* Incorporated "commit log wrong" comment from Mani
* Updated commit log

Changes in V3:

* Incorporated "Fixes tags are missing" comment from Miquèl
* Added Fixes tag Fixes:6a3cec64f18c ("mtd: rawnand: qcom: convert driver to nand_scan()")
* Incorporated "stable tag missing" comment from Miquèl
* Added stable tag Cc: [email protected]
* Incorporated "Reported-by tag missing" comment from Mani
* Added Reported-by tag Reported-by: Konrad Dybcio <[email protected]>

Changes in V2:

* Incorporated "alloc_bam_transaction inside qcom_nand_attach_chip" suggestion from Mani
* Freed previously alloacted memory for bam txn before updating max_cwperpage inside
qcom_nand_attach_chip().
* Moved alloc_bam_transaction() inside qcom_nand_attach_chip(). after upding max_cwperpage
4 or 8 based on page size.

drivers/mtd/nand/raw/qcom_nandc.c | 24 +++++++++++++-----------
1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/drivers/mtd/nand/raw/qcom_nandc.c b/drivers/mtd/nand/raw/qcom_nandc.c
index 1a77542..048b255 100644
--- a/drivers/mtd/nand/raw/qcom_nandc.c
+++ b/drivers/mtd/nand/raw/qcom_nandc.c
@@ -2651,10 +2651,23 @@ static int qcom_nand_attach_chip(struct nand_chip *chip)
ecc->engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST;

mtd_set_ooblayout(mtd, &qcom_nand_ooblayout_ops);
+ /* Free the initially allocated BAM transaction for reading the ONFI params */
+ if (nandc->props->is_bam)
+ free_bam_transaction(nandc);

nandc->max_cwperpage = max_t(unsigned int, nandc->max_cwperpage,
cwperpage);

+ /* Now allocate the BAM transaction based on updated max_cwperpage */
+ if (nandc->props->is_bam) {
+ nandc->bam_txn = alloc_bam_transaction(nandc);
+ if (!nandc->bam_txn) {
+ dev_err(nandc->dev,
+ "failed to allocate bam transaction\n");
+ return -ENOMEM;
+ }
+ }
+
/*
* DATA_UD_BYTES varies based on whether the read/write command protects
* spare data with ECC too. We protect spare data by default, so we set
@@ -2955,17 +2968,6 @@ static int qcom_nand_host_init_and_register(struct qcom_nand_controller *nandc,
if (ret)
return ret;

- if (nandc->props->is_bam) {
- free_bam_transaction(nandc);
- nandc->bam_txn = alloc_bam_transaction(nandc);
- if (!nandc->bam_txn) {
- dev_err(nandc->dev,
- "failed to allocate bam transaction\n");
- nand_cleanup(chip);
- return -ENOMEM;
- }
- }
-
ret = mtd_device_parse_register(mtd, probes, NULL, NULL, 0);
if (ret)
nand_cleanup(chip);
--
2.7.4


2022-04-18 12:32:08

by Manivannan Sadhasivam

[permalink] [raw]
Subject: Re: [PATCH V4] mtd: rawnand: qcom: fix memory corruption that causes panic

On Mon, Apr 18, 2022 at 11:53:11AM +0530, Md Sadre Alam wrote:
> This patch fixes a memory corruption that occurred in the
> nand_scan() path for Hynix nand device.
>
> On boot, for Hynix nand device will panic at a weird place:
> | Unable to handle kernel NULL pointer dereference at virtual
> address 00000070
> | [00000070] *pgd=00000000
> | Internal error: Oops: 5 [#1] PREEMPT SMP ARM
> | Modules linked in:
> | CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.17.0-01473-g13ae1769cfb0
> #38
> | Hardware name: Generic DT based system
> | PC is at nandc_set_reg+0x8/0x1c
> | LR is at qcom_nandc_command+0x20c/0x5d0
> | pc : [<c088b74c>] lr : [<c088d9c8>] psr: 00000113
> | sp : c14adc50 ip : c14ee208 fp : c0cc970c
> | r10: 000000a3 r9 : 00000000 r8 : 00000040
> | r7 : c16f6a00 r6 : 00000090 r5 : 00000004 r4 :c14ee040
> | r3 : 00000000 r2 : 0000000b r1 : 00000000 r0 :c14ee040
> | Flags: nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
> | Control: 10c5387d Table: 8020406a DAC: 00000051
> | Register r0 information: slab kmalloc-2k start c14ee000 pointer offset
> 64 size 2048
> | Process swapper/0 (pid: 1, stack limit = 0x(ptrval))
> | nandc_set_reg from qcom_nandc_command+0x20c/0x5d0
> | qcom_nandc_command from nand_readid_op+0x198/0x1e8
> | nand_readid_op from hynix_nand_has_valid_jedecid+0x30/0x78
> | hynix_nand_has_valid_jedecid from hynix_nand_init+0xb8/0x454
> | hynix_nand_init from nand_scan_with_ids+0xa30/0x14a8
> | nand_scan_with_ids from qcom_nandc_probe+0x648/0x7b0
> | qcom_nandc_probe from platform_probe+0x58/0xac
>
> The problem is that the nand_scan()'s qcom_nand_attach_chip callback
> is updating the nandc->max_cwperpage from 1 to 4 or 8 based on page size.
> This causes the sg_init_table of clear_bam_transaction() in the driver's
> qcom_nandc_command() to memset much more than what was initially
> allocated by alloc_bam_transaction().
>
> This patch will update nandc->max_cwperpage 1 to 4 or 8 based on page
> size in qcom_nand_attach_chip call back after freeing the previously
> allocated memory for bam txn as per nandc->max_cwperpage = 1 and then
> again allocating bam txn as per nandc->max_cwperpage = 4 or 8 based on
> page size in qcom_nand_attach_chip call back itself.
>
> Cc: [email protected]
> Fixes: 6a3cec64f18c ("mtd: rawnand: qcom: convert driver to nand_scan()")
> Reported-by: Konrad Dybcio <[email protected]>
> Signed-off-by: Md Sadre Alam <[email protected]>
> Signed-off-by: Sricharan R <[email protected]>

I know that you and Sri were involved in creating this patch. So there should
be a co-developed-by tag for Sri and your signed-off-by should be the last one.
Like below,

Cc: [email protected]
Fixes: 6a3cec64f18c ("mtd: rawnand: qcom: convert driver to nand_scan()")
Reported-by: Konrad Dybcio <[email protected]>
Co-developed-by: Sricharan R <[email protected]>
Signed-off-by: Sricharan R <[email protected]>
Signed-off-by: Md Sadre Alam <[email protected]>

With that,

Reviewed-by: Manivannan Sadhasivam <[email protected]>

Thanks,
Mani

> ---
> Changes in V4:
>
> * Incorporated "commit log wrong" comment from Mani
> * Updated commit log
>
> Changes in V3:
>
> * Incorporated "Fixes tags are missing" comment from Miqu?l
> * Added Fixes tag Fixes:6a3cec64f18c ("mtd: rawnand: qcom: convert driver to nand_scan()")
> * Incorporated "stable tag missing" comment from Miqu?l
> * Added stable tag Cc: [email protected]
> * Incorporated "Reported-by tag missing" comment from Mani
> * Added Reported-by tag Reported-by: Konrad Dybcio <[email protected]>
>
> Changes in V2:
>
> * Incorporated "alloc_bam_transaction inside qcom_nand_attach_chip" suggestion from Mani
> * Freed previously alloacted memory for bam txn before updating max_cwperpage inside
> qcom_nand_attach_chip().
> * Moved alloc_bam_transaction() inside qcom_nand_attach_chip(). after upding max_cwperpage
> 4 or 8 based on page size.
>
> drivers/mtd/nand/raw/qcom_nandc.c | 24 +++++++++++++-----------
> 1 file changed, 13 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/mtd/nand/raw/qcom_nandc.c b/drivers/mtd/nand/raw/qcom_nandc.c
> index 1a77542..048b255 100644
> --- a/drivers/mtd/nand/raw/qcom_nandc.c
> +++ b/drivers/mtd/nand/raw/qcom_nandc.c
> @@ -2651,10 +2651,23 @@ static int qcom_nand_attach_chip(struct nand_chip *chip)
> ecc->engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST;
>
> mtd_set_ooblayout(mtd, &qcom_nand_ooblayout_ops);
> + /* Free the initially allocated BAM transaction for reading the ONFI params */
> + if (nandc->props->is_bam)
> + free_bam_transaction(nandc);
>
> nandc->max_cwperpage = max_t(unsigned int, nandc->max_cwperpage,
> cwperpage);
>
> + /* Now allocate the BAM transaction based on updated max_cwperpage */
> + if (nandc->props->is_bam) {
> + nandc->bam_txn = alloc_bam_transaction(nandc);
> + if (!nandc->bam_txn) {
> + dev_err(nandc->dev,
> + "failed to allocate bam transaction\n");
> + return -ENOMEM;
> + }
> + }
> +
> /*
> * DATA_UD_BYTES varies based on whether the read/write command protects
> * spare data with ECC too. We protect spare data by default, so we set
> @@ -2955,17 +2968,6 @@ static int qcom_nand_host_init_and_register(struct qcom_nand_controller *nandc,
> if (ret)
> return ret;
>
> - if (nandc->props->is_bam) {
> - free_bam_transaction(nandc);
> - nandc->bam_txn = alloc_bam_transaction(nandc);
> - if (!nandc->bam_txn) {
> - dev_err(nandc->dev,
> - "failed to allocate bam transaction\n");
> - nand_cleanup(chip);
> - return -ENOMEM;
> - }
> - }
> -
> ret = mtd_device_parse_register(mtd, probes, NULL, NULL, 0);
> if (ret)
> nand_cleanup(chip);
> --
> 2.7.4
>

2022-04-18 17:52:36

by Md Sadre Alam

[permalink] [raw]
Subject: Re: [PATCH V4] mtd: rawnand: qcom: fix memory corruption that causes panic


On 4/18/2022 12:06 PM, Manivannan Sadhasivam wrote:
> On Mon, Apr 18, 2022 at 11:53:11AM +0530, Md Sadre Alam wrote:
>> This patch fixes a memory corruption that occurred in the
>> nand_scan() path for Hynix nand device.
>>
>> On boot, for Hynix nand device will panic at a weird place:
>> | Unable to handle kernel NULL pointer dereference at virtual
>> address 00000070
>> | [00000070] *pgd=00000000
>> | Internal error: Oops: 5 [#1] PREEMPT SMP ARM
>> | Modules linked in:
>> | CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.17.0-01473-g13ae1769cfb0
>> #38
>> | Hardware name: Generic DT based system
>> | PC is at nandc_set_reg+0x8/0x1c
>> | LR is at qcom_nandc_command+0x20c/0x5d0
>> | pc : [<c088b74c>] lr : [<c088d9c8>] psr: 00000113
>> | sp : c14adc50 ip : c14ee208 fp : c0cc970c
>> | r10: 000000a3 r9 : 00000000 r8 : 00000040
>> | r7 : c16f6a00 r6 : 00000090 r5 : 00000004 r4 :c14ee040
>> | r3 : 00000000 r2 : 0000000b r1 : 00000000 r0 :c14ee040
>> | Flags: nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
>> | Control: 10c5387d Table: 8020406a DAC: 00000051
>> | Register r0 information: slab kmalloc-2k start c14ee000 pointer offset
>> 64 size 2048
>> | Process swapper/0 (pid: 1, stack limit = 0x(ptrval))
>> | nandc_set_reg from qcom_nandc_command+0x20c/0x5d0
>> | qcom_nandc_command from nand_readid_op+0x198/0x1e8
>> | nand_readid_op from hynix_nand_has_valid_jedecid+0x30/0x78
>> | hynix_nand_has_valid_jedecid from hynix_nand_init+0xb8/0x454
>> | hynix_nand_init from nand_scan_with_ids+0xa30/0x14a8
>> | nand_scan_with_ids from qcom_nandc_probe+0x648/0x7b0
>> | qcom_nandc_probe from platform_probe+0x58/0xac
>>
>> The problem is that the nand_scan()'s qcom_nand_attach_chip callback
>> is updating the nandc->max_cwperpage from 1 to 4 or 8 based on page size.
>> This causes the sg_init_table of clear_bam_transaction() in the driver's
>> qcom_nandc_command() to memset much more than what was initially
>> allocated by alloc_bam_transaction().
>>
>> This patch will update nandc->max_cwperpage 1 to 4 or 8 based on page
>> size in qcom_nand_attach_chip call back after freeing the previously
>> allocated memory for bam txn as per nandc->max_cwperpage = 1 and then
>> again allocating bam txn as per nandc->max_cwperpage = 4 or 8 based on
>> page size in qcom_nand_attach_chip call back itself.
>>
>> Cc: [email protected]
>> Fixes: 6a3cec64f18c ("mtd: rawnand: qcom: convert driver to nand_scan()")
>> Reported-by: Konrad Dybcio <[email protected]>
>> Signed-off-by: Md Sadre Alam <[email protected]>
>> Signed-off-by: Sricharan R <[email protected]>
> I know that you and Sri were involved in creating this patch. So there should
> be a co-developed-by tag for Sri and your signed-off-by should be the last one.
> Like below,
    Updated in V5 patch.
>
> Cc: [email protected]
> Fixes: 6a3cec64f18c ("mtd: rawnand: qcom: convert driver to nand_scan()")
> Reported-by: Konrad Dybcio <[email protected]>
> Co-developed-by: Sricharan R <[email protected]>
> Signed-off-by: Sricharan R <[email protected]>
> Signed-off-by: Md Sadre Alam <[email protected]>
>
> With that,
>
> Reviewed-by: Manivannan Sadhasivam <[email protected]>


  Updated in V5 patch.

>
> Thanks,
> Mani
>
>> ---
>> Changes in V4:
>>
>> * Incorporated "commit log wrong" comment from Mani
>> * Updated commit log
>>
>> Changes in V3:
>>
>> * Incorporated "Fixes tags are missing" comment from Miquèl
>> * Added Fixes tag Fixes:6a3cec64f18c ("mtd: rawnand: qcom: convert driver to nand_scan()")
>> * Incorporated "stable tag missing" comment from Miquèl
>> * Added stable tag Cc: [email protected]
>> * Incorporated "Reported-by tag missing" comment from Mani
>> * Added Reported-by tag Reported-by: Konrad Dybcio <[email protected]>
>>
>> Changes in V2:
>>
>> * Incorporated "alloc_bam_transaction inside qcom_nand_attach_chip" suggestion from Mani
>> * Freed previously alloacted memory for bam txn before updating max_cwperpage inside
>> qcom_nand_attach_chip().
>> * Moved alloc_bam_transaction() inside qcom_nand_attach_chip(). after upding max_cwperpage
>> 4 or 8 based on page size.
>>
>> drivers/mtd/nand/raw/qcom_nandc.c | 24 +++++++++++++-----------
>> 1 file changed, 13 insertions(+), 11 deletions(-)
>>
>> diff --git a/drivers/mtd/nand/raw/qcom_nandc.c b/drivers/mtd/nand/raw/qcom_nandc.c
>> index 1a77542..048b255 100644
>> --- a/drivers/mtd/nand/raw/qcom_nandc.c
>> +++ b/drivers/mtd/nand/raw/qcom_nandc.c
>> @@ -2651,10 +2651,23 @@ static int qcom_nand_attach_chip(struct nand_chip *chip)
>> ecc->engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST;
>>
>> mtd_set_ooblayout(mtd, &qcom_nand_ooblayout_ops);
>> + /* Free the initially allocated BAM transaction for reading the ONFI params */
>> + if (nandc->props->is_bam)
>> + free_bam_transaction(nandc);
>>
>> nandc->max_cwperpage = max_t(unsigned int, nandc->max_cwperpage,
>> cwperpage);
>>
>> + /* Now allocate the BAM transaction based on updated max_cwperpage */
>> + if (nandc->props->is_bam) {
>> + nandc->bam_txn = alloc_bam_transaction(nandc);
>> + if (!nandc->bam_txn) {
>> + dev_err(nandc->dev,
>> + "failed to allocate bam transaction\n");
>> + return -ENOMEM;
>> + }
>> + }
>> +
>> /*
>> * DATA_UD_BYTES varies based on whether the read/write command protects
>> * spare data with ECC too. We protect spare data by default, so we set
>> @@ -2955,17 +2968,6 @@ static int qcom_nand_host_init_and_register(struct qcom_nand_controller *nandc,
>> if (ret)
>> return ret;
>>
>> - if (nandc->props->is_bam) {
>> - free_bam_transaction(nandc);
>> - nandc->bam_txn = alloc_bam_transaction(nandc);
>> - if (!nandc->bam_txn) {
>> - dev_err(nandc->dev,
>> - "failed to allocate bam transaction\n");
>> - nand_cleanup(chip);
>> - return -ENOMEM;
>> - }
>> - }
>> -
>> ret = mtd_device_parse_register(mtd, probes, NULL, NULL, 0);
>> if (ret)
>> nand_cleanup(chip);
>> --
>> 2.7.4
>>