2020-06-01 09:14:19

by Zhihao Cheng

Subject: [PATCH] ubi: fastmap: Don't produce the initial anchor PEB when fastmap is disabled

Following process triggers a memleak caused by forgetting to release the
initial anchor PEB (CONFIG_MTD_UBI_FASTMAP is disabled):
1. attach -> __erase_worker -> produce the initial anchor PEB
2. detach -> ubi_fastmap_close (Do nothing, it should have released the
initial anchor PEB)

Don't produce the initial anchor PEB in __erase_worker() when fastmap
is disabled.

Signed-off-by: Zhihao Cheng <[email protected]>
Fixes: f9c34bb529975fe ("ubi: Fix producing anchor PEBs")
Reported-by: [email protected]
---
drivers/mtd/ubi/wl.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c
index 5146cce5fe32..5ebe1084a8e7 100644
--- a/drivers/mtd/ubi/wl.c
+++ b/drivers/mtd/ubi/wl.c
@@ -1079,13 +1079,19 @@ static int __erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk)
if (!err) {
spin_lock(&ubi->wl_lock);

- if (!ubi->fm_anchor && e->pnum < UBI_FM_MAX_START) {
+#ifdef CONFIG_MTD_UBI_FASTMAP
+ if (!ubi->fm_disabled && !ubi->fm_anchor &&
+ e->pnum < UBI_FM_MAX_START) {
ubi->fm_anchor = e;
ubi->fm_do_produce_anchor = 0;
} else {
wl_tree_add(e, &ubi->free);
ubi->free_count++;
}
+#else
+ wl_tree_add(e, &ubi->free);
+ ubi->free_count++;
+#endif

spin_unlock(&ubi->wl_lock);

--
2.25.4

2020-06-02 09:25:55

by Sascha Hauer

Subject: Re: [PATCH] ubi: fastmap: Don't produce the initial anchor PEB when fastmap is disabled

Hi,

On Mon, Jun 01, 2020 at 05:11:34PM +0800, Zhihao Cheng wrote:
> Following process triggers a memleak caused by forgetting to release the
> initial anchor PEB (CONFIG_MTD_UBI_FASTMAP is disabled):
> 1. attach -> __erase_worker -> produce the initial anchor PEB
> 2. detach -> ubi_fastmap_close (Do nothing, it should have released the
> initial anchor PEB)
>
> Don't produce the initial anchor PEB in __erase_worker() when fastmap
> is disabled.
>
> Signed-off-by: Zhihao Cheng <[email protected]>
> Fixes: f9c34bb529975fe ("ubi: Fix producing anchor PEBs")
> Reported-by: [email protected]
> ---
> drivers/mtd/ubi/wl.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c
> index 5146cce5fe32..5ebe1084a8e7 100644
> --- a/drivers/mtd/ubi/wl.c
> +++ b/drivers/mtd/ubi/wl.c
> @@ -1079,13 +1079,19 @@ static int __erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk)
> if (!err) {
> spin_lock(&ubi->wl_lock);
>
> - if (!ubi->fm_anchor && e->pnum < UBI_FM_MAX_START) {
> +#ifdef CONFIG_MTD_UBI_FASTMAP
> + if (!ubi->fm_disabled && !ubi->fm_anchor &&
> + e->pnum < UBI_FM_MAX_START) {

Rather than introducing another #ifdef you could do a

if (IS_ENABLED(CONFIG_MTD_UBI_FASTMAP) &&
!ubi->fm_disabled && !ubi->fm_anchor &&
e->pnum < UBI_FM_MAX_START)

And I am not sure if the IS_ENABLED(CONFIG_MTD_UBI_FASTMAP) is necessary
at all because we do a ubi->fm_disabled = 1 when fastmap is disabled.

Regards,
Sascha

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2020-06-02 11:17:01

by Zhihao Cheng

Subject: Re: [PATCH] ubi: fastmap: Don't produce the initial anchor PEB when fastmap is disabled

?? 2020/6/2 17:23, Sascha Hauer д??:
> Hi,
>
> On Mon, Jun 01, 2020 at 05:11:34PM +0800, Zhihao Cheng wrote:
>> Following process triggers a memleak caused by forgetting to release the
>> initial anchor PEB (CONFIG_MTD_UBI_FASTMAP is disabled):
>> 1. attach -> __erase_worker -> produce the initial anchor PEB
>> 2. detach -> ubi_fastmap_close (Do nothing, it should have released the
>> initial anchor PEB)
>>
>> Don't produce the initial anchor PEB in __erase_worker() when fastmap
>> is disabled.
>>
>> Signed-off-by: Zhihao Cheng <[email protected]>
>> Fixes: f9c34bb529975fe ("ubi: Fix producing anchor PEBs")
>> Reported-by: [email protected]
>> ---
>> drivers/mtd/ubi/wl.c | 8 +++++++-
>> 1 file changed, 7 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c
>> index 5146cce5fe32..5ebe1084a8e7 100644
>> --- a/drivers/mtd/ubi/wl.c
>> +++ b/drivers/mtd/ubi/wl.c
>> @@ -1079,13 +1079,19 @@ static int __erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk)
>> if (!err) {
>> spin_lock(&ubi->wl_lock);
>>
>> - if (!ubi->fm_anchor && e->pnum < UBI_FM_MAX_START) {
>> +#ifdef CONFIG_MTD_UBI_FASTMAP
>> + if (!ubi->fm_disabled && !ubi->fm_anchor &&
>> + e->pnum < UBI_FM_MAX_START) {
> Rather than introducing another #ifdef you could do a
>
> if (IS_ENABLED(CONFIG_MTD_UBI_FASTMAP) &&
> !ubi->fm_disabled && !ubi->fm_anchor &&
> e->pnum < UBI_FM_MAX_START)
>
> And I am not sure if the IS_ENABLED(CONFIG_MTD_UBI_FASTMAP) is necessary
> at all because we do a ubi->fm_disabled = 1 when fastmap is disabled.
>
> Regards,
> Sascha
>
Agree.