If an load_nls_xxx() function fails a few lines above, the 'sbi->bdi_id' is
still 0.
So, in the error handling path, we will call ida_simple_remove(..., 0)
which is not allocated yet.
In order to prevent a spurious "ida_free called for id=0 which is not
allocated." message, tweak the error handling path and add a new label.
Fixes: 0fd169576648 ("fs: Add VirtualBox guest shared folder (vboxsf) support")
Signed-off-by: Christophe JAILLET <[email protected]>
---
fs/vboxsf/super.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/fs/vboxsf/super.c b/fs/vboxsf/super.c
index 1fb8f4df60cb..9848af78215b 100644
--- a/fs/vboxsf/super.c
+++ b/fs/vboxsf/super.c
@@ -151,7 +151,7 @@ static int vboxsf_fill_super(struct super_block *sb, struct fs_context *fc)
if (!sbi->nls) {
vbg_err("vboxsf: Count not load '%s' nls\n", nls_name);
err = -EINVAL;
- goto fail_free;
+ goto fail_destroy_idr;
}
}
@@ -224,6 +224,7 @@ static int vboxsf_fill_super(struct super_block *sb, struct fs_context *fc)
ida_simple_remove(&vboxsf_bdi_ida, sbi->bdi_id);
if (sbi->nls)
unload_nls(sbi->nls);
+fail_destroy_idr:
idr_destroy(&sbi->ino_idr);
kfree(sbi);
return err;
--
2.34.1
ida_alloc() and ida_free() should be preferred to the deprecated
ida_simple_get() and ida_simple_remove().
This is less verbose.
Signed-off-by: Christophe JAILLET <[email protected]>
---
fs/vboxsf/super.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/fs/vboxsf/super.c b/fs/vboxsf/super.c
index 9848af78215b..0f67f2d8b651 100644
--- a/fs/vboxsf/super.c
+++ b/fs/vboxsf/super.c
@@ -155,7 +155,7 @@ static int vboxsf_fill_super(struct super_block *sb, struct fs_context *fc)
}
}
- sbi->bdi_id = ida_simple_get(&vboxsf_bdi_ida, 0, 0, GFP_KERNEL);
+ sbi->bdi_id = ida_alloc(&vboxsf_bdi_ida, GFP_KERNEL);
if (sbi->bdi_id < 0) {
err = sbi->bdi_id;
goto fail_free;
@@ -221,7 +221,7 @@ static int vboxsf_fill_super(struct super_block *sb, struct fs_context *fc)
vboxsf_unmap_folder(sbi->root);
fail_free:
if (sbi->bdi_id >= 0)
- ida_simple_remove(&vboxsf_bdi_ida, sbi->bdi_id);
+ ida_free(&vboxsf_bdi_ida, sbi->bdi_id);
if (sbi->nls)
unload_nls(sbi->nls);
fail_destroy_idr:
@@ -269,7 +269,7 @@ static void vboxsf_put_super(struct super_block *sb)
vboxsf_unmap_folder(sbi->root);
if (sbi->bdi_id >= 0)
- ida_simple_remove(&vboxsf_bdi_ida, sbi->bdi_id);
+ ida_free(&vboxsf_bdi_ida, sbi->bdi_id);
if (sbi->nls)
unload_nls(sbi->nls);
--
2.34.1
Hi Christophe,
On 11/1/23 11:49, Christophe JAILLET wrote:
> If an load_nls_xxx() function fails a few lines above, the 'sbi->bdi_id' is
> still 0.
> So, in the error handling path, we will call ida_simple_remove(..., 0)
> which is not allocated yet.
>
> In order to prevent a spurious "ida_free called for id=0 which is not
> allocated." message, tweak the error handling path and add a new label.
>
> Fixes: 0fd169576648 ("fs: Add VirtualBox guest shared folder (vboxsf) support")
> Signed-off-by: Christophe JAILLET <[email protected]>
Thank you, both patches look good to me:
Reviewed-by: Hans de Goede <[email protected]>
for the series.
Regards,
Hans
> ---
> fs/vboxsf/super.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/fs/vboxsf/super.c b/fs/vboxsf/super.c
> index 1fb8f4df60cb..9848af78215b 100644
> --- a/fs/vboxsf/super.c
> +++ b/fs/vboxsf/super.c
> @@ -151,7 +151,7 @@ static int vboxsf_fill_super(struct super_block *sb, struct fs_context *fc)
> if (!sbi->nls) {
> vbg_err("vboxsf: Count not load '%s' nls\n", nls_name);
> err = -EINVAL;
> - goto fail_free;
> + goto fail_destroy_idr;
> }
> }
>
> @@ -224,6 +224,7 @@ static int vboxsf_fill_super(struct super_block *sb, struct fs_context *fc)
> ida_simple_remove(&vboxsf_bdi_ida, sbi->bdi_id);
> if (sbi->nls)
> unload_nls(sbi->nls);
> +fail_destroy_idr:
> idr_destroy(&sbi->ino_idr);
> kfree(sbi);
> return err;
On Wed, Nov 01, 2023 at 11:49:48AM +0100, Christophe JAILLET wrote:
> If an load_nls_xxx() function fails a few lines above, the 'sbi->bdi_id' is
> still 0.
> So, in the error handling path, we will call ida_simple_remove(..., 0)
> which is not allocated yet.
>
> In order to prevent a spurious "ida_free called for id=0 which is not
> allocated." message, tweak the error handling path and add a new label.
That's not spurious! You're freeing something that wasn't allocated.
A good quality malloc allocation will warn you if you free() a random
pointer. I agree with everything abuot this patch (and the next) except
for the changelog.
> Fixes: 0fd169576648 ("fs: Add VirtualBox guest shared folder (vboxsf) support")
> Signed-off-by: Christophe JAILLET <[email protected]>
> ---
> fs/vboxsf/super.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/fs/vboxsf/super.c b/fs/vboxsf/super.c
> index 1fb8f4df60cb..9848af78215b 100644
> --- a/fs/vboxsf/super.c
> +++ b/fs/vboxsf/super.c
> @@ -151,7 +151,7 @@ static int vboxsf_fill_super(struct super_block *sb, struct fs_context *fc)
> if (!sbi->nls) {
> vbg_err("vboxsf: Count not load '%s' nls\n", nls_name);
> err = -EINVAL;
> - goto fail_free;
> + goto fail_destroy_idr;
> }
> }
>
> @@ -224,6 +224,7 @@ static int vboxsf_fill_super(struct super_block *sb, struct fs_context *fc)
> ida_simple_remove(&vboxsf_bdi_ida, sbi->bdi_id);
> if (sbi->nls)
> unload_nls(sbi->nls);
> +fail_destroy_idr:
> idr_destroy(&sbi->ino_idr);
> kfree(sbi);
> return err;
> --
> 2.34.1
>
>
Le 02/11/2023 à 13:30, Matthew Wilcox a écrit :
> On Wed, Nov 01, 2023 at 11:49:48AM +0100, Christophe JAILLET wrote:
>> If an load_nls_xxx() function fails a few lines above, the 'sbi->bdi_id' is
>> still 0.
>> So, in the error handling path, we will call ida_simple_remove(..., 0)
>> which is not allocated yet.
>>
>> In order to prevent a spurious "ida_free called for id=0 which is not
>> allocated." message, tweak the error handling path and add a new label.
>
> That's not spurious!
My fault, as a non-native English speaking man.
I've always sought that spurious was meaning "odd" or "strange", but I
was wrong :(
Here, a better wording could be "to prevent an un-expected "ida..."".
Is that ok for you?
Or the last sentence could shortened to only "In order to fix it, tweak
the error handling path and add a new label.".
CJ
> You're freeing something that wasn't allocated.
> A good quality malloc allocation will warn you if you free() a random
> pointer. I agree with everything abuot this patch (and the next) except
> for the changelog.
>
>> Fixes: 0fd169576648 ("fs: Add VirtualBox guest shared folder (vboxsf) support")
>> Signed-off-by: Christophe JAILLET <[email protected]>
>> ---
>> fs/vboxsf/super.c | 3 ++-
>> 1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/fs/vboxsf/super.c b/fs/vboxsf/super.c
>> index 1fb8f4df60cb..9848af78215b 100644
>> --- a/fs/vboxsf/super.c
>> +++ b/fs/vboxsf/super.c
>> @@ -151,7 +151,7 @@ static int vboxsf_fill_super(struct super_block *sb, struct fs_context *fc)
>> if (!sbi->nls) {
>> vbg_err("vboxsf: Count not load '%s' nls\n", nls_name);
>> err = -EINVAL;
>> - goto fail_free;
>> + goto fail_destroy_idr;
>> }
>> }
>>
>> @@ -224,6 +224,7 @@ static int vboxsf_fill_super(struct super_block *sb, struct fs_context *fc)
>> ida_simple_remove(&vboxsf_bdi_ida, sbi->bdi_id);
>> if (sbi->nls)
>> unload_nls(sbi->nls);
>> +fail_destroy_idr:
>> idr_destroy(&sbi->ino_idr);
>> kfree(sbi);
>> return err;
>> --
>> 2.34.1
>>
>>
>
>
Hi,
On 11/1/23 11:49 AM, Christophe JAILLET wrote:
> If an load_nls_xxx() function fails a few lines above, the 'sbi->bdi_id' is
> still 0.
> So, in the error handling path, we will call ida_simple_remove(..., 0)
> which is not allocated yet.
>
> In order to prevent a spurious "ida_free called for id=0 which is not
> allocated." message, tweak the error handling path and add a new label.
>
> Fixes: 0fd169576648 ("fs: Add VirtualBox guest shared folder (vboxsf) support")
> Signed-off-by: Christophe JAILLET <[email protected]>
Thanks, both patches in this series look good to me:
Reviewed-by: Hans de Goede <[email protected]>
I have added both patches to my local vboxsf branch now and I'll send
out a pull-request with this and a couple of other vboxsf fixes
soon.
Regards,
Hans
> ---
> fs/vboxsf/super.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/fs/vboxsf/super.c b/fs/vboxsf/super.c
> index 1fb8f4df60cb..9848af78215b 100644
> --- a/fs/vboxsf/super.c
> +++ b/fs/vboxsf/super.c
> @@ -151,7 +151,7 @@ static int vboxsf_fill_super(struct super_block *sb, struct fs_context *fc)
> if (!sbi->nls) {
> vbg_err("vboxsf: Count not load '%s' nls\n", nls_name);
> err = -EINVAL;
> - goto fail_free;
> + goto fail_destroy_idr;
> }
> }
>
> @@ -224,6 +224,7 @@ static int vboxsf_fill_super(struct super_block *sb, struct fs_context *fc)
> ida_simple_remove(&vboxsf_bdi_ida, sbi->bdi_id);
> if (sbi->nls)
> unload_nls(sbi->nls);
> +fail_destroy_idr:
> idr_destroy(&sbi->ino_idr);
> kfree(sbi);
> return err;