[PATCH v2] pstore: fix crypto dependencies without compression

[PATCH v2] pstore: fix crypto dependencies without compression

[Tobias Regnery]

Commit 58eb5b670747 ("pstore: fix crypto dependencies") fixed up the crypto
dependencies but missed the case when no compression is selected.

With CONFIG_PSTORE=y, CONFIG_PSTORE_COMPRESS=n  and CONFIG_CRYPTO=m we see
the following link error:

fs/pstore/platform.o: In function `pstore_register':
(.text+0x1b1): undefined reference to `crypto_has_alg'
(.text+0x205): undefined reference to `crypto_alloc_base'
fs/pstore/platform.o: In function `pstore_unregister':
(.text+0x3b0): undefined reference to `crypto_destroy_tfm'

Fix this by checking at compile-time if CONFIG_PSTORE_COMPRESS is enabled.

Fixes: 58eb5b670747 ("pstore: fix crypto dependencies")
Signed-off-by: Tobias Regnery <tobias.regnery@gmail.com>
---
v2: check the config at compile-time rather than change the 
    kconfig-dependency as suggested by Arnd.

---
 fs/pstore/platform.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index 1143ef351c58..dc720573fd53 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -258,7 +258,7 @@ static int pstore_decompress(void *in, void *out,
 
 static void allocate_buf_for_compression(void)
 {
-	if (!zbackend)
+	if (!IS_ENABLED(CONFIG_PSTORE_COMPRESS) || !zbackend)
 		return;
 
 	if (!crypto_has_comp(zbackend->name, 0, 0)) {
@@ -287,7 +287,7 @@ static void allocate_buf_for_compression(void)
 
 static void free_buf_for_compression(void)
 {
-	if (!IS_ERR_OR_NULL(tfm))
+	if (IS_ENABLED(CONFIG_PSTORE_COMPRESS) && !IS_ERR_OR_NULL(tfm))
 		crypto_free_comp(tfm);
 	kfree(big_oops_buf);
 	big_oops_buf = NULL;
-- 
2.16.3

Re: [PATCH v2] pstore: fix crypto dependencies without compression

[Arnd Bergmann]

On Fri, Apr 6, 2018 at 9:25 AM, Tobias Regnery <tobias.regnery@gmail.com> wrote:
> Commit 58eb5b670747 ("pstore: fix crypto dependencies") fixed up the crypto
> dependencies but missed the case when no compression is selected.
>
> With CONFIG_PSTORE=y, CONFIG_PSTORE_COMPRESS=n  and CONFIG_CRYPTO=m we see
> the following link error:
>
> fs/pstore/platform.o: In function `pstore_register':
> (.text+0x1b1): undefined reference to `crypto_has_alg'
> (.text+0x205): undefined reference to `crypto_alloc_base'
> fs/pstore/platform.o: In function `pstore_unregister':
> (.text+0x3b0): undefined reference to `crypto_destroy_tfm'
>
> Fix this by checking at compile-time if CONFIG_PSTORE_COMPRESS is enabled.
>
> Fixes: 58eb5b670747 ("pstore: fix crypto dependencies")
> Signed-off-by: Tobias Regnery <tobias.regnery@gmail.com>
> ---
> v2: check the config at compile-time rather than change the
>     kconfig-dependency as suggested by Arnd.

Thanks!

Acked-by: Arnd Bergmann <arnd@arndb.de>

Re: [PATCH v2] pstore: fix crypto dependencies without compression

[Kees Cook]

On Fri, Apr 6, 2018 at 12:56 AM, Arnd Bergmann <arnd@arndb.de> wrote:
> On Fri, Apr 6, 2018 at 9:25 AM, Tobias Regnery <tobias.regnery@gmail.com> wrote:
>> Commit 58eb5b670747 ("pstore: fix crypto dependencies") fixed up the crypto
>> dependencies but missed the case when no compression is selected.
>>
>> With CONFIG_PSTORE=y, CONFIG_PSTORE_COMPRESS=n  and CONFIG_CRYPTO=m we see
>> the following link error:
>>
>> fs/pstore/platform.o: In function `pstore_register':
>> (.text+0x1b1): undefined reference to `crypto_has_alg'
>> (.text+0x205): undefined reference to `crypto_alloc_base'
>> fs/pstore/platform.o: In function `pstore_unregister':
>> (.text+0x3b0): undefined reference to `crypto_destroy_tfm'
>>
>> Fix this by checking at compile-time if CONFIG_PSTORE_COMPRESS is enabled.
>>
>> Fixes: 58eb5b670747 ("pstore: fix crypto dependencies")
>> Signed-off-by: Tobias Regnery <tobias.regnery@gmail.com>
>> ---
>> v2: check the config at compile-time rather than change the
>>     kconfig-dependency as suggested by Arnd.
>
> Thanks!
>
> Acked-by: Arnd Bergmann <arnd@arndb.de>

Thanks! I'll apply this.

-Kees

-- 
Kees Cook
Pixel Security