2021-03-22 12:01:07

by Arnd Bergmann

Subject: [PATCH net-next] ipv6: fix clang Wformat warning

From: Arnd Bergmann <[email protected]>

When building with 'make W=1', clang warns about a mismatched
format string:

net/ipv6/ah6.c:710:4: error: format specifies type 'unsigned short' but the argument has type 'int' [-Werror,-Wformat]
aalg_desc->uinfo.auth.icv_fullbits/8);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/printk.h:375:34: note: expanded from macro 'pr_info'
printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
~~~ ^~~~~~~~~~~
net/ipv6/esp6.c:1153:5: error: format specifies type 'unsigned short' but the argument has type 'int' [-Werror,-Wformat]
aalg_desc->uinfo.auth.icv_fullbits / 8);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/printk.h:375:34: note: expanded from macro 'pr_info'
printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
~~~ ^~~~~~~~~~~

Here, the result of dividing a 16-bit number by a 32-bit number
produces a 32-bit result, which is printed as a 16-bit integer.

Change the %hu format to the normal %u, which has the same effect
but avoids the warning.

Signed-off-by: Arnd Bergmann <[email protected]>
---
net/ipv6/ah6.c | 2 +-
net/ipv6/esp6.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/ipv6/ah6.c b/net/ipv6/ah6.c
index 440080da805b..01c638f5d8b8 100644
--- a/net/ipv6/ah6.c
+++ b/net/ipv6/ah6.c
@@ -705,7 +705,7 @@ static int ah6_init_state(struct xfrm_state *x)

if (aalg_desc->uinfo.auth.icv_fullbits/8 !=
crypto_ahash_digestsize(ahash)) {
- pr_info("AH: %s digestsize %u != %hu\n",
+ pr_info("AH: %s digestsize %u != %u\n",
x->aalg->alg_name, crypto_ahash_digestsize(ahash),
aalg_desc->uinfo.auth.icv_fullbits/8);
goto error;
diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c
index 153ad103ba74..831a588b04a2 100644
--- a/net/ipv6/esp6.c
+++ b/net/ipv6/esp6.c
@@ -1147,7 +1147,7 @@ static int esp_init_authenc(struct xfrm_state *x)
err = -EINVAL;
if (aalg_desc->uinfo.auth.icv_fullbits / 8 !=
crypto_aead_authsize(aead)) {
- pr_info("ESP: %s digestsize %u != %hu\n",
+ pr_info("ESP: %s digestsize %u != %u\n",
x->aalg->alg_name,
crypto_aead_authsize(aead),
aalg_desc->uinfo.auth.icv_fullbits / 8);
--
2.29.2

2021-03-26 10:30:58

by Steffen Klassert

Subject: Re: [PATCH net-next] ipv6: fix clang Wformat warning

On Mon, Mar 22, 2021 at 12:56:49PM +0100, Arnd Bergmann wrote:
> From: Arnd Bergmann <[email protected]>
>
> When building with 'make W=1', clang warns about a mismatched
> format string:
>
> net/ipv6/ah6.c:710:4: error: format specifies type 'unsigned short' but the argument has type 'int' [-Werror,-Wformat]
> aalg_desc->uinfo.auth.icv_fullbits/8);
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/printk.h:375:34: note: expanded from macro 'pr_info'
> printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
> ~~~ ^~~~~~~~~~~
> net/ipv6/esp6.c:1153:5: error: format specifies type 'unsigned short' but the argument has type 'int' [-Werror,-Wformat]
> aalg_desc->uinfo.auth.icv_fullbits / 8);
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/printk.h:375:34: note: expanded from macro 'pr_info'
> printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
> ~~~ ^~~~~~~~~~~
>
> Here, the result of dividing a 16-bit number by a 32-bit number
> produces a 32-bit result, which is printed as a 16-bit integer.
>
> Change the %hu format to the normal %u, which has the same effect
> but avoids the warning.
>
> Signed-off-by: Arnd Bergmann <[email protected]>

Applied to ipsec-next, thanks!