| Message ID | 20220709003704.646568-1-justinstitt@google.com (mailing list archive) |
|---|---|
| State | Awaiting Upstream |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [v2] net: ipv4: fix clang -Wformat warnings | expand |
On Fri, Jul 08, 2022 at 05:37:04PM -0700, Justin Stitt wrote: > When building with Clang we encounter these warnings: > | net/ipv4/ah4.c:513:4: error: format specifies type 'unsigned short' but > | the argument has type 'int' [-Werror,-Wformat] > | aalg_desc->uinfo.auth.icv_fullbits / 8); > - > | net/ipv4/esp4.c:1114:5: error: format specifies type 'unsigned short' > | but the argument has type 'int' [-Werror,-Wformat] > | aalg_desc->uinfo.auth.icv_fullbits / 8); > > `aalg_desc->uinfo.auth.icv_fullbits` is a u16 but due to default > argument promotion becomes an int. > > Variadic functions (printf-like) undergo default argument promotion. > Documentation/core-api/printk-formats.rst specifically recommends using > the promoted-to-type's format flag. > > As per C11 6.3.1.1: > (https://www.open-std.org/jtc1/sc22/wg14/www/docs/n1548.pdf) `If an int > can represent all values of the original type ..., the value is > converted to an int; otherwise, it is converted to an unsigned int. > These are called the integer promotions.` Thus it makes sense to change > %hu to %d not only to follow this standard but to suppress the warning > as well. > > Link: https://github.com/ClangBuiltLinux/linux/issues/378 > Signed-off-by: Justin Stitt <justinstitt@google.com> > Suggested-by: Joe Perches <joe@perches.com> > Suggested-by: Nathan Chancellor <nathan@kernel.org> > Suggested-by: Nick Desaulniers <ndesaulniers@google.com> Applied to the ipsec tree, thanks a lot!
diff from v1 -> v2: * packaged two related patches together: (Suggested by Nick) - https://lore.kernel.org/all/20220707181532.762452-1-justinstitt@google.com/ - https://lore.kernel.org/all/20220707173040.704116-1-justinstitt@google.com/ * use Joe's suggestion regarding `%u` over `%d`. net/ipv4/ah4.c | 2 +- net/ipv4/esp4.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/net/ipv4/ah4.c b/net/ipv4/ah4.c index 6eea1e9e998d..f8ad04470d3a 100644 --- a/net/ipv4/ah4.c +++ b/net/ipv4/ah4.c @@ -507,7 +507,7 @@ static int ah_init_state(struct xfrm_state *x) if (aalg_desc->uinfo.auth.icv_fullbits/8 != crypto_ahash_digestsize(ahash)) { - pr_info("%s: %s digestsize %u != %hu\n", + pr_info("%s: %s digestsize %u != %u\n", __func__, x->aalg->alg_name, crypto_ahash_digestsize(ahash), aalg_desc->uinfo.auth.icv_fullbits / 8); diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c index b21238df3301..b694f352ce7a 100644 --- a/net/ipv4/esp4.c +++ b/net/ipv4/esp4.c @@ -1108,7 +1108,7 @@ 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);
When building with Clang we encounter these warnings: | net/ipv4/ah4.c:513:4: error: format specifies type 'unsigned short' but | the argument has type 'int' [-Werror,-Wformat] | aalg_desc->uinfo.auth.icv_fullbits / 8); - | net/ipv4/esp4.c:1114:5: error: format specifies type 'unsigned short' | but the argument has type 'int' [-Werror,-Wformat] | aalg_desc->uinfo.auth.icv_fullbits / 8); `aalg_desc->uinfo.auth.icv_fullbits` is a u16 but due to default argument promotion becomes an int. Variadic functions (printf-like) undergo default argument promotion. Documentation/core-api/printk-formats.rst specifically recommends using the promoted-to-type's format flag. As per C11 6.3.1.1: (https://www.open-std.org/jtc1/sc22/wg14/www/docs/n1548.pdf) `If an int can represent all values of the original type ..., the value is converted to an int; otherwise, it is converted to an unsigned int. These are called the integer promotions.` Thus it makes sense to change %hu to %d not only to follow this standard but to suppress the warning as well. Link: https://github.com/ClangBuiltLinux/linux/issues/378 Signed-off-by: Justin Stitt <justinstitt@google.com> Suggested-by: Joe Perches <joe@perches.com> Suggested-by: Nathan Chancellor <nathan@kernel.org> Suggested-by: Nick Desaulniers <ndesaulniers@google.com> ---