| Message ID | 1468083696-15283-1-git-send-email-arvind.yadav.cs@gmail.com (mailing list archive) |
|---|---|
| State | Rejected |
| Delegated to: | Kalle Valo |
| Headers | show |
Arvind Yadav <arvind.yadav.cs@gmail.com> wrote: > IS_ERR_VALUE() assumes that its parameter is an unsigned long. > It can not be used to check if an 'unsigned int' reflects an error. > As they pass an 'unsigned int' into a function that takes an > 'unsigned long' argument. This happens to work because the type > is sign-extended on 64-bit architectures before it gets converted > into an unsigned type. > > However, anything that passes an 'unsigned short' or 'unsigned int' > argument into IS_ERR_VALUE() is guaranteed to be broken, as are > 8-bit integers and types that are wider than 'unsigned long'. > > It would be nice to any users that are not passing 'unsigned int' > arguments. > > Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com> This touches include/linux/err.h and I'm not very enthusiastic to change anything in include directory without wider support. I recommend first to just fix bcma. And separately you can try to improve linux/err.h via some more approariate tree, not via wireless trees.
diff --git a/drivers/bcma/scan.c b/drivers/bcma/scan.c index 4a2d1b2..3bc77eb 100644 --- a/drivers/bcma/scan.c +++ b/drivers/bcma/scan.c @@ -272,7 +272,6 @@ static struct bcma_device *bcma_find_core_reverse(struct bcma_bus *bus, u16 core return NULL; } -#define IS_ERR_VALUE_U32(x) ((x) >= (u32)-MAX_ERRNO) static int bcma_get_next_core(struct bcma_bus *bus, u32 __iomem **eromptr, struct bcma_device_id *match, int core_num, diff --git a/include/linux/err.h b/include/linux/err.h index 1e35588..e05a63d 100644 --- a/include/linux/err.h +++ b/include/linux/err.h @@ -20,6 +20,8 @@ #define IS_ERR_VALUE(x) unlikely((unsigned long)(void *)(x) >= (unsigned long)-MAX_ERRNO) +#define IS_ERR_VALUE_U32(x) unlikely((unsigned int)(x) >= (unsigned int)-MAX_ERRNO) + static inline void * __must_check ERR_PTR(long error) { return (void *) error;
IS_ERR_VALUE() assumes that its parameter is an unsigned long. It can not be used to check if an 'unsigned int' reflects an error. As they pass an 'unsigned int' into a function that takes an 'unsigned long' argument. This happens to work because the type is sign-extended on 64-bit architectures before it gets converted into an unsigned type. However, anything that passes an 'unsigned short' or 'unsigned int' argument into IS_ERR_VALUE() is guaranteed to be broken, as are 8-bit integers and types that are wider than 'unsigned long'. It would be nice to any users that are not passing 'unsigned int' arguments. Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com> --- drivers/bcma/scan.c | 1 - include/linux/err.h | 2 ++ 2 files changed, 2 insertions(+), 1 deletion(-)