Messages in this thread | | | Date | Fri, 20 Aug 2010 22:15:41 -0400 (EDT) | From | Miloslav Trmac <> | Subject | Re: [PATCH 06/19] Add ioctl() argument and attribute handling utils |
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----- "Stefan Richter" <stefanr@s5r6.in-berlin.de> wrote: > Miloslav Trmač wrote: > > --- /dev/null > > +++ b/crypto/userspace/utils.c > [...] > > +#ifdef CONFIG_COMPAT > > +/* max() is too clever for compile-time constants */ > > +#define CONST_MAX(A, B) ((A) > (B) ? (A) : (B)) > > + > > +#define MAX_SESSION_INPUT_DATA_SIZE \ > > + (CONST_MAX(sizeof(struct ncr_session_input_data), \ > > + sizeof(struct compat_ncr_session_input_data))) > > +#define MAX_SESSION_OUTPUT_BUFFER_SIZE \ > > + (CONST_MAX(sizeof(struct ncr_session_output_buffer), \ > > + sizeof(struct compat_ncr_session_output_buffer))) > > + > > +#else /* !CONFIG_COMPAT */ > > + > > +#define MAX_SESSION_INPUT_DATA_SIZE (sizeof(struct ncr_session_input_data)) > > +#define MAX_SESSION_OUTPUT_BUFFER_SIZE \ > > + (sizeof(struct ncr_session_output_buffer)) > > + > > +#endif /* !CONFIG_COMPAT */ > > struct compat_xyz cannot be bigger than struct xyz, can it? Perhaps not, but the code has been written and it's easier to keep it than to speculate :) It also helps document the fact that the data format depends on properties of the userspace. Mirek -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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