Hi folks, I'm currently working on this task: http://kernelnewbies.org/KernelJanitors/Todo/ReturnCodes I think this task can be partly done with coccinelle. The most often cases of invalid handling is no handling :) I am not guru of coccinelle, but I think it is very useful here. So, I've written basic script of finding common errors, but it is not ideal. Some trivial "metamorphisms" can be added, like this: if (!x) ... is equivalent in our case to if (unlikely(!x)) ... likely(), unlikely(), WARN(), some_driver_defined_assert(), etc. Currently script finds ~400 patterns in linux-next, some of them are false positive. Even if there were no false positives it is a rather long process :) So, I'm calling for help in raking this mess and improving the script. // These are checks for allocation function, only comparation with 0 is ok @@ identifier x; identifier f ~= "request_region$\|kmalloc$\|vmalloc$\|pci_map_.*$\|get_free_pages$\|get_free_page$\|ioremap$\|create_proc_.*$"; statement S1, S2; @@ \( *x = f(...); ... when != if (x) S1 else S2 when != if (x == 0) S1 else S2 when != if (x == NULL) S1 else S2 when != if (x != 0) S1 else S2 when != if (x != NULL) S1 else S2 when != if (!x) S1 else S2 when != return x; \| *f(...); \) // These are checks for functions that return 0 on success and smth <0 on error // Result can be checked as (ret == 0), (ret < 0) and as (ret >= 0) @@ identifier x; identifier f ~= "request_irq$\|register_netdev$\|misc_register$\|scsi_register$\|put_user$\|get_user$\|kernel_thread$"; statement S1, S2; @@ \( *x = f(...); ... when != if (x < 0) S1 else S2 when != if (x >= 0) S1 else S2 when != if (x != 0) S1 else S2 when != if (!x) S1 else S2 when != if (x == 0) S1 else S2 when != return x; \| *f(...); \) // These are function returning 0 on success and positive (!!!) result on error // Result can be checked as (ret == 0), (ret > 0) // @@ identifier x; identifier f ~= "copy_to_user$\|copy_from_user$"; statement S1, S2; @@ \( *x = f(...); ... when != if (x) S1 else S2 when != if (!x) S1 else S2 when != if (x > 0) S1 else S2 when != return x; \| *f(...); \) Thanks, Vasiliy. -- To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
