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I can implement something like that in Smatch. > I'll run the attached check over the kernel and see what it turns up. I've only used sparse I think (make C=3D1) I need to lookup how to use Smat= ch. > It says that it's only checking assignments but the trick is that > Smatch creates fake assignments in the background for passing parameters > or returning. So "return a ? uint_val : -ENOMEM;" will trigger an error > message. Sounds good. > If there are too many false positives when I test this tonight, then I > may make is_suspicious_int() more strict. If that's any help, the exact bug where we hit this is currently in fs/cifs/file.c in collect_uncached_write_data(), this line: ctx->rc =3D (rc =3D=3D 0) ? ctx->total_len : rc; Hopefully it shows up in your tests. =20 Cheers, --=20 Aur=C3=A9lien Aptel / SUSE Labs Samba Team GPG: 1839 CB5F 9F5B FB9B AA97 8C99 03C8 A49B 521B D5D3 SUSE Software Solutions Germany GmbH, Maxfeldstr. 5, 90409 N=C3=BCrnberg, D= E GF: Felix Imend=C3=B6rffer, Mary Higgins, Sri Rasiah HRB 247165 (AG M=C3=BC= nchen)