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I still think it's a reasonable change to use the ssize_t since the= rc is a ssize_t and the outbound syscall path is also a ssize_t. Best case= scenario is a segfault in userspace (made things easier to track down), bu= t will likely wind up with memory corruption otherwise. Looking at this more I found that commit 97adda8b3ab7 fixed a very similar issue: - ctx->rc =3D (rc =3D=3D 0) ? ctx->total_len : rc; + ctx->rc =3D (rc =3D=3D 0) ? (ssize_t)ctx->total_len : rc; I think the logic is that compiler sees the "then" part as unsigned and so casts the "else" part to unsigned as well. In any case I think the change is good. We could change rc type in the read path as well. Reviewed-by: Aurelien Aptel 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)