On Thu, Feb 5, 2026 at 7:45 PM Richard Henderson <
richard.henderson@linaro.org> wrote:
> On 2/6/26 03:26, Warner Losh wrote:
> > From: Stacey Son <sson@FreeBSD.org>
> >
> > Add target_to_host_msqid_ds() to convert target struct msqid_ds to host
> > format for msgctl(2) IPC_SET operations. Uses memset to zero the struct
> > rather than directly accessing kernel-only members. Handles FreeBSD
> > 64-bit time_t except on i386.
> >
> > Signed-off-by: Stacey Son <sson@FreeBSD.org>
> > Signed-off-by: Brooks Davis <brooks@one-eyed-alien.net>
> > Signed-off-by: Sean Bruno <sbruno@FreeBSD.org>
> > Signed-off-by: Mikael Urankar <mikael.urankar@gmail.com>
> > Signed-off-by: Warner Losh <imp@bsdimp.com>
> > ---
> > bsd-user/bsd-misc.c | 33 +++++++++++++++++++++++++++++++++
> > 1 file changed, 33 insertions(+)
> >
> > diff --git a/bsd-user/bsd-misc.c b/bsd-user/bsd-misc.c
> > index f35f682aa4..e7031c5264 100644
> > --- a/bsd-user/bsd-misc.c
> > +++ b/bsd-user/bsd-misc.c
> > @@ -154,3 +154,36 @@ abi_long host_to_target_semid_ds(abi_ulong
> target_addr,
> >
> > return 0;
> > }
> > +
> > +abi_long target_to_host_msqid_ds(struct msqid_ds *host_md,
> > + abi_ulong target_addr)
> > +{
> > + struct target_msqid_ds *target_md;
> > +
> > + if (!lock_user_struct(VERIFY_READ, target_md, target_addr, 1)) {
> > + return -TARGET_EFAULT;
> > + }
> > +
> > + memset(host_md, 0, sizeof(struct msqid_ds));
> > + target_to_host_ipc_perm__locked(&host_md->msg_perm,
> > + &target_md->msg_perm);
> > +
> > + /* msg_first and msg_last are not used by IPC_SET/IPC_STAT in
> kernel. */
> > + host_md->msg_cbytes = tswapal(target_md->msg_cbytes);
> > + host_md->msg_qnum = tswapal(target_md->msg_qnum);
> > + host_md->msg_qbytes = tswapal(target_md->msg_qbytes);
> > + host_md->msg_lspid = tswapal(target_md->msg_lspid);
> > + host_md->msg_lrpid = tswapal(target_md->msg_lrpid);
> > +#if defined(TARGET_I386)
> > + host_md->msg_stime = tswap32(target_md->msg_stime);
> > + host_md->msg_rtime = tswap32(target_md->msg_rtime);
> > + host_md->msg_ctime = tswap32(target_md->msg_ctime);
> > +#else
> > + host_md->msg_stime = tswap64(target_md->msg_stime);
> > + host_md->msg_rtime = tswap64(target_md->msg_rtime);
> > + host_md->msg_ctime = tswap64(target_md->msg_ctime);
> > +#endif
> > + unlock_user_struct(target_md, target_addr, 0);
> > +
> > + return 0;
> > +}
> >
>
> Use __get_user and you won't need the ifdef, since the size of the type is
> then
> automatically handled.
>
Agreed.
Warner