| Message ID | 20210222151231.22572-14-romain.perier@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Manual replacement of all strlcpy in favor of strscpy | expand |
On Mon, Feb 22, 2021 at 04:12:24PM +0100, Romain Perier wrote: > The strlcpy() reads the entire source buffer first, it is dangerous if > the source buffer lenght is unbounded or possibility non NULL-terminated. > It can lead to linear read overflows, crashes, etc... > > As recommended in the deprecated interfaces [1], it should be replaced > by strscpy. > > This commit replaces all calls to strlcpy that handle the return values > by the corresponding strscpy calls with new handling of the return > values (as it is quite different between the two functions). > > [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy > > Signed-off-by: Romain Perier <romain.perier@gmail.com> > --- > drivers/s390/scsi/zfcp_fc.c | 8 +++++--- > 1 file changed, 5 insertions(+), 3 deletions(-) > > diff --git a/drivers/s390/scsi/zfcp_fc.c b/drivers/s390/scsi/zfcp_fc.c > index d24cafe02708..8a65241011b9 100644 > --- a/drivers/s390/scsi/zfcp_fc.c > +++ b/drivers/s390/scsi/zfcp_fc.c > @@ -877,14 +877,16 @@ static void zfcp_fc_rspn(struct zfcp_adapter *adapter, > struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els; > struct zfcp_fc_rspn_req *rspn_req = &fc_req->u.rspn.req; > struct fc_ct_hdr *rspn_rsp = &fc_req->u.rspn.rsp; > - int ret, len; > + int ret; > + ssize_t len; > > zfcp_fc_ct_ns_init(&rspn_req->ct_hdr, FC_NS_RSPN_ID, > FC_SYMBOLIC_NAME_SIZE); > hton24(rspn_req->rspn.fr_fid.fp_fid, fc_host_port_id(shost)); > - len = strlcpy(rspn_req->rspn.fr_name, fc_host_symbolic_name(shost), > + len = strscpy(rspn_req->rspn.fr_name, fc_host_symbolic_name(shost), > FC_SYMBOLIC_NAME_SIZE); > - rspn_req->rspn.fr_name_len = len; > + if (len != -E2BIG) > + rspn_req->rspn.fr_name_len = len; That is a bug. Leaving `rspn.fr_name_len` uninitialized defeats the purpose of sending a RSPN. How about: if (len == -E2BIG) rspn_req->rspn.fr_name_len = FC_SYMBOLIC_NAME_SIZE - 1; else rspn_req->rspn.fr_name_len = len; > > sg_init_one(&fc_req->sg_req, rspn_req, sizeof(*rspn_req)); > sg_init_one(&fc_req->sg_rsp, rspn_rsp, sizeof(*rspn_rsp)); >
diff --git a/drivers/s390/scsi/zfcp_fc.c b/drivers/s390/scsi/zfcp_fc.c index d24cafe02708..8a65241011b9 100644 --- a/drivers/s390/scsi/zfcp_fc.c +++ b/drivers/s390/scsi/zfcp_fc.c @@ -877,14 +877,16 @@ static void zfcp_fc_rspn(struct zfcp_adapter *adapter, struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els; struct zfcp_fc_rspn_req *rspn_req = &fc_req->u.rspn.req; struct fc_ct_hdr *rspn_rsp = &fc_req->u.rspn.rsp; - int ret, len; + int ret; + ssize_t len; zfcp_fc_ct_ns_init(&rspn_req->ct_hdr, FC_NS_RSPN_ID, FC_SYMBOLIC_NAME_SIZE); hton24(rspn_req->rspn.fr_fid.fp_fid, fc_host_port_id(shost)); - len = strlcpy(rspn_req->rspn.fr_name, fc_host_symbolic_name(shost), + len = strscpy(rspn_req->rspn.fr_name, fc_host_symbolic_name(shost), FC_SYMBOLIC_NAME_SIZE); - rspn_req->rspn.fr_name_len = len; + if (len != -E2BIG) + rspn_req->rspn.fr_name_len = len; sg_init_one(&fc_req->sg_req, rspn_req, sizeof(*rspn_req)); sg_init_one(&fc_req->sg_rsp, rspn_rsp, sizeof(*rspn_rsp));
The strlcpy() reads the entire source buffer first, it is dangerous if the source buffer lenght is unbounded or possibility non NULL-terminated. It can lead to linear read overflows, crashes, etc... As recommended in the deprecated interfaces [1], it should be replaced by strscpy. This commit replaces all calls to strlcpy that handle the return values by the corresponding strscpy calls with new handling of the return values (as it is quite different between the two functions). [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy Signed-off-by: Romain Perier <romain.perier@gmail.com> --- drivers/s390/scsi/zfcp_fc.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)