strncpy() is deprecated [1] and as such we should use different apis to
copy string data.
We can see that ct is NUL-initialized with fc_ct_hdr_fill:
| ct = fc_ct_hdr_fill(fp, op, sizeof(struct fc_ns_rspn) + len,
...
In fc_ct_hdr_fill():
| memset(ct, 0, ct_plen);
We also calculate the length of the source string:
| len = strnlen(fc_host_symbolic_name(lport->host), 255);
then this argument is used in strncpy(), which is bad because the
pattern of (dest, src, strlen(src)) usually leaves the destination
buffer without NUL-termination. However, this seems to be correct in
this instance since fr_name is part of a seq_buf-like structure
monitoring the length:
| struct fc_ns_rspn {
| struct fc_ns_fid fr_fid; /* port ID object */
| __u8 fr_name_len;
| char fr_name[];
| } __attribute__((__packed__));
So, this is really just a byte copy into a length-bounded string. Let's
use memcpy() and mark the buffers as __nonstring.
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://github.com/KSPP/linux/issues/90
Cc: [email protected]
Signed-off-by: Justin Stitt <[email protected]>
---
Note: build-tested only.
Found with: $ rg "strncpy\("
---
drivers/scsi/libfc/fc_encode.h | 8 ++++----
include/uapi/scsi/fc/fc_ns.h | 6 +++---
2 files changed, 7 insertions(+), 7 deletions(-)
diff --git a/drivers/scsi/libfc/fc_encode.h b/drivers/scsi/libfc/fc_encode.h
index 7dcac3b6baa7..ba8cc4ee650c 100644
--- a/drivers/scsi/libfc/fc_encode.h
+++ b/drivers/scsi/libfc/fc_encode.h
@@ -140,8 +140,8 @@ static inline int fc_ct_ns_fill(struct fc_lport *lport,
ct = fc_ct_hdr_fill(fp, op, sizeof(struct fc_ns_rspn) + len,
FC_FST_DIR, FC_NS_SUBTYPE);
hton24(ct->payload.spn.fr_fid.fp_fid, lport->port_id);
- strncpy(ct->payload.spn.fr_name,
- fc_host_symbolic_name(lport->host), len);
+ memcpy(ct->payload.spn.fr_name,
+ fc_host_symbolic_name(lport->host), len);
ct->payload.spn.fr_name_len = len;
break;
@@ -150,8 +150,8 @@ static inline int fc_ct_ns_fill(struct fc_lport *lport,
ct = fc_ct_hdr_fill(fp, op, sizeof(struct fc_ns_rsnn) + len,
FC_FST_DIR, FC_NS_SUBTYPE);
put_unaligned_be64(lport->wwnn, &ct->payload.snn.fr_wwn);
- strncpy(ct->payload.snn.fr_name,
- fc_host_symbolic_name(lport->host), len);
+ memcpy(ct->payload.snn.fr_name,
+ fc_host_symbolic_name(lport->host), len);
ct->payload.snn.fr_name_len = len;
break;
diff --git a/include/uapi/scsi/fc/fc_ns.h b/include/uapi/scsi/fc/fc_ns.h
index 4cf0a40a099a..8a6f6c6b5213 100644
--- a/include/uapi/scsi/fc/fc_ns.h
+++ b/include/uapi/scsi/fc/fc_ns.h
@@ -145,7 +145,7 @@ struct fc_gid_pn_resp {
*/
struct fc_gspn_resp {
__u8 fp_name_len;
- char fp_name[];
+ char fp_name[] __nonstring;
};
/*
@@ -171,7 +171,7 @@ struct fc_ns_rn_id {
struct fc_ns_rsnn {
__be64 fr_wwn; /* node name */
__u8 fr_name_len;
- char fr_name[];
+ char fr_name[] __nonstring;
} __attribute__((__packed__));
/*
@@ -180,7 +180,7 @@ struct fc_ns_rsnn {
struct fc_ns_rspn {
struct fc_ns_fid fr_fid; /* port ID object */
__u8 fr_name_len;
- char fr_name[];
+ char fr_name[] __nonstring;
} __attribute__((__packed__));
/*
---
base-commit: ffc253263a1375a65fa6c9f62a893e9767fbebfa
change-id: 20231030-strncpy-drivers-scsi-libfc-fc_encode-h-5ad629f6de9c
Best regards,
--
Justin Stitt <[email protected]>
Hi Justin,
kernel test robot noticed the following build warnings:
[auto build test WARNING on ffc253263a1375a65fa6c9f62a893e9767fbebfa]
url: https://github.com/intel-lab-lkp/linux/commits/Justin-Stitt/scsi-libfc-replace-deprecated-strncpy-with-memcpy/20231031-063815
base: ffc253263a1375a65fa6c9f62a893e9767fbebfa
patch link: https://lore.kernel.org/r/20231030-strncpy-drivers-scsi-libfc-fc_encode-h-v1-1-c08c2be6befa%40google.com
patch subject: [PATCH] scsi: libfc: replace deprecated strncpy with memcpy
config: s390-defconfig (https://download.01.org/0day-ci/archive/20231102/[email protected]/config)
compiler: s390-linux-gcc (GCC) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231102/[email protected]/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
All warnings (new ones prefixed by >>):
In function 'zfcp_fc_gspn',
inlined from 'zfcp_fc_sym_name_update' at drivers/s390/scsi/zfcp_fc.c:951:8:
>> drivers/s390/scsi/zfcp_fc.c:877:15: warning: 'strstr' argument 1 declared attribute 'nonstring' [-Wstringop-overread]
877 | !(strstr(gspn_rsp->gspn.fp_name, devno)))
| ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from include/scsi/libfc.h:21,
from drivers/s390/scsi/zfcp_fc.c:19:
include/uapi/scsi/fc/fc_ns.h: In function 'zfcp_fc_sym_name_update':
include/uapi/scsi/fc/fc_ns.h:148:17: note: argument 'fp_name' declared here
148 | char fp_name[] __nonstring;
| ^~~~~~~
vim +877 drivers/s390/scsi/zfcp_fc.c
cc8c282963bd25 Swen Schillig 2008-06-10 844
038d9446a9e601 Christof Schmitt 2011-02-22 845 static int zfcp_fc_gspn(struct zfcp_adapter *adapter,
038d9446a9e601 Christof Schmitt 2011-02-22 846 struct zfcp_fc_req *fc_req)
038d9446a9e601 Christof Schmitt 2011-02-22 847 {
038d9446a9e601 Christof Schmitt 2011-02-22 848 DECLARE_COMPLETION_ONSTACK(completion);
038d9446a9e601 Christof Schmitt 2011-02-22 849 char devno[] = "DEVNO:";
038d9446a9e601 Christof Schmitt 2011-02-22 850 struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
038d9446a9e601 Christof Schmitt 2011-02-22 851 struct zfcp_fc_gspn_req *gspn_req = &fc_req->u.gspn.req;
038d9446a9e601 Christof Schmitt 2011-02-22 852 struct zfcp_fc_gspn_rsp *gspn_rsp = &fc_req->u.gspn.rsp;
038d9446a9e601 Christof Schmitt 2011-02-22 853 int ret;
038d9446a9e601 Christof Schmitt 2011-02-22 854
038d9446a9e601 Christof Schmitt 2011-02-22 855 zfcp_fc_ct_ns_init(&gspn_req->ct_hdr, FC_NS_GSPN_ID,
038d9446a9e601 Christof Schmitt 2011-02-22 856 FC_SYMBOLIC_NAME_SIZE);
038d9446a9e601 Christof Schmitt 2011-02-22 857 hton24(gspn_req->gspn.fp_fid, fc_host_port_id(adapter->scsi_host));
038d9446a9e601 Christof Schmitt 2011-02-22 858
038d9446a9e601 Christof Schmitt 2011-02-22 859 sg_init_one(&fc_req->sg_req, gspn_req, sizeof(*gspn_req));
038d9446a9e601 Christof Schmitt 2011-02-22 860 sg_init_one(&fc_req->sg_rsp, gspn_rsp, sizeof(*gspn_rsp));
038d9446a9e601 Christof Schmitt 2011-02-22 861
038d9446a9e601 Christof Schmitt 2011-02-22 862 ct_els->handler = zfcp_fc_complete;
038d9446a9e601 Christof Schmitt 2011-02-22 863 ct_els->handler_data = &completion;
038d9446a9e601 Christof Schmitt 2011-02-22 864 ct_els->req = &fc_req->sg_req;
038d9446a9e601 Christof Schmitt 2011-02-22 865 ct_els->resp = &fc_req->sg_rsp;
038d9446a9e601 Christof Schmitt 2011-02-22 866
038d9446a9e601 Christof Schmitt 2011-02-22 867 ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
038d9446a9e601 Christof Schmitt 2011-02-22 868 ZFCP_FC_CTELS_TMO);
038d9446a9e601 Christof Schmitt 2011-02-22 869 if (ret)
038d9446a9e601 Christof Schmitt 2011-02-22 870 return ret;
038d9446a9e601 Christof Schmitt 2011-02-22 871
038d9446a9e601 Christof Schmitt 2011-02-22 872 wait_for_completion(&completion);
038d9446a9e601 Christof Schmitt 2011-02-22 873 if (ct_els->status)
038d9446a9e601 Christof Schmitt 2011-02-22 874 return ct_els->status;
038d9446a9e601 Christof Schmitt 2011-02-22 875
038d9446a9e601 Christof Schmitt 2011-02-22 876 if (fc_host_port_type(adapter->scsi_host) == FC_PORTTYPE_NPIV &&
038d9446a9e601 Christof Schmitt 2011-02-22 @877 !(strstr(gspn_rsp->gspn.fp_name, devno)))
038d9446a9e601 Christof Schmitt 2011-02-22 878 snprintf(fc_host_symbolic_name(adapter->scsi_host),
038d9446a9e601 Christof Schmitt 2011-02-22 879 FC_SYMBOLIC_NAME_SIZE, "%s%s %s NAME: %s",
038d9446a9e601 Christof Schmitt 2011-02-22 880 gspn_rsp->gspn.fp_name, devno,
038d9446a9e601 Christof Schmitt 2011-02-22 881 dev_name(&adapter->ccw_device->dev),
038d9446a9e601 Christof Schmitt 2011-02-22 882 init_utsname()->nodename);
038d9446a9e601 Christof Schmitt 2011-02-22 883 else
820109fb11f24b Wolfram Sang 2022-08-18 884 strscpy(fc_host_symbolic_name(adapter->scsi_host),
038d9446a9e601 Christof Schmitt 2011-02-22 885 gspn_rsp->gspn.fp_name, FC_SYMBOLIC_NAME_SIZE);
038d9446a9e601 Christof Schmitt 2011-02-22 886
038d9446a9e601 Christof Schmitt 2011-02-22 887 return 0;
038d9446a9e601 Christof Schmitt 2011-02-22 888 }
038d9446a9e601 Christof Schmitt 2011-02-22 889
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Hi Justin,
kernel test robot noticed the following build errors:
[auto build test ERROR on ffc253263a1375a65fa6c9f62a893e9767fbebfa]
url: https://github.com/intel-lab-lkp/linux/commits/Justin-Stitt/scsi-libfc-replace-deprecated-strncpy-with-memcpy/20231031-063815
base: ffc253263a1375a65fa6c9f62a893e9767fbebfa
patch link: https://lore.kernel.org/r/20231030-strncpy-drivers-scsi-libfc-fc_encode-h-v1-1-c08c2be6befa%40google.com
patch subject: [PATCH] scsi: libfc: replace deprecated strncpy with memcpy
config: i386-randconfig-141-20231102 (https://download.01.org/0day-ci/archive/20231103/[email protected]/config)
compiler: gcc-7 (Ubuntu 7.5.0-6ubuntu2) 7.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231103/[email protected]/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
All errors (new ones prefixed by >>):
In file included from <command-line>:32:0:
>> ./usr/include/scsi/fc/fc_ns.h:148:17: error: expected ':', ',', ';', '}' or '__attribute__' before '__nonstring'
char fp_name[] __nonstring;
^~~~~~~~~~~
./usr/include/scsi/fc/fc_ns.h:174:18: error: expected ':', ',', ';', '}' or '__attribute__' before '__nonstring'
char fr_name[] __nonstring;
^~~~~~~~~~~
./usr/include/scsi/fc/fc_ns.h:183:18: error: expected ':', ',', ';', '}' or '__attribute__' before '__nonstring'
char fr_name[] __nonstring;
^~~~~~~~~~~
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki