This series contains multiple replacements of strncpy throughout the
scsi subsystem.
strncpy() is deprecated for use on NUL-terminated destination strings
[1] and as such we should prefer more robust and less ambiguous string
interfaces. The details of each replacement will be in their respective
patch.
---
Changes in v3:
- update trailers (thanks Kees)
- Link to v2: https://lore.kernel.org/r/20240228-strncpy-drivers-scsi-mpi3mr-mpi3mr_fw-c-v2-0-dacebd3fcfa0@google.com
Changes in v2:
- for (1/7): change strscpy to simple const char* assignments
- Link to v1: https://lore.kernel.org/r/20240223-strncpy-drivers-scsi-mpi3mr-mpi3mr_fw-c-v1-0-9cd3882f0700@google.com
---
Justin Stitt (7):
scsi: mpi3mr: replace deprecated strncpy with assignments
scsi: mpt3sas: replace deprecated strncpy with strscpy
scsi: qedf: replace deprecated strncpy with strscpy
scsi: qla4xxx: replace deprecated strncpy with strscpy
scsi: devinfo: replace strncpy and manual pad
scsi: smartpqi: replace deprecated strncpy with strscpy
scsi: wd33c93: replace deprecated strncpy with strscpy
drivers/net/ethernet/qlogic/qed/qed_main.c | 2 +-
drivers/scsi/mpi3mr/mpi3mr_fw.c | 10 +++++-----
drivers/scsi/mpt3sas/mpt3sas_base.c | 2 +-
drivers/scsi/mpt3sas/mpt3sas_transport.c | 18 +++++++++---------
drivers/scsi/qedf/qedf_main.c | 2 +-
drivers/scsi/qla4xxx/ql4_mbx.c | 17 ++++++++++++-----
drivers/scsi/qla4xxx/ql4_os.c | 14 +++++++-------
drivers/scsi/scsi_devinfo.c | 18 ++++++++++--------
drivers/scsi/smartpqi/smartpqi_init.c | 5 ++---
drivers/scsi/wd33c93.c | 4 +---
10 files changed, 49 insertions(+), 43 deletions(-)
---
base-commit: 39133352cbed6626956d38ed72012f49b0421e7b
change-id: 20240222-strncpy-drivers-scsi-mpi3mr-mpi3mr_fw-c-1b130d51bdcc
Best regards,
--
Justin Stitt <[email protected]>
Justin,
> This series contains multiple replacements of strncpy throughout the
> scsi subsystem.
I've queued this up for 6.10.
--
Martin K. Petersen Oracle Linux Engineering
We expect slowpath_params.name to be NUL-terminated based on its future
usage with other string APIs:
| static int qed_slowpath_start(struct qed_dev *cdev,
| struct qed_slowpath_params *params)
..
| strscpy(drv_version.name, params->name,
| MCP_DRV_VER_STR_SIZE - 4);
Moreover, NUL-padding is not necessary as the only use for this slowpath
name parameter is to copy into the drv_version.name field.
Also, let's prefer using strscpy(src, dest, sizeof(src)) in two
instances (one of which is outside of the scsi system but it is trivial
and related to this patch).
We can see the drv_version.name size here:
| struct qed_mcp_drv_version {
| u32 version;
| u8 name[MCP_DRV_VER_STR_SIZE - 4];
| };
Reviewed-by: Kees Cook <[email protected]>
Signed-off-by: Justin Stitt <[email protected]>
---
drivers/net/ethernet/qlogic/qed/qed_main.c | 2 +-
drivers/scsi/qedf/qedf_main.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/qlogic/qed/qed_main.c b/drivers/net/ethernet/qlogic/qed/qed_main.c
index c278f8893042..d39e198fe8db 100644
--- a/drivers/net/ethernet/qlogic/qed/qed_main.c
+++ b/drivers/net/ethernet/qlogic/qed/qed_main.c
@@ -1351,7 +1351,7 @@ static int qed_slowpath_start(struct qed_dev *cdev,
(params->drv_rev << 8) |
(params->drv_eng);
strscpy(drv_version.name, params->name,
- MCP_DRV_VER_STR_SIZE - 4);
+ sizeof(drv_version.name));
rc = qed_mcp_send_drv_version(hwfn, hwfn->p_main_ptt,
&drv_version);
if (rc) {
diff --git a/drivers/scsi/qedf/qedf_main.c b/drivers/scsi/qedf/qedf_main.c
index a58353b7b4e8..fd12439cbaab 100644
--- a/drivers/scsi/qedf/qedf_main.c
+++ b/drivers/scsi/qedf/qedf_main.c
@@ -3468,7 +3468,7 @@ static int __qedf_probe(struct pci_dev *pdev, int mode)
slowpath_params.drv_minor = QEDF_DRIVER_MINOR_VER;
slowpath_params.drv_rev = QEDF_DRIVER_REV_VER;
slowpath_params.drv_eng = QEDF_DRIVER_ENG_VER;
- strncpy(slowpath_params.name, "qedf", QED_DRV_VER_STR_SIZE);
+ strscpy(slowpath_params.name, "qedf", sizeof(slowpath_params.name));
rc = qed_ops->common->slowpath_start(qedf->cdev, &slowpath_params);
if (rc) {
QEDF_ERR(&(qedf->dbg_ctx), "Cannot start slowpath.\n");
--
2.44.0.278.ge034bb2e1d-goog
Replace 3 instances of strncpy in ql4_mbx.c
No bugs exist in the current implementation as some care was taken to
ensure the write length was decreased by one to leave some space for a
NUL-byte. However, instead of using strncpy(dest, src, LEN-1) we can opt
for strscpy(dest, src, sizeof(dest)) which will result in
NUL-termination as well. It should be noted that the entire chap_table
is zero-allocated so the NUL-padding provided by strncpy is not needed.
While here, I noticed that MIN_CHAP_SECRET_LEN was not used anywhere.
Since strscpy gives us the number of bytes copied into the destination
buffer (or an -E2BIG) we can check both for an error during copying and
also for a non-length compliant secret. Add a new jump label so we can
properly clean up our chap_table should we have to abort due to bad
secret.
The third instance in this file involves some more peculiar handling of
strings:
| uint32_t mbox_cmd[MBOX_REG_COUNT];
| ...
| memset(&mbox_cmd, 0, sizeof(mbox_cmd));
| ...
| mbox_cmd[0] = MBOX_CMD_SET_PARAM;
| if (param == SET_DRVR_VERSION) {
| mbox_cmd[1] = SET_DRVR_VERSION;
| strncpy((char *)&mbox_cmd[2], QLA4XXX_DRIVER_VERSION,
| MAX_DRVR_VER_LEN - 1);
mbox_cmd has a size of 8:
| #define MBOX_REG_COUNT 8
.. and its type width is 4 bytes. Hence, we have 32 bytes to work with
here. The first 4 bytes are used as a flag for the MBOX_CMD_SET_PARAM.
The next 4 bytes are used for SET_DRVR_VERSION. We now have 32-8=24
bytes remaining -- which thankfully is what MAX_DRVR_VER_LEN is equal to
| #define MAX_DRVR_VER_LEN 24
.. and the thing we're copying into this pseudo-string buffer is
| #define QLA4XXX_DRIVER_VERSION "5.04.00-k6"
.. which is great because its less than 24 bytes (therefore we aren't
truncating the source).
All to say, there's no bug in the existing implementation (yay!) but we
can clean the code up a bit by using strscpy().
In ql4_os.c, there aren't any strncpy() uses to replace but there are
some existing strscpy() calls that could be made more idiomatic. Where
possible, use strscpy(dest, src, sizeof(dest)). Note that
chap_rec->password has a size of ISCSI_CHAP_AUTH_SECRET_MAX_LEN
| #define ISCSI_CHAP_AUTH_SECRET_MAX_LEN 256
.. while the current strscpy usage uses QL4_CHAP_MAX_SECRET_LEN
| #define QL4_CHAP_MAX_SECRET_LEN 100
.. however since chap_table->secret was set and bounded properly in its
string assignment its probably safe here to switch over to sizeof().
| struct iscsi_chap_rec {
...
| char username[ISCSI_CHAP_AUTH_NAME_MAX_LEN];
| uint8_t password[ISCSI_CHAP_AUTH_SECRET_MAX_LEN];
...
| };
| strscpy(chap_rec->password, chap_table->secret,
| QL4_CHAP_MAX_SECRET_LEN);
Reviewed-by: Kees Cook <[email protected]>
Signed-off-by: Justin Stitt <[email protected]>
---
drivers/scsi/qla4xxx/ql4_mbx.c | 17 ++++++++++++-----
drivers/scsi/qla4xxx/ql4_os.c | 14 +++++++-------
2 files changed, 19 insertions(+), 12 deletions(-)
diff --git a/drivers/scsi/qla4xxx/ql4_mbx.c b/drivers/scsi/qla4xxx/ql4_mbx.c
index 249f1d7021d4..75125d2021f5 100644
--- a/drivers/scsi/qla4xxx/ql4_mbx.c
+++ b/drivers/scsi/qla4xxx/ql4_mbx.c
@@ -1641,6 +1641,7 @@ int qla4xxx_set_chap(struct scsi_qla_host *ha, char *username, char *password,
struct ql4_chap_table *chap_table;
uint32_t chap_size = 0;
dma_addr_t chap_dma;
+ ssize_t secret_len;
chap_table = dma_pool_zalloc(ha->chap_dma_pool, GFP_KERNEL, &chap_dma);
if (chap_table == NULL) {
@@ -1652,9 +1653,13 @@ int qla4xxx_set_chap(struct scsi_qla_host *ha, char *username, char *password,
chap_table->flags |= BIT_6; /* peer */
else
chap_table->flags |= BIT_7; /* local */
- chap_table->secret_len = strlen(password);
- strncpy(chap_table->secret, password, MAX_CHAP_SECRET_LEN - 1);
- strncpy(chap_table->name, username, MAX_CHAP_NAME_LEN - 1);
+
+ secret_len = strscpy(chap_table->secret, password,
+ sizeof(chap_table->secret));
+ if (secret_len < MIN_CHAP_SECRET_LEN)
+ goto cleanup_chap_table;
+ chap_table->secret_len = (uint8_t)secret_len;
+ strscpy(chap_table->name, username, sizeof(chap_table->name));
chap_table->cookie = cpu_to_le16(CHAP_VALID_COOKIE);
if (is_qla40XX(ha)) {
@@ -1679,6 +1684,8 @@ int qla4xxx_set_chap(struct scsi_qla_host *ha, char *username, char *password,
memcpy((struct ql4_chap_table *)ha->chap_list + idx,
chap_table, sizeof(struct ql4_chap_table));
}
+
+cleanup_chap_table:
dma_pool_free(ha->chap_dma_pool, chap_table, chap_dma);
if (rval != QLA_SUCCESS)
ret = -EINVAL;
@@ -2281,8 +2288,8 @@ int qla4_8xxx_set_param(struct scsi_qla_host *ha, int param)
mbox_cmd[0] = MBOX_CMD_SET_PARAM;
if (param == SET_DRVR_VERSION) {
mbox_cmd[1] = SET_DRVR_VERSION;
- strncpy((char *)&mbox_cmd[2], QLA4XXX_DRIVER_VERSION,
- MAX_DRVR_VER_LEN - 1);
+ strscpy((char *)&mbox_cmd[2], QLA4XXX_DRIVER_VERSION,
+ MAX_DRVR_VER_LEN);
} else {
ql4_printk(KERN_ERR, ha, "%s: invalid parameter 0x%x\n",
__func__, param);
diff --git a/drivers/scsi/qla4xxx/ql4_os.c b/drivers/scsi/qla4xxx/ql4_os.c
index 675332e49a7b..17cccd14765f 100644
--- a/drivers/scsi/qla4xxx/ql4_os.c
+++ b/drivers/scsi/qla4xxx/ql4_os.c
@@ -799,10 +799,10 @@ static int qla4xxx_get_chap_list(struct Scsi_Host *shost, uint16_t chap_tbl_idx,
chap_rec->chap_tbl_idx = i;
strscpy(chap_rec->username, chap_table->name,
- ISCSI_CHAP_AUTH_NAME_MAX_LEN);
- strscpy(chap_rec->password, chap_table->secret,
- QL4_CHAP_MAX_SECRET_LEN);
- chap_rec->password_length = chap_table->secret_len;
+ sizeof(chap_rec->username));
+ chap_rec->password_length = strscpy(chap_rec->password,
+ chap_table->secret,
+ sizeof(chap_rec->password));
if (chap_table->flags & BIT_7) /* local */
chap_rec->chap_type = CHAP_TYPE_OUT;
@@ -6291,8 +6291,8 @@ static void qla4xxx_get_param_ddb(struct ddb_entry *ddb_entry,
tddb->tpgt = sess->tpgt;
tddb->port = conn->persistent_port;
- strscpy(tddb->iscsi_name, sess->targetname, ISCSI_NAME_SIZE);
- strscpy(tddb->ip_addr, conn->persistent_address, DDB_IPADDR_LEN);
+ strscpy(tddb->iscsi_name, sess->targetname, sizeof(tddb->iscsi_name));
+ strscpy(tddb->ip_addr, conn->persistent_address, sizeof(tddb->ip_addr));
}
static void qla4xxx_convert_param_ddb(struct dev_db_entry *fw_ddb_entry,
@@ -7792,7 +7792,7 @@ static int qla4xxx_sysfs_ddb_logout(struct iscsi_bus_flash_session *fnode_sess,
}
strscpy(flash_tddb->iscsi_name, fnode_sess->targetname,
- ISCSI_NAME_SIZE);
+ sizeof(flash_tddb->iscsi_name));
if (!strncmp(fnode_sess->portal_type, PORTAL_TYPE_IPV6, 4))
sprintf(flash_tddb->ip_addr, "%pI6", fnode_conn->ipaddress);
--
2.44.0.278.ge034bb2e1d-goog
Depending on the state of @compatible, we are going to do different
things with our @to buffer.
When @compatible is true we want a NUL-term'd and NUL-padded destination
buffer. Conversely, if @compatible is false we just want a space-padded
destination buffer (no NUL-term required).
As per:
/**
* scsi_dev_info_list_add_keyed - add one dev_info list entry.
* @compatible: if true, null terminate short strings. Otherwise space pad.
..
Note that we can't easily use `strtomem_pad` here as the size of the @to
buffer is unknown to the compiler due to indirection layers.
Now, the intent of the code is more clear (I probably didn't even need
to add a comment -- that's how clear it is).
Reviewed-by: Kees Cook <[email protected]>
Signed-off-by: Justin Stitt <[email protected]>
---
drivers/scsi/scsi_devinfo.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)
diff --git a/drivers/scsi/scsi_devinfo.c b/drivers/scsi/scsi_devinfo.c
index 3fcaf10a9dfe..2d3dbce25629 100644
--- a/drivers/scsi/scsi_devinfo.c
+++ b/drivers/scsi/scsi_devinfo.c
@@ -293,14 +293,16 @@ static void scsi_strcpy_devinfo(char *name, char *to, size_t to_length,
size_t from_length;
from_length = strlen(from);
- /* This zero-pads the destination */
- strncpy(to, from, to_length);
- if (from_length < to_length && !compatible) {
- /*
- * space pad the string if it is short.
- */
- memset(&to[from_length], ' ', to_length - from_length);
- }
+
+ /*
+ * null pad and null terminate if compatible
+ * otherwise space pad
+ */
+ if (compatible)
+ strscpy_pad(to, from, to_length);
+ else
+ memcpy_and_pad(to, to_length, from, from_length, ' ');
+
if (from_length > to_length)
printk(KERN_WARNING "%s: %s string '%s' is too long\n",
__func__, name, from);
--
2.44.0.278.ge034bb2e1d-goog
buffer->driver_version is sized 32:
| struct bmic_host_wellness_driver_version {
| ...
| char driver_version[32];
.. the source string "Linux " + DRIVER_VERISON is sized at 16. There's
really no bug in the existing code since the buffers are sized
appropriately with great care taken to manually NUL-terminate the
destination buffer. Nonetheless, let's make the swap over to strscpy()
for robustness' (and readability's) sake.
Reviewed-by: Kees Cook <[email protected]>
Signed-off-by: Justin Stitt <[email protected]>
---
drivers/scsi/smartpqi/smartpqi_init.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c
index ceff1ec13f9e..bfe6f42e8e96 100644
--- a/drivers/scsi/smartpqi/smartpqi_init.c
+++ b/drivers/scsi/smartpqi/smartpqi_init.c
@@ -1041,9 +1041,8 @@ static int pqi_write_driver_version_to_host_wellness(
buffer->driver_version_tag[1] = 'V';
put_unaligned_le16(sizeof(buffer->driver_version),
&buffer->driver_version_length);
- strncpy(buffer->driver_version, "Linux " DRIVER_VERSION,
- sizeof(buffer->driver_version) - 1);
- buffer->driver_version[sizeof(buffer->driver_version) - 1] = '\0';
+ strscpy(buffer->driver_version, "Linux " DRIVER_VERSION,
+ sizeof(buffer->driver_version));
buffer->dont_write_tag[0] = 'D';
buffer->dont_write_tag[1] = 'W';
buffer->end_tag[0] = 'Z';
--
2.44.0.278.ge034bb2e1d-goog