2024-02-13 10:08:21

by Arnd Bergmann

[permalink] [raw]
Subject: [PATCH] scsi: csiostor: avoid function pointer casts

From: Arnd Bergmann <[email protected]>

csiostor uses function pointer casts to keep the csio_ln_ev state machine
hidden, but this causes warnings about control flow integrity (KCFI) violations
in clang-16 and higher:

drivers/scsi/csiostor/csio_lnode.c:1098:33: error: cast from 'void (*)(struct csio_lnode *, enum csio_ln_ev)' to 'csio_sm_state_t' (aka 'void (*)(void *, unsigned int)') converts to incompatible function type [-Werror,-Wcast-function-type-strict]
1098 | return (csio_get_state(ln) == ((csio_sm_state_t)csio_lns_ready));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/scsi/csiostor/csio_lnode.c:1369:29: error: cast from 'void (*)(struct csio_lnode *, enum csio_ln_ev)' to 'csio_sm_state_t' (aka 'void (*)(void *, unsigned int)') converts to incompatible function type [-Werror,-Wcast-function-type-strict]
1369 | if (csio_get_state(ln) == ((csio_sm_state_t)csio_lns_uninit)) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/scsi/csiostor/csio_lnode.c:1373:29: error: cast from 'void (*)(struct csio_lnode *, enum csio_ln_ev)' to 'csio_sm_state_t' (aka 'void (*)(void *, unsigned int)') converts to incompatible function type [-Werror,-Wcast-function-type-strict]
1373 | if (csio_get_state(ln) == ((csio_sm_state_t)csio_lns_ready)) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/scsi/csiostor/csio_lnode.c:1377:29: error: cast from 'void (*)(struct csio_lnode *, enum csio_ln_ev)' to 'csio_sm_state_t' (aka 'void (*)(void *, unsigned int)') converts to incompatible function type [-Werror,-Wcast-function-type-strict]
1377 | if (csio_get_state(ln) == ((csio_sm_state_t)csio_lns_offline)) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Move the enum into a shared header so the correct types can be used without the
need for casts.

Fixes: a3667aaed569 ("[SCSI] csiostor: Chelsio FCoE offload driver")
Signed-off-by: Arnd Bergmann <[email protected]>
---
drivers/scsi/csiostor/csio_defs.h | 18 ++++++++++++++++--
drivers/scsi/csiostor/csio_lnode.c | 8 ++++----
drivers/scsi/csiostor/csio_lnode.h | 13 -------------
3 files changed, 20 insertions(+), 19 deletions(-)

diff --git a/drivers/scsi/csiostor/csio_defs.h b/drivers/scsi/csiostor/csio_defs.h
index c38017b4af98..e50e93e7fe5a 100644
--- a/drivers/scsi/csiostor/csio_defs.h
+++ b/drivers/scsi/csiostor/csio_defs.h
@@ -73,7 +73,21 @@ csio_list_deleted(struct list_head *list)
#define csio_list_prev(elem) (((struct list_head *)(elem))->prev)

/* State machine */
-typedef void (*csio_sm_state_t)(void *, uint32_t);
+struct csio_lnode;
+
+/* State machine evets */
+enum csio_ln_ev {
+ CSIO_LNE_NONE = (uint32_t)0,
+ CSIO_LNE_LINKUP,
+ CSIO_LNE_FAB_INIT_DONE,
+ CSIO_LNE_LINK_DOWN,
+ CSIO_LNE_DOWN_LINK,
+ CSIO_LNE_LOGO,
+ CSIO_LNE_CLOSE,
+ CSIO_LNE_MAX_EVENT,
+};
+
+typedef void (*csio_sm_state_t)(struct csio_lnode *ln, enum csio_ln_ev evt);

struct csio_sm {
struct list_head sm_list;
@@ -83,7 +97,7 @@ struct csio_sm {
static inline void
csio_set_state(void *smp, void *state)
{
- ((struct csio_sm *)smp)->sm_state = (csio_sm_state_t)state;
+ ((struct csio_sm *)smp)->sm_state = state;
}

static inline void
diff --git a/drivers/scsi/csiostor/csio_lnode.c b/drivers/scsi/csiostor/csio_lnode.c
index d5ac93897023..5b3ffefae476 100644
--- a/drivers/scsi/csiostor/csio_lnode.c
+++ b/drivers/scsi/csiostor/csio_lnode.c
@@ -1095,7 +1095,7 @@ csio_handle_link_down(struct csio_hw *hw, uint8_t portid, uint32_t fcfi,
int
csio_is_lnode_ready(struct csio_lnode *ln)
{
- return (csio_get_state(ln) == ((csio_sm_state_t)csio_lns_ready));
+ return (csio_get_state(ln) == csio_lns_ready);
}

/*****************************************************************************/
@@ -1366,15 +1366,15 @@ csio_free_fcfinfo(struct kref *kref)
void
csio_lnode_state_to_str(struct csio_lnode *ln, int8_t *str)
{
- if (csio_get_state(ln) == ((csio_sm_state_t)csio_lns_uninit)) {
+ if (csio_get_state(ln) == csio_lns_uninit) {
strcpy(str, "UNINIT");
return;
}
- if (csio_get_state(ln) == ((csio_sm_state_t)csio_lns_ready)) {
+ if (csio_get_state(ln) == csio_lns_ready) {
strcpy(str, "READY");
return;
}
- if (csio_get_state(ln) == ((csio_sm_state_t)csio_lns_offline)) {
+ if (csio_get_state(ln) == csio_lns_offline) {
strcpy(str, "OFFLINE");
return;
}
diff --git a/drivers/scsi/csiostor/csio_lnode.h b/drivers/scsi/csiostor/csio_lnode.h
index 372a67d122d3..607698a0f063 100644
--- a/drivers/scsi/csiostor/csio_lnode.h
+++ b/drivers/scsi/csiostor/csio_lnode.h
@@ -53,19 +53,6 @@
extern int csio_fcoe_rnodes;
extern int csio_fdmi_enable;

-/* State machine evets */
-enum csio_ln_ev {
- CSIO_LNE_NONE = (uint32_t)0,
- CSIO_LNE_LINKUP,
- CSIO_LNE_FAB_INIT_DONE,
- CSIO_LNE_LINK_DOWN,
- CSIO_LNE_DOWN_LINK,
- CSIO_LNE_LOGO,
- CSIO_LNE_CLOSE,
- CSIO_LNE_MAX_EVENT,
-};
-
-
struct csio_fcf_info {
struct list_head list;
uint8_t priority;
--
2.39.2



2024-02-15 20:15:00

by Martin K. Petersen

[permalink] [raw]
Subject: Re: [PATCH] scsi: csiostor: avoid function pointer casts


Arnd,

> csiostor uses function pointer casts to keep the csio_ln_ev state
> machine hidden, but this causes warnings about control flow integrity
> (KCFI) violations in clang-16 and higher:

Applied to 6.9/scsi-staging, thanks!

--
Martin K. Petersen Oracle Linux Engineering