[ Upstream commit 3d75e766b58a7410d4e835c534e1b4664a8f62d0 ]
With clang's kernel control flow integrity (kCFI, CONFIG_CFI_CLANG),
indirect call targets are validated against the expected function pointer
prototype to make sure the call target is valid to help mitigate ROP
attacks. If they are not identical, there is a failure at run time, which
manifests as either a kernel panic or thread getting killed. A proposed
warning in clang aims to catch these at compile time, which reveals:
drivers/scsi/elx/libefc/efc_node.c:811:22: error: incompatible function pointer types assigning to 'void (*)(struct efc_sm_ctx *, u32, void *)' (aka 'void (*)(struct efc_sm_ctx *, unsigned int, void *)') from 'void (*)(struct efc_sm_ctx *, enum efc_sm_event, void *)' [-Werror,-Wincompatible-function-pointer-types-strict]
ctx->current_state = state;
^ ~~~~~
drivers/scsi/elx/libefc/efc_node.c:878:21: error: incompatible function pointer types assigning to 'void (*)(struct efc_sm_ctx *, u32, void *)' (aka 'void (*)(struct efc_sm_ctx *, unsigned int, void *)') from 'void (*)(struct efc_sm_ctx *, enum efc_sm_event, void *)' [-Werror,-Wincompatible-function-pointer-types-strict]
node->nodedb_state = state;
^ ~~~~~
drivers/scsi/elx/libefc/efc_node.c:905:6: error: incompatible function pointer types assigning to 'void (*)(struct efc_sm_ctx *, enum efc_sm_event, void *)' from 'void (*)(struct efc_sm_ctx *, u32, void *)' (aka 'void (*)(struct efc_sm_ctx *, unsigned int, void *)') [-Werror,-Wincompatible-function-pointer-types-strict]
pf = node->nodedb_state;
^ ~~~~~~~~~~~~~~~~~~
drivers/scsi/elx/libefc/efc_device.c:455:22: error: incompatible function pointer types assigning to 'void (*)(struct efc_sm_ctx *, u32, void *)' (aka 'void (*)(struct efc_sm_ctx *, unsigned int, void *)') from 'void (struct efc_sm_ctx *, enum efc_sm_event, void *)' [-Werror,-Wincompatible-function-pointer-types-strict]
node->nodedb_state = __efc_d_init;
^ ~~~~~~~~~~~~
drivers/scsi/elx/libefc/efc_sm.c:41:22: error: incompatible function pointer types assigning to 'void (*)(struct efc_sm_ctx *, u32, void *)' (aka 'void (*)(struct efc_sm_ctx *, unsigned int, void *)') from 'void (*)(struct efc_sm_ctx *, enum efc_sm_event, void *)' [-Werror,-Wincompatible-function-pointer-types-strict]
ctx->current_state = state;
^ ~~~~~
The type of the second parameter in the prototypes of ->current_state() and
->nodedb_state() ('u32') does not match the implementations, which have a
second parameter type of 'enum efc_sm_event'. Update the prototypes to have
the correct second parameter type, clearing up all the warnings and CFI
failures.
Link: https://github.com/ClangBuiltLinux/linux/issues/1750
Reported-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20221102161906.2781508-1-nathan@kernel.org
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
The kernel test robot flagged an warning for ".../efc_device.c:932:6:
warning: cast to smaller integer type 'enum efc_nport_topology' from 'void
*'"
For the topology events, the "arg" field is generically defined as a void *
and is used to pass different arguments. Most of the arguments are pointers
to data structures. But for the EFC_EVT_NPORT_TOPOLOGY_NOTIFY event, the
argument is an enum value, and the code is typecasting the void * to an
enum generating the warning.
Fix by converting the EFC_EVT_NPORT_TOPOLOGY_NOTIFY event to pass a pointer
to the enum, thus it's a straight-forward pointer dereference in the event
handler.
Link: https://lore.kernel.org/r/20210830231050.5951-1-jsmart2021@gmail.com
Fixes: 202bfdffae ("scsi: elx: libefc: FC node ELS and state handling")
Reported-by: kernel test robot <lkp@intel.com>
Co-developed-by: Ram Vegesna <ram.vegesna@broadcom.com>
Signed-off-by: Ram Vegesna <ram.vegesna@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
