From 9184a711f3cdcc7632ef8d12237c8b2cac653bbe Mon Sep 17 00:00:00 2001
From: Kees Cook <keescook@chromium.org>
Date: Thu, 5 May 2022 16:31:01 -0700
Subject: [PATCH 03/32] net: chelsio: cxgb4: Avoid potential negative array
 offset
Git-commit: 1c7ab9cd98b78bef1657a5db7204d8d437e24c94
References: git-fixes
Patch-mainline: v5.18-rc7

Using min_t(int, ...) as a potential array index implies to the compiler
that negative offsets should be allowed. This is not the case, though.
Replace "int" with "unsigned int". Fixes the following warning exposed
under future CONFIG_FORTIFY_SOURCE improvements:

In file included from include/linux/string.h:253,
                 from include/linux/bitmap.h:11,
                 from include/linux/cpumask.h:12,
                 from include/linux/smp.h:13,
                 from include/linux/lockdep.h:14,
                 from include/linux/rcupdate.h:29,
                 from include/linux/rculist.h:11,
                 from include/linux/pid.h:5,
                 from include/linux/sched.h:14,
                 from include/linux/delay.h:23,
                 from drivers/net/ethernet/chelsio/cxgb4/t4_hw.c:35:
drivers/net/ethernet/chelsio/cxgb4/t4_hw.c: In function 't4_get_raw_vpd_params':
include/linux/fortify-string.h:46:33: warning: '__builtin_memcpy' pointer overflow between offset 29 and size [2147483648, 4294967295] [-Warray-bounds]
   46 | #define __underlying_memcpy     __builtin_memcpy
      |                                 ^
include/linux/fortify-string.h:388:9: note: in expansion of macro '__underlying_memcpy'
  388 |         __underlying_##op(p, q, __fortify_size);                        \
      |         ^~~~~~~~~~~~~
include/linux/fortify-string.h:433:26: note: in expansion of macro '__fortify_memcpy_chk'
  433 | #define memcpy(p, q, s)  __fortify_memcpy_chk(p, q, s,                  \
      |                          ^~~~~~~~~~~~~~~~~~~~
drivers/net/ethernet/chelsio/cxgb4/t4_hw.c:2796:9: note: in expansion of macro 'memcpy'
 2796 |         memcpy(p->id, vpd + id, min_t(int, id_len, ID_LEN));
      |         ^~~~~~
include/linux/fortify-string.h:46:33: warning: '__builtin_memcpy' pointer overflow between offset 0 and size [2147483648, 4294967295] [-Warray-bounds]
   46 | #define __underlying_memcpy     __builtin_memcpy
      |                                 ^
include/linux/fortify-string.h:388:9: note: in expansion of macro '__underlying_memcpy'
  388 |         __underlying_##op(p, q, __fortify_size);                        \
      |         ^~~~~~~~~~~~~
include/linux/fortify-string.h:433:26: note: in expansion of macro '__fortify_memcpy_chk'
  433 | #define memcpy(p, q, s)  __fortify_memcpy_chk(p, q, s,                  \
      |                          ^~~~~~~~~~~~~~~~~~~~
drivers/net/ethernet/chelsio/cxgb4/t4_hw.c:2798:9: note: in expansion of macro 'memcpy'
 2798 |         memcpy(p->sn, vpd + sn, min_t(int, sn_len, SERNUM_LEN));
      |         ^~~~~~

Additionally remove needless cast from u8[] to char * in last strim()
call.

Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/lkml/202205031926.FVP7epJM-lkp@intel.com
Fixes: fc9279298e3a ("cxgb4: Search VPD with pci_vpd_find_ro_info_keyword()")
Fixes: 24c521f81c30 ("cxgb4: Use pci_vpd_find_id_string() to find VPD ID string")
Cc: Raju Rangoju <rajur@chelsio.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220505233101.1224230-1-keescook@chromium.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Denis Kirjanov <denis.kirjanov@suse.com>
---
 drivers/net/ethernet/chelsio/cxgb4/t4_hw.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c b/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c
index d2be92ed133d..1e812f159fe0 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c
@@ -2796,14 +2796,14 @@ int t4_get_raw_vpd_params(struct adapter *adapter, struct vpd_params *p)
 		goto out;
 	na = ret;
 
-	memcpy(p->id, vpd + PCI_VPD_LRDT_TAG_SIZE, min_t(int, id_len, ID_LEN));
+	memcpy(p->id, vpd + PCI_VPD_LRDT_TAG_SIZE, min_t(unsigned int, id_len, ID_LEN));
 	strim(p->id);
-	memcpy(p->sn, vpd + sn, min_t(int, sn_len, SERNUM_LEN));
+	memcpy(p->sn, vpd + sn, min_t(unsigned int, sn_len, SERNUM_LEN));
 	strim(p->sn);
-	memcpy(p->pn, vpd + pn, min_t(int, pn_len, PN_LEN));
+	memcpy(p->pn, vpd + pn, min_t(unsigned int, pn_len, PN_LEN));
 	strim(p->pn);
-	memcpy(p->na, vpd + na, min_t(int, na_len, MACADDR_LEN));
-	strim((char *)p->na);
+	memcpy(p->na, vpd + na, min_t(unsigned int, na_len, MACADDR_LEN));
+	strim(p->na);
 
 out:
 	vfree(vpd);
-- 
2.16.4