BACKPORT qed: Fix copying 2 strings

The strscpy() was a recent fix (net: qed: use correct strncpy() size) to
prevent passing the length of the source buffer to strncpy() and guarantee
null termination.
It misses the goal of overwriting only the first 3 characters in
"???_BIG_RAM" and "???_RAM" while keeping the rest of the string.
Use strncpy() with the length of 3, without null termination.

Signed-off-by: Denis Bolotin <denis.bolotin@cavium.com>
Signed-off-by: Michal Kalderon <michal.kalderon@cavium.com>

diff --git a/patches/0005-BACKPORT-qed-Fix-copying-2-strings.patch b/patches/0005-BACKPORT-qed-Fix-copying-2-strings.patch
new file mode 100644 (file)
index 0000000..ff5ec98
--- /dev/null
+++ b/patches/0005-BACKPORT-qed-Fix-copying-2-strings.patch
@@ -0,0 +1,45 @@
+From c7d852e301d834949e570920db808201bdc51a22 Mon Sep 17 00:00:00 2001
+From: Denis Bolotin <denis.bolotin@cavium.com>
+Date: Tue, 24 Apr 2018 15:32:53 +0300
+Subject: [PATCH] qed: Fix copying 2 strings
+
+The strscpy() was a recent fix (net: qed: use correct strncpy() size) to
+prevent passing the length of the source buffer to strncpy() and guarantee
+null termination.
+It misses the goal of overwriting only the first 3 characters in
+"???_BIG_RAM" and "???_RAM" while keeping the rest of the string.
+Use strncpy() with the length of 3, without null termination.
+
+Signed-off-by: Denis Bolotin <denis.bolotin@cavium.com>
+Signed-off-by: Ariel Elior <ariel.elior@cavium.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/ethernet/qlogic/qed/qed_debug.c | 5 +++--
+ 1 file changed, 3 insertions(+), 2 deletions(-)
+
+diff --git a/drivers/net/ethernet/qlogic/qed/qed_debug.c b/drivers/net/ethernet/qlogic/qed/qed_debug.c
+index b3211c7..39124b5 100644
+--- a/drivers/net/ethernet/qlogic/qed/qed_debug.c
++++ b/drivers/net/ethernet/qlogic/qed/qed_debug.c
+@@ -419,6 +419,7 @@ struct phy_defs {
+ #define NUM_RSS_MEM_TYPES             5
+ 
+ #define NUM_BIG_RAM_TYPES             3
++#define BIG_RAM_NAME_LEN              3
+ 
+ #define NUM_PHY_TBUS_ADDRESSES                2048
+ #define PHY_DUMP_SIZE_DWORDS          (NUM_PHY_TBUS_ADDRESSES / 2)
+@@ -3650,8 +3651,8 @@ static u32 qed_grc_dump_big_ram(struct qed_hwfn *p_hwfn,
+                    BIT(big_ram->is_256b_bit_offset[dev_data->chip_id]) ? 256
+                                                                        : 128;
+ 
+-      strscpy(type_name, big_ram->instance_name, sizeof(type_name));
+-      strscpy(mem_name, big_ram->instance_name, sizeof(mem_name));
++      strncpy(type_name, big_ram->instance_name, BIG_RAM_NAME_LEN);
++      strncpy(mem_name, big_ram->instance_name, BIG_RAM_NAME_LEN);
+ 
+       /* Dump memory header */
+       offset += qed_grc_dump_mem_hdr(p_hwfn,
+-- 
+2.9.5
+