From c95998811807d897ca112ea62d66716ed733d058 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Tue, 29 May 2018 06:03:53 +0000 Subject: [PATCH] powerpc/64: Fix strncpy() related build failures with GCC 8.1 GCC 8.1 warns about possible string truncation: arch/powerpc/kernel/nvram_64.c:1042:2: error: 'strncpy' specified bound 12 equals destination size [-Werror=stringop-truncation] strncpy(new_part->header.name, name, 12); arch/powerpc/platforms/ps3/repository.c:106:2: error: 'strncpy' output truncated before terminating nul copying 8 bytes from a string of the same length [-Werror=stringop-truncation] strncpy((char *)&n, text, 8); Fix it by using memcpy(). To make that safe we need to ensure the destination is pre-zeroed. Use kzalloc() in the nvram code and initialise the u64 to zero in the ps3 code. Signed-off-by: Christophe Leroy [mpe: Use kzalloc() in the nvram code, flesh out change log] Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/nvram_64.c | 4 ++-- arch/powerpc/platforms/ps3/repository.c | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/kernel/nvram_64.c b/arch/powerpc/kernel/nvram_64.c index ba681dac7b46..22e9d281324d 100644 --- a/arch/powerpc/kernel/nvram_64.c +++ b/arch/powerpc/kernel/nvram_64.c @@ -1030,7 +1030,7 @@ loff_t __init nvram_create_partition(const char *name, int sig, return -ENOSPC; /* Create our OS partition */ - new_part = kmalloc(sizeof(*new_part), GFP_KERNEL); + new_part = kzalloc(sizeof(*new_part), GFP_KERNEL); if (!new_part) { pr_err("%s: kmalloc failed\n", __func__); return -ENOMEM; @@ -1039,7 +1039,7 @@ loff_t __init nvram_create_partition(const char *name, int sig, new_part->index = free_part->index; new_part->header.signature = sig; new_part->header.length = size; - strncpy(new_part->header.name, name, 12); + memcpy(new_part->header.name, name, strnlen(name, sizeof(new_part->header.name))); new_part->header.checksum = nvram_checksum(&new_part->header); rc = nvram_write_header(new_part); diff --git a/arch/powerpc/platforms/ps3/repository.c b/arch/powerpc/platforms/ps3/repository.c index 50dbaf24b1ee..e49c887787c4 100644 --- a/arch/powerpc/platforms/ps3/repository.c +++ b/arch/powerpc/platforms/ps3/repository.c @@ -101,9 +101,9 @@ static u64 make_first_field(const char *text, u64 index) static u64 make_field(const char *text, u64 index) { - u64 n; + u64 n = 0; - strncpy((char *)&n, text, 8); + memcpy((char *)&n, text, strnlen(text, sizeof(n))); return n + index; }