From f8d0efb112275444c03b76ee2376f0055d12aeba Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Mon, 11 Jun 2018 21:33:35 -0700 Subject: [PATCH] nfp: don't pad strings in nfp_cpp_resource_find() to avoid gcc 8 warning MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Once upon a time nfp_cpp_resource_find() took a name parameter, which could be any user-chosen string. Resources are identified by a CRC32 hash of a 8 byte string, so we had to pad user input with zeros to make sure CRC32 gave the correct result. Since then nfp_cpp_resource_find() was made to operate on allocated resources only (struct nfp_resource). We kzalloc those so there is no need to pad the strings and use memcmp. This avoids a GCC 8 stringop-truncation warning: In function ‘nfp_cpp_resource_find’, inlined from ‘nfp_resource_try_acquire’ at .../nfpcore/nfp_resource.c:153:8, inlined from ‘nfp_resource_acquire’ at .../nfpcore/nfp_resource.c:206:9: .../nfpcore/nfp_resource.c:108:2: warning: strncpy’ output may be truncated copying 8 bytes from a string of length 8 [-Wstringop-truncation] strncpy(name_pad, res->name, sizeof(name_pad)); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Signed-off-by: Jakub Kicinski Reviewed-by: Dirk van der Merwe Signed-off-by: David S. Miller --- drivers/net/ethernet/netronome/nfp/nfpcore/nfp_resource.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_resource.c b/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_resource.c index 2dd89db..d32af59 100644 --- a/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_resource.c +++ b/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_resource.c @@ -98,21 +98,18 @@ struct nfp_resource { static int nfp_cpp_resource_find(struct nfp_cpp *cpp, struct nfp_resource *res) { - char name_pad[NFP_RESOURCE_ENTRY_NAME_SZ] = {}; struct nfp_resource_entry entry; u32 cpp_id, key; int ret, i; cpp_id = NFP_CPP_ID(NFP_RESOURCE_TBL_TARGET, 3, 0); /* Atomic read */ - strncpy(name_pad, res->name, sizeof(name_pad)); - /* Search for a matching entry */ - if (!memcmp(name_pad, NFP_RESOURCE_TBL_NAME "\0\0\0\0\0\0\0\0", 8)) { + if (!strcmp(res->name, NFP_RESOURCE_TBL_NAME)) { nfp_err(cpp, "Grabbing device lock not supported\n"); return -EOPNOTSUPP; } - key = crc32_posix(name_pad, sizeof(name_pad)); + key = crc32_posix(res->name, NFP_RESOURCE_ENTRY_NAME_SZ); for (i = 0; i < NFP_RESOURCE_TBL_ENTRIES; i++) { u64 addr = NFP_RESOURCE_TBL_BASE + -- 2.7.4