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R. Silva" Message-ID: Date: Mon, 20 Sep 2021 19:05:07 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.13.0 MIME-Version: 1.0 In-Reply-To: <20210918142138.17709-1-len.baker@gmx.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - gator4166.hostgator.com X-AntiAbuse: Original Domain - lists.ozlabs.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - embeddedor.com X-BWhitelist: no X-Source-IP: 187.162.31.110 X-Source-L: No X-Exim-ID: 1mSTDr-000Y7U-Iv X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: 187-162-31-110.static.axtel.net ([192.168.15.9]) [187.162.31.110]:33780 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 8 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kees Cook , linux-kernel@vger.kernel.org, kvm-ppc@vger.kernel.org, "Gustavo A. R. Silva" , linux-hardening@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On 9/18/21 09:21, Len Baker wrote: > There is a regular need in the kernel to provide a way to declare having > a dynamically sized set of trailing elements in a structure. Kernel code > should always use "flexible array members" [1] for these cases. The > older style of one-element or zero-length arrays should no longer be > used[2]. > > Also, make use of the struct_size() helper in kzalloc(). > > [1] https://en.wikipedia.org/wiki/Flexible_array_member > [2] https://www.kernel.org/doc/html/latest/process/deprecated.html#zero-length-and-one-element-arrays > > Signed-off-by: Len Baker Reviewed-by: Gustavo A. R. Silva Thanks -- Gustavo > --- > arch/powerpc/include/asm/kvm_host.h | 2 +- > arch/powerpc/kvm/book3s_64_vio.c | 3 +-- > 2 files changed, 2 insertions(+), 3 deletions(-) > > diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h > index 080a7feb7731..3aed653373a5 100644 > --- a/arch/powerpc/include/asm/kvm_host.h > +++ b/arch/powerpc/include/asm/kvm_host.h > @@ -190,7 +190,7 @@ struct kvmppc_spapr_tce_table { > u64 size; /* window size in pages */ > struct list_head iommu_tables; > struct mutex alloc_lock; > - struct page *pages[0]; > + struct page *pages[]; > }; > > /* XICS components, defined in book3s_xics.c */ > diff --git a/arch/powerpc/kvm/book3s_64_vio.c b/arch/powerpc/kvm/book3s_64_vio.c > index 6365087f3160..d42b4b6d4a79 100644 > --- a/arch/powerpc/kvm/book3s_64_vio.c > +++ b/arch/powerpc/kvm/book3s_64_vio.c > @@ -295,8 +295,7 @@ long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm, > return ret; > > ret = -ENOMEM; > - stt = kzalloc(sizeof(*stt) + npages * sizeof(struct page *), > - GFP_KERNEL); > + stt = kzalloc(struct_size(stt, pages, npages), GFP_KERNEL); > if (!stt) > goto fail_acct; > > -- > 2.25.1 >