| Message ID | 20230127223853.never.014-kees@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | net: ethernet: mtk_eth_soc: Avoid truncating allocation | expand |
On Fri, Jan 27, 2023 at 02:38:54PM -0800, Kees Cook wrote: > There doesn't appear to be a reason to truncate the allocation used for > flow_info, so do a full allocation and remove the unused empty struct. > GCC does not like having a reference to an object that has been > partially allocated, as bounds checking may become impossible when > such an object is passed to other code. Seen with GCC 13: > > ../drivers/net/ethernet/mediatek/mtk_ppe.c: In function 'mtk_foe_entry_commit_subflow': > ../drivers/net/ethernet/mediatek/mtk_ppe.c:623:18: warning: array subscript 'struct mtk_flow_entry[0]' is partly outside array bounds of 'unsigned char[48]' [-Warray-bounds=] > 623 | flow_info->l2_data.base_flow = entry; > | ^~ > ... > Signed-off-by: Kees Cook <keescook@chromium.org> > --- > drivers/net/ethernet/mediatek/mtk_ppe.c | 3 +-- > drivers/net/ethernet/mediatek/mtk_ppe.h | 1 - > 2 files changed, 1 insertion(+), 3 deletions(-) Reviewed-by: Simon Horman <simon.horman@corigine.com>
Hello: This patch was applied to netdev/net.git (master) by Paolo Abeni <pabeni@redhat.com>: On Fri, 27 Jan 2023 14:38:54 -0800 you wrote: > There doesn't appear to be a reason to truncate the allocation used for > flow_info, so do a full allocation and remove the unused empty struct. > GCC does not like having a reference to an object that has been > partially allocated, as bounds checking may become impossible when > such an object is passed to other code. Seen with GCC 13: > > ../drivers/net/ethernet/mediatek/mtk_ppe.c: In function 'mtk_foe_entry_commit_subflow': > ../drivers/net/ethernet/mediatek/mtk_ppe.c:623:18: warning: array subscript 'struct mtk_flow_entry[0]' is partly outside array bounds of 'unsigned char[48]' [-Warray-bounds=] > 623 | flow_info->l2_data.base_flow = entry; > | ^~ > > [...] Here is the summary with links: - net: ethernet: mtk_eth_soc: Avoid truncating allocation https://git.kernel.org/netdev/net/c/f3eceaed9edd You are awesome, thank you!
diff --git a/drivers/net/ethernet/mediatek/mtk_ppe.c b/drivers/net/ethernet/mediatek/mtk_ppe.c index 451a87b1bc20..6883eb34cd8b 100644 --- a/drivers/net/ethernet/mediatek/mtk_ppe.c +++ b/drivers/net/ethernet/mediatek/mtk_ppe.c @@ -615,8 +615,7 @@ mtk_foe_entry_commit_subflow(struct mtk_ppe *ppe, struct mtk_flow_entry *entry, u32 ib1_mask = mtk_get_ib1_pkt_type_mask(ppe->eth) | MTK_FOE_IB1_UDP; int type; - flow_info = kzalloc(offsetof(struct mtk_flow_entry, l2_data.end), - GFP_ATOMIC); + flow_info = kzalloc(sizeof(*flow_info), GFP_ATOMIC); if (!flow_info) return; diff --git a/drivers/net/ethernet/mediatek/mtk_ppe.h b/drivers/net/ethernet/mediatek/mtk_ppe.h index 16b02e1d4649..5e8bc48252b1 100644 --- a/drivers/net/ethernet/mediatek/mtk_ppe.h +++ b/drivers/net/ethernet/mediatek/mtk_ppe.h @@ -279,7 +279,6 @@ struct mtk_flow_entry { struct { struct mtk_flow_entry *base_flow; struct hlist_node list; - struct {} end; } l2_data; }; struct rhash_head node;
There doesn't appear to be a reason to truncate the allocation used for flow_info, so do a full allocation and remove the unused empty struct. GCC does not like having a reference to an object that has been partially allocated, as bounds checking may become impossible when such an object is passed to other code. Seen with GCC 13: ../drivers/net/ethernet/mediatek/mtk_ppe.c: In function 'mtk_foe_entry_commit_subflow': ../drivers/net/ethernet/mediatek/mtk_ppe.c:623:18: warning: array subscript 'struct mtk_flow_entry[0]' is partly outside array bounds of 'unsigned char[48]' [-Warray-bounds=] 623 | flow_info->l2_data.base_flow = entry; | ^~ Cc: Felix Fietkau <nbd@nbd.name> Cc: John Crispin <john@phrozen.org> Cc: Sean Wang <sean.wang@mediatek.com> Cc: Mark Lee <Mark-MC.Lee@mediatek.com> Cc: Lorenzo Bianconi <lorenzo@kernel.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: netdev@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-mediatek@lists.infradead.org Signed-off-by: Kees Cook <keescook@chromium.org> --- drivers/net/ethernet/mediatek/mtk_ppe.c | 3 +-- drivers/net/ethernet/mediatek/mtk_ppe.h | 1 - 2 files changed, 1 insertion(+), 3 deletions(-)