From: Gal Pressman <gal@nvidia.com> mainline inclusion from mainline-v7.2-rc5 commit 11c057d23465c7a5817a7284c896d19d54c0b616 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/17144 CVE: CVE-2026-68293 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- The MCIA register can return up to 32 dwords (128 bytes) when the device advertises the mcia_32dwords capability, but struct mlx5_ifc_mcia_reg_bits only defines dword_0..11, leaving room for just 12 dwords (48 bytes) of data. mlx5_query_mcia() clamps the read size to mlx5_mcia_max_bytes() and then memcpy()s that many bytes out of the register, potentially reading past the end of the 'out' buffer. On kernels built with FORTIFY_SOURCE this is caught as a buffer overflow while reading the module EEPROM via ethtool: detected buffer overflow in memcpy kernel BUG at lib/string_helpers.c:1048! RIP: 0010:fortify_panic+0x13/0x20 Call Trace: mlx5_query_mcia.isra.0+0x200/0x210 [mlx5_core] mlx5_query_module_eeprom_by_page+0x4a/0xa0 [mlx5_core] mlx5e_get_module_eeprom_by_page+0xbb/0x120 [mlx5_core] eeprom_prepare_data+0xf3/0x170 ethnl_default_doit+0xf1/0x3b0 Extend the mcia_reg layout to 32 dwords. Fixes: 271907ee2f29 ("net/mlx5: Query the maximum MCIA register read size from firmware") Signed-off-by: Gal Pressman <gal@nvidia.com> Reviewed-by: Alex Lazar <alazar@nvidia.com> Signed-off-by: Tariq Toukan <tariqt@nvidia.com> Link: https://patch.msgid.link/20260717072338.1240582-1-tariqt@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Conflicts: drivers/net/ethernet/mellanox/mlx5/core/port.c [Commit 2e4c44b12f4d ("net/mlx5: Refactor EEPROM query error handling to return status separately") was not merged. Context conflicts.] Signed-off-by: Yi Yang <yiyang13@huawei.com> --- drivers/net/ethernet/mellanox/mlx5/core/port.c | 4 ++-- include/linux/mlx5/mlx5_ifc.h | 13 +------------ 2 files changed, 3 insertions(+), 14 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/port.c b/drivers/net/ethernet/mellanox/mlx5/core/port.c index a5622b44385e..ec739b2f0ada 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/port.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/port.c @@ -316,7 +316,7 @@ static int mlx5_query_module_id(struct mlx5_core_dev *dev, int module_num, status); return -EIO; } - ptr = MLX5_ADDR_OF(mcia_reg, out, dword_0); + ptr = MLX5_ADDR_OF(mcia_reg, out, dwords); *module_id = ptr[0]; @@ -401,7 +401,7 @@ static int mlx5_query_mcia(struct mlx5_core_dev *dev, return -EIO; } - ptr = MLX5_ADDR_OF(mcia_reg, out, dword_0); + ptr = MLX5_ADDR_OF(mcia_reg, out, dwords); memcpy(data, ptr, size); return size; diff --git a/include/linux/mlx5/mlx5_ifc.h b/include/linux/mlx5/mlx5_ifc.h index c59fd31719a1..573461c9dced 100644 --- a/include/linux/mlx5/mlx5_ifc.h +++ b/include/linux/mlx5/mlx5_ifc.h @@ -11320,18 +11320,7 @@ struct mlx5_ifc_mcia_reg_bits { u8 reserved_at_60[0x20]; - u8 dword_0[0x20]; - u8 dword_1[0x20]; - u8 dword_2[0x20]; - u8 dword_3[0x20]; - u8 dword_4[0x20]; - u8 dword_5[0x20]; - u8 dword_6[0x20]; - u8 dword_7[0x20]; - u8 dword_8[0x20]; - u8 dword_9[0x20]; - u8 dword_10[0x20]; - u8 dword_11[0x20]; + u8 dwords[0x400]; }; struct mlx5_ifc_dcbx_param_bits { -- 2.25.1