From: Anthony Brandon <anthony@amarulasolutions.com> stable inclusion from stable-v6.6.122 commit df8a131a41ff6202d47f59452735787f2b71dd2d category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/13577 CVE: CVE-2025-71195 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit c7d436a6c1a274c1ac28d5fb3b8eb8f03b6d0e10 ] The max_register field is assigned the size of the register memory region instead of the offset of the last register. The result is that reading from the regmap via debugfs can cause a segmentation fault: tail /sys/kernel/debug/regmap/xdma.1.auto/registers Unable to handle kernel paging request at virtual address ffff800082f70000 Mem abort info: ESR = 0x0000000096000007 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x07: level 3 translation fault [...] Call trace: regmap_mmio_read32le+0x10/0x30 _regmap_bus_reg_read+0x74/0xc0 _regmap_read+0x68/0x198 regmap_read+0x54/0x88 regmap_read_debugfs+0x140/0x380 regmap_map_read_file+0x30/0x48 full_proxy_read+0x68/0xc8 vfs_read+0xcc/0x310 ksys_read+0x7c/0x120 __arm64_sys_read+0x24/0x40 invoke_syscall.constprop.0+0x64/0x108 do_el0_svc+0xb0/0xd8 el0_svc+0x38/0x130 el0t_64_sync_handler+0x120/0x138 el0t_64_sync+0x194/0x198 Code: aa1e03e9 d503201f f9400000 8b214000 (b9400000) ---[ end trace 0000000000000000 ]--- note: tail[1217] exited with irqs disabled note: tail[1217] exited with preempt_count 1 Segmentation fault Fixes: 17ce252266c7 ("dmaengine: xilinx: xdma: Add xilinx xdma driver") Reviewed-by: Lizhi Hou <lizhi.hou@amd.com> Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com> Reviewed-by: Alexander Stein <alexander.stein@ew.tq-group.com> Signed-off-by: Anthony Brandon <anthony@amarulasolutions.com> Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Yin Tirui <yintirui@huawei.com> --- drivers/dma/xilinx/xdma-regs.h | 1 + drivers/dma/xilinx/xdma.c | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/dma/xilinx/xdma-regs.h b/drivers/dma/xilinx/xdma-regs.h index dd98b4526b90..b19c173d8bfc 100644 --- a/drivers/dma/xilinx/xdma-regs.h +++ b/drivers/dma/xilinx/xdma-regs.h @@ -9,6 +9,7 @@ /* The length of register space exposed to host */ #define XDMA_REG_SPACE_LEN 65536 +#define XDMA_MAX_REG_OFFSET (XDMA_REG_SPACE_LEN - 4) /* * maximum number of DMA channels for each direction: diff --git a/drivers/dma/xilinx/xdma.c b/drivers/dma/xilinx/xdma.c index e0bfd129d563..dbab4c449914 100644 --- a/drivers/dma/xilinx/xdma.c +++ b/drivers/dma/xilinx/xdma.c @@ -38,7 +38,7 @@ static const struct regmap_config xdma_regmap_config = { .reg_bits = 32, .val_bits = 32, .reg_stride = 4, - .max_register = XDMA_REG_SPACE_LEN, + .max_register = XDMA_MAX_REG_OFFSET, }; /** -- 2.43.0