From: Bitan Biswas bbiswas@nvidia.com
commit 16bb7abc4a6b9defffa294e4dc28383e62a1dbcf upstream.
nvmem_cell_info_to_nvmem_cell implementation has static allocation of name. nvmem_add_cells_from_of() call may return error and kfree name results in memory abort. Use kstrdup_const() and kfree_const calls for name alloc and free.
Unable to handle kernel paging request at virtual address ffffffffffe44888 Mem abort info: ESR = 0x96000006 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000006 CM = 0, WnR = 0 swapper pgtable: 64k pages, 48-bit VAs, pgdp=00000000815d0000 [ffffffffffe44888] pgd=0000000081d30803, pud=0000000081d30803, pmd=0000000000000000 Internal error: Oops: 96000006 [#1] PREEMPT SMP Modules linked in: CPU: 2 PID: 43 Comm: kworker/2:1 Tainted Hardware name: quill (DT) Workqueue: events deferred_probe_work_func pstate: a0000005 (NzCv daif -PAN -UAO) pc : kfree+0x38/0x278 lr : nvmem_cell_drop+0x68/0x80 sp : ffff80001284f9d0 x29: ffff80001284f9d0 x28: ffff0001f677e830 x27: ffff800011b0b000 x26: ffff0001c36e1008 x25: ffff8000112ad000 x24: ffff8000112c9000 x23: ffffffffffffffea x22: ffff800010adc7f0 x21: ffffffffffe44880 x20: ffff800011b0b068 x19: ffff80001122d380 x18: ffffffffffffffff x17: 00000000d5cb4756 x16: 0000000070b193b8 x15: ffff8000119538c8 x14: 0720072007200720 x13: 07200720076e0772 x12: 07750762072d0765 x11: 0773077507660765 x10: 072f073007300730 x9 : 0730073207380733 x8 : 0000000000000151 x7 : 07660765072f0720 x6 : ffff0001c00e0f00 x5 : 0000000000000000 x4 : ffff0001c0b43800 x3 : ffff800011b0b068 x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffffffdfffe00000 Call trace: kfree+0x38/0x278 nvmem_cell_drop+0x68/0x80 nvmem_device_remove_all_cells+0x2c/0x50 nvmem_register.part.9+0x520/0x628 devm_nvmem_register+0x48/0xa0 tegra_fuse_probe+0x140/0x1f0 platform_drv_probe+0x50/0xa0 really_probe+0x108/0x348 driver_probe_device+0x58/0x100 __device_attach_driver+0x90/0xb0 bus_for_each_drv+0x64/0xc8 __device_attach+0xd8/0x138 device_initial_probe+0x10/0x18 bus_probe_device+0x90/0x98 deferred_probe_work_func+0x74/0xb0 process_one_work+0x1e0/0x358 worker_thread+0x208/0x488 kthread+0x118/0x120 ret_from_fork+0x10/0x18 Code: d350feb5 f2dffbe0 aa1e03f6 8b151815 (f94006a0) ---[ end trace 49b1303c6b83198e ]---
Fixes: badcdff107cbf ("nvmem: Convert to using %pOFn instead of device_node.name") Signed-off-by: Bitan Biswas bbiswas@nvidia.com Cc: stable stable@vger.kernel.org Signed-off-by: Srinivas Kandagatla srinivas.kandagatla@linaro.org Link: https://lore.kernel.org/r/20200109104017.6249-5-srinivas.kandagatla@linaro.o... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/nvmem/core.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
--- a/drivers/nvmem/core.c +++ b/drivers/nvmem/core.c @@ -83,7 +83,7 @@ static void nvmem_cell_drop(struct nvmem list_del(&cell->node); mutex_unlock(&nvmem_mutex); of_node_put(cell->np); - kfree(cell->name); + kfree_const(cell->name); kfree(cell); }
@@ -110,7 +110,9 @@ static int nvmem_cell_info_to_nvmem_cell cell->nvmem = nvmem; cell->offset = info->offset; cell->bytes = info->bytes; - cell->name = info->name; + cell->name = kstrdup_const(info->name, GFP_KERNEL); + if (!cell->name) + return -ENOMEM;
cell->bit_offset = info->bit_offset; cell->nbits = info->nbits; @@ -300,7 +302,7 @@ static int nvmem_add_cells_from_of(struc dev_err(dev, "cell %s unaligned to nvmem stride %d\n", cell->name, nvmem->stride); /* Cells already added will be freed later. */ - kfree(cell->name); + kfree_const(cell->name); kfree(cell); return -EINVAL; }