From e99dd0785ebcd597e7b3958ce7fd1f80da194104 Mon Sep 17 00:00:00 2001 From: Andrew Chant Date: Fri, 7 Apr 2017 10:58:26 -0700 Subject: [PATCH] input: synaptics_dsx: validate bounds of intr_reg_num Validate the intr_reg_num value returned by touchscreen to ensure no out of bounds access can occur. Bug: 35472278 Change-Id: I22f5b67815fe7d448b5ed847e4e3d65af63bed84 Signed-off-by: Andrew Chant Git-repo: https://android.googlesource.com/kernel/msm Git-commit: 271baca849983ef309e82a4e5953027790f36154 Signed-off-by: Dennis Cagle Signed-off-by: Shantanu Jain --- .../synaptics_dsx/synaptics_dsx_core.c | 31 +++++++++++++++---- 1 file changed, 25 insertions(+), 6 deletions(-) diff --git a/drivers/input/touchscreen/synaptics_dsx/synaptics_dsx_core.c b/drivers/input/touchscreen/synaptics_dsx/synaptics_dsx_core.c index daa35845fc0a..93c9c3c373b8 100644 --- a/drivers/input/touchscreen/synaptics_dsx/synaptics_dsx_core.c +++ b/drivers/input/touchscreen/synaptics_dsx/synaptics_dsx_core.c @@ -1495,7 +1495,7 @@ static int synaptics_rmi4_irq_enable(struct synaptics_rmi4_data *rmi4_data, return retval; } -static void synaptics_rmi4_set_intr_mask(struct synaptics_rmi4_fn *fhandler, +static int synaptics_rmi4_set_intr_mask(struct synaptics_rmi4_fn *fhandler, struct synaptics_rmi4_fn_desc *fd, unsigned int intr_count) { @@ -1503,6 +1503,12 @@ static void synaptics_rmi4_set_intr_mask(struct synaptics_rmi4_fn *fhandler, unsigned char intr_offset; fhandler->intr_reg_num = (intr_count + 7) / 8; + if (fhandler->intr_reg_num >= MAX_INTR_REGISTERS) { + fhandler->intr_reg_num = 0; + fhandler->num_of_data_sources = 0; + fhandler->intr_mask = 0; + return -EINVAL; + } if (fhandler->intr_reg_num != 0) fhandler->intr_reg_num -= 1; @@ -1515,7 +1521,7 @@ static void synaptics_rmi4_set_intr_mask(struct synaptics_rmi4_fn *fhandler, ii++) fhandler->intr_mask |= 1 << ii; - return; + return 0; } static int synaptics_rmi4_f01_init(struct synaptics_rmi4_data *rmi4_data, @@ -1523,12 +1529,17 @@ static int synaptics_rmi4_f01_init(struct synaptics_rmi4_data *rmi4_data, struct synaptics_rmi4_fn_desc *fd, unsigned int intr_count) { + int retval; + fhandler->fn_number = fd->fn_number; fhandler->num_of_data_sources = fd->intr_src_count; fhandler->data = NULL; fhandler->extra = NULL; - synaptics_rmi4_set_intr_mask(fhandler, fd, intr_count); + retval = synaptics_rmi4_set_intr_mask(fhandler, fd, intr_count); + if (retval < 0) + return retval; + rmi4_data->f01_query_base_addr = fd->query_base_addr; rmi4_data->f01_ctrl_base_addr = fd->ctrl_base_addr; @@ -1653,7 +1664,9 @@ static int synaptics_rmi4_f11_init(struct synaptics_rmi4_data *rmi4_data, if (retval < 0) return retval; - synaptics_rmi4_set_intr_mask(fhandler, fd, intr_count); + retval = synaptics_rmi4_set_intr_mask(fhandler, fd, intr_count); + if (retval < 0) + return retval; abs_data_size = query[5] & MASK_2BIT; abs_data_blk_size = 3 + (2 * (abs_data_size == 0 ? 1 : 0)); @@ -1934,7 +1947,9 @@ static int synaptics_rmi4_f12_init(struct synaptics_rmi4_data *rmi4_data, if (retval < 0) goto free_function_handler_mem; - synaptics_rmi4_set_intr_mask(fhandler, fd, intr_count); + retval = synaptics_rmi4_set_intr_mask(fhandler, fd, intr_count); + if (retval < 0) + return retval; /* Allocate memory for finger data storage space */ fhandler->data_size = num_of_fingers * size_of_2d_data; @@ -2092,7 +2107,9 @@ static int synaptics_rmi4_f1a_init(struct synaptics_rmi4_data *rmi4_data, fhandler->fn_number = fd->fn_number; fhandler->num_of_data_sources = fd->intr_src_count; - synaptics_rmi4_set_intr_mask(fhandler, fd, intr_count); + retval = synaptics_rmi4_set_intr_mask(fhandler, fd, intr_count); + if (retval < 0) + return retval; retval = synaptics_rmi4_f1a_alloc_mem(rmi4_data, fhandler); if (retval < 0) @@ -2491,6 +2508,8 @@ flash_prog_mode: dev_dbg(rmi4_data->pdev->dev.parent, "%s: Number of interrupt registers = %d\n", __func__, rmi4_data->num_of_intr_regs); + if (rmi4_data->num_of_intr_regs >= MAX_INTR_REGISTERS) + return -EINVAL; retval = synaptics_rmi4_reg_read(rmi4_data, rmi4_data->f01_query_base_addr,