From: Dmitry Torokhov Date: Sun, 2 Apr 2006 05:09:51 +0000 (-0500) Subject: Input: make modalias code respect allowed buffer size X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=ac648a6a704f73cc2a0f128d9deeb57aa6d76f6d;p=linux-beck.git Input: make modalias code respect allowed buffer size Signed-off-by: Dmitry Torokhov --- diff --git a/drivers/input/input.c b/drivers/input/input.c index db52ba0a316f..a935abeffffc 100644 --- a/drivers/input/input.c +++ b/drivers/input/input.c @@ -571,15 +571,16 @@ INPUT_DEV_STRING_ATTR_SHOW(name); INPUT_DEV_STRING_ATTR_SHOW(phys); INPUT_DEV_STRING_ATTR_SHOW(uniq); -static int print_modalias_bits(char *buf, int size, char prefix, unsigned long *arr, - unsigned int min, unsigned int max) +static int input_print_modalias_bits(char *buf, int size, + char name, unsigned long *bm, + unsigned int min_bit, unsigned int max_bit) { - int len, i; + int len = 0, i; - len = snprintf(buf, size, "%c", prefix); - for (i = min; i < max; i++) - if (arr[LONG(i)] & BIT(i)) - len += snprintf(buf + len, size - len, "%X,", i); + len += snprintf(buf, max(size, 0), "%c", name); + for (i = min_bit; i < max_bit; i++) + if (bm[LONG(i)] & BIT(i)) + len += snprintf(buf + len, max(size - len, 0), "%X,", i); return len; } @@ -588,33 +589,32 @@ static int input_print_modalias(char *buf, int size, struct input_dev *id, { int len; - len = snprintf(buf, size, "input:b%04Xv%04Xp%04Xe%04X-", - id->id.bustype, - id->id.vendor, - id->id.product, - id->id.version); - - len += print_modalias_bits(buf + len, size - len, 'e', id->evbit, - 0, EV_MAX); - len += print_modalias_bits(buf + len, size - len, 'k', id->keybit, - KEY_MIN_INTERESTING, KEY_MAX); - len += print_modalias_bits(buf + len, size - len, 'r', id->relbit, - 0, REL_MAX); - len += print_modalias_bits(buf + len, size - len, 'a', id->absbit, - 0, ABS_MAX); - len += print_modalias_bits(buf + len, size - len, 'm', id->mscbit, - 0, MSC_MAX); - len += print_modalias_bits(buf + len, size - len, 'l', id->ledbit, - 0, LED_MAX); - len += print_modalias_bits(buf + len, size - len, 's', id->sndbit, - 0, SND_MAX); - len += print_modalias_bits(buf + len, size - len, 'f', id->ffbit, - 0, FF_MAX); - len += print_modalias_bits(buf + len, size - len, 'w', id->swbit, - 0, SW_MAX); + len = snprintf(buf, max(size, 0), + "input:b%04Xv%04Xp%04Xe%04X-", + id->id.bustype, id->id.vendor, + id->id.product, id->id.version); + + len += input_print_modalias_bits(buf + len, size - len, + 'e', id->evbit, 0, EV_MAX); + len += input_print_modalias_bits(buf + len, size - len, + 'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX); + len += input_print_modalias_bits(buf + len, size - len, + 'r', id->relbit, 0, REL_MAX); + len += input_print_modalias_bits(buf + len, size - len, + 'a', id->absbit, 0, ABS_MAX); + len += input_print_modalias_bits(buf + len, size - len, + 'm', id->mscbit, 0, MSC_MAX); + len += input_print_modalias_bits(buf + len, size - len, + 'l', id->ledbit, 0, LED_MAX); + len += input_print_modalias_bits(buf + len, size - len, + 's', id->sndbit, 0, SND_MAX); + len += input_print_modalias_bits(buf + len, size - len, + 'f', id->ffbit, 0, FF_MAX); + len += input_print_modalias_bits(buf + len, size - len, + 'w', id->swbit, 0, SW_MAX); if (add_cr) - len += snprintf(buf + len, size - len, "\n"); + len += snprintf(buf + len, max(size - len, 0), "\n"); return len; } @@ -739,8 +739,8 @@ static void input_dev_release(struct class_device *class_dev) * device bitfields. */ static int input_add_uevent_bm_var(char **envp, int num_envp, int *cur_index, - char *buffer, int buffer_size, int *cur_len, - const char *name, unsigned long *bitmap, int max) + char *buffer, int buffer_size, int *cur_len, + const char *name, unsigned long *bitmap, int max) { if (*cur_index >= num_envp - 1) return -ENOMEM; @@ -748,7 +748,7 @@ static int input_add_uevent_bm_var(char **envp, int num_envp, int *cur_index, envp[*cur_index] = buffer + *cur_len; *cur_len += snprintf(buffer + *cur_len, max(buffer_size - *cur_len, 0), name); - if (*cur_len > buffer_size) + if (*cur_len >= buffer_size) return -ENOMEM; *cur_len += input_print_bitmap(buffer + *cur_len, @@ -761,9 +761,33 @@ static int input_add_uevent_bm_var(char **envp, int num_envp, int *cur_index, return 0; } +static int input_add_uevent_modalias_var(char **envp, int num_envp, int *cur_index, + char *buffer, int buffer_size, int *cur_len, + struct input_dev *dev) +{ + if (*cur_index >= num_envp - 1) + return -ENOMEM; + + envp[*cur_index] = buffer + *cur_len; + + *cur_len += snprintf(buffer + *cur_len, max(buffer_size - *cur_len, 0), + "MODALIAS="); + if (*cur_len >= buffer_size) + return -ENOMEM; + + *cur_len += input_print_modalias(buffer + *cur_len, + max(buffer_size - *cur_len, 0), + dev, 0) + 1; + if (*cur_len > buffer_size) + return -ENOMEM; + + (*cur_index)++; + return 0; +} + #define INPUT_ADD_HOTPLUG_VAR(fmt, val...) \ do { \ - int err = add_uevent_var(envp, num_envp, &i, \ + int err = add_uevent_var(envp, num_envp, &i, \ buffer, buffer_size, &len, \ fmt, val); \ if (err) \ @@ -779,6 +803,16 @@ static int input_add_uevent_bm_var(char **envp, int num_envp, int *cur_index, return err; \ } while (0) +#define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev) \ + do { \ + int err = input_add_uevent_modalias_var(envp, \ + num_envp, &i, \ + buffer, buffer_size, &len, \ + dev); \ + if (err) \ + return err; \ + } while (0) + static int input_dev_uevent(struct class_device *cdev, char **envp, int num_envp, char *buffer, int buffer_size) { @@ -814,9 +848,7 @@ static int input_dev_uevent(struct class_device *cdev, char **envp, if (test_bit(EV_SW, dev->evbit)) INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX); - envp[i++] = buffer + len; - len += snprintf(buffer + len, buffer_size - len, "MODALIAS="); - len += input_print_modalias(buffer + len, buffer_size - len, dev, 0) + 1; + INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev); envp[i] = NULL; return 0;