diff options
| -rw-r--r-- | scripts/mod/file2alias.c | 79 |
1 files changed, 53 insertions, 26 deletions
diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c index 4e99393a35f1..2ad87a74bb03 100644 --- a/scripts/mod/file2alias.c +++ b/scripts/mod/file2alias.c @@ -651,7 +651,26 @@ static void do_vio_entry(struct module *mod, void *symval) module_alias_printf(mod, true, "%s", alias); } -static void do_input(char *alias, +static void __attribute__((format(printf, 3, 4))) +alias_append(char *alias, size_t size, const char *fmt, ...) +{ + size_t len = strlen(alias); + va_list args; + int n; + + if (len >= size) + fatal("alias buffer (%zu) overflow before append\n", size); + + va_start(args, fmt); + n = vsnprintf(alias + len, size - len, fmt, args); + va_end(args); + + if (n < 0 || (size_t)n >= size - len) + fatal("alias buffer (%zu) overflow on append (need %d, have %zu)\n", + size, n, size - len); +} + +static void do_input(char *alias, size_t size, kernel_ulong_t *arr, unsigned int min, unsigned int max) { unsigned int i; @@ -659,13 +678,14 @@ static void do_input(char *alias, for (i = min; i <= max; i++) if (get_unaligned_native(arr + i / BITS_PER_LONG) & (1ULL << (i % BITS_PER_LONG))) - sprintf(alias + strlen(alias), "%X,*", i); + alias_append(alias, size, "%X,*", i); } /* input:b0v0p0e0-eXkXrXaXmXlXsXfXwX where X is comma-separated %02X. */ static void do_input_entry(struct module *mod, void *symval) { char alias[256] = {}; + const size_t sizeof_alias = sizeof(alias); DEF_FIELD(symval, input_device_id, flags); DEF_FIELD(symval, input_device_id, bustype); @@ -687,35 +707,35 @@ static void do_input_entry(struct module *mod, void *symval) ADD(alias, "p", flags & INPUT_DEVICE_ID_MATCH_PRODUCT, product); ADD(alias, "e", flags & INPUT_DEVICE_ID_MATCH_VERSION, version); - sprintf(alias + strlen(alias), "-e*"); + alias_append(alias, sizeof_alias, "-e*"); if (flags & INPUT_DEVICE_ID_MATCH_EVBIT) - do_input(alias, *evbit, 0, INPUT_DEVICE_ID_EV_MAX); - sprintf(alias + strlen(alias), "k*"); + do_input(alias, sizeof_alias, *evbit, 0, INPUT_DEVICE_ID_EV_MAX); + alias_append(alias, sizeof_alias, "k*"); if (flags & INPUT_DEVICE_ID_MATCH_KEYBIT) - do_input(alias, *keybit, + do_input(alias, sizeof_alias, *keybit, INPUT_DEVICE_ID_KEY_MIN_INTERESTING, INPUT_DEVICE_ID_KEY_MAX); - sprintf(alias + strlen(alias), "r*"); + alias_append(alias, sizeof_alias, "r*"); if (flags & INPUT_DEVICE_ID_MATCH_RELBIT) - do_input(alias, *relbit, 0, INPUT_DEVICE_ID_REL_MAX); - sprintf(alias + strlen(alias), "a*"); + do_input(alias, sizeof_alias, *relbit, 0, INPUT_DEVICE_ID_REL_MAX); + alias_append(alias, sizeof_alias, "a*"); if (flags & INPUT_DEVICE_ID_MATCH_ABSBIT) - do_input(alias, *absbit, 0, INPUT_DEVICE_ID_ABS_MAX); - sprintf(alias + strlen(alias), "m*"); + do_input(alias, sizeof_alias, *absbit, 0, INPUT_DEVICE_ID_ABS_MAX); + alias_append(alias, sizeof_alias, "m*"); if (flags & INPUT_DEVICE_ID_MATCH_MSCIT) - do_input(alias, *mscbit, 0, INPUT_DEVICE_ID_MSC_MAX); - sprintf(alias + strlen(alias), "l*"); + do_input(alias, sizeof_alias, *mscbit, 0, INPUT_DEVICE_ID_MSC_MAX); + alias_append(alias, sizeof_alias, "l*"); if (flags & INPUT_DEVICE_ID_MATCH_LEDBIT) - do_input(alias, *ledbit, 0, INPUT_DEVICE_ID_LED_MAX); - sprintf(alias + strlen(alias), "s*"); + do_input(alias, sizeof_alias, *ledbit, 0, INPUT_DEVICE_ID_LED_MAX); + alias_append(alias, sizeof_alias, "s*"); if (flags & INPUT_DEVICE_ID_MATCH_SNDBIT) - do_input(alias, *sndbit, 0, INPUT_DEVICE_ID_SND_MAX); - sprintf(alias + strlen(alias), "f*"); + do_input(alias, sizeof_alias, *sndbit, 0, INPUT_DEVICE_ID_SND_MAX); + alias_append(alias, sizeof_alias, "f*"); if (flags & INPUT_DEVICE_ID_MATCH_FFBIT) - do_input(alias, *ffbit, 0, INPUT_DEVICE_ID_FF_MAX); - sprintf(alias + strlen(alias), "w*"); + do_input(alias, sizeof_alias, *ffbit, 0, INPUT_DEVICE_ID_FF_MAX); + alias_append(alias, sizeof_alias, "w*"); if (flags & INPUT_DEVICE_ID_MATCH_SWBIT) - do_input(alias, *swbit, 0, INPUT_DEVICE_ID_SW_MAX); + do_input(alias, sizeof_alias, *swbit, 0, INPUT_DEVICE_ID_SW_MAX); module_alias_printf(mod, false, "input:%s", alias); } @@ -895,12 +915,16 @@ static const struct dmifield { { NULL, DMI_NONE } }; -static void dmi_ascii_filter(char *d, const char *s) +static void dmi_ascii_filter(char *d, size_t avail, const char *s) { /* Filter out characters we don't want to see in the modalias string */ for (; *s; s++) - if (*s > ' ' && *s < 127 && *s != ':') + if (*s > ' ' && *s < 127 && *s != ':') { + if (avail <= 1) + fatal("%s: alias buffer overflow\n", __func__); *(d++) = *s; + avail--; + } *d = 0; } @@ -909,6 +933,8 @@ static void dmi_ascii_filter(char *d, const char *s) static void do_dmi_entry(struct module *mod, void *symval) { char alias[256] = {}; + const size_t sizeof_alias = sizeof(alias); + size_t len; int i, j; DEF_FIELD_ADDR(symval, dmi_system_id, matches); @@ -916,11 +942,12 @@ static void do_dmi_entry(struct module *mod, void *symval) for (j = 0; j < 4; j++) { if ((*matches)[j].slot && (*matches)[j].slot == dmi_fields[i].field) { - sprintf(alias + strlen(alias), ":%s*", - dmi_fields[i].prefix); - dmi_ascii_filter(alias + strlen(alias), + alias_append(alias, sizeof_alias, ":%s*", + dmi_fields[i].prefix); + len = strlen(alias); + dmi_ascii_filter(alias + len, sizeof_alias - len, (*matches)[j].substr); - strcat(alias, "*"); + alias_append(alias, sizeof_alias, "*"); } } } |