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Thus lets use strscpy() helper instead. Same time make all get_modalias() callers to handler error. CC: Jean Delvare Signed-off-by: Cyrill Gorcunov --- v2: - add comment about reserving space for suffix - check for error in callers drivers/firmware/dmi-id.c | 30 +++++++++++++++++++----------- 1 file changed, 19 insertions(+), 11 deletions(-) Index: linux-tip.git/drivers/firmware/dmi-id.c =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D --- linux-tip.git.orig/drivers/firmware/dmi-id.c +++ linux-tip.git/drivers/firmware/dmi-id.c @@ -103,8 +103,15 @@ static ssize_t get_modalias(char *buffer char *p; const struct mafield *f; =20 - strcpy(buffer, "dmi"); - p =3D buffer + 3; left =3D buffer_size - 4; + l =3D strscpy(buffer, "dmi", buffer_size); + if (l < 0) + return -ENOMEM; + p =3D buffer + l; + + /* Reserve place for suffix */ + left =3D buffer_size - l - 1; + if (left < 0) + return -ENOMEM; =20 for (f =3D fields; f->prefix && left > 0; f++) { const char *c; @@ -125,20 +132,21 @@ static ssize_t get_modalias(char *buffer left -=3D l; } =20 - p[0] =3D ':'; - p[1] =3D 0; + *p++ =3D ':'; + *p =3D 0; =20 - return p - buffer + 1; + return p - buffer; } =20 static ssize_t sys_dmi_modalias_show(struct device *dev, struct device_attribute *attr, char *page) { - ssize_t r; - r =3D get_modalias(page, PAGE_SIZE-1); - page[r] =3D '\n'; - page[r+1] =3D 0; - return r+1; + ssize_t r =3D get_modalias(page, PAGE_SIZE-1); + if (r > 0) { + page[r++] =3D '\n'; + page[r] =3D 0; + } + return r; } =20 static struct device_attribute sys_dmi_modalias_attr =3D @@ -163,7 +171,7 @@ static int dmi_dev_uevent(const struct d return -ENOMEM; len =3D get_modalias(&env->buf[env->buflen - 1], sizeof(env->buf) - env->buflen); - if (len >=3D (sizeof(env->buf) - env->buflen)) + if (len < 0) return -ENOMEM; env->buflen +=3D len; return 0;