From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.92 #3 (Red Hat Linux)) id 1hslkC-0000gQ-It for barebox@lists.infradead.org; Wed, 31 Jul 2019 10:22:06 +0000 From: Ahmad Fatoum Date: Wed, 31 Jul 2019 12:21:43 +0200 Message-Id: <20190731102143.20503-3-a.fatoum@pengutronix.de> In-Reply-To: <20190731102143.20503-1-a.fatoum@pengutronix.de> References: <20190731102143.20503-1-a.fatoum@pengutronix.de> MIME-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: [PATCH v2 3/3] console: fix out-of-bounds read in dputc(/dev/*, ...) To: barebox@lists.infradead.org Cc: Ahmad Fatoum , Bastian Krause Trying to output a single character via echo -a /dev/serial0-1 currently results in garbage output after the newline, because console.c's fops_write discards the buffer length and passes the buffer to (struct cdev)::puts which only handles NUL-terminated strings. Fix this by amending (struct cdev)::puts with a new nbytes parameter, which is correctly propagated. Fixes: b4f55fcf35 ("console: expose consoles in devfs") Cc: Bastian Krause Signed-off-by: Ahmad Fatoum --- Changes in v2: - fixed commit hash in Fixes:, by Bastian - fixed possible incomplete writes in __console_puts - rebased on top of two potential bug fixes --- common/console.c | 14 +++++++------- common/ratp/ratp.c | 10 ++++------ drivers/serial/efi-stdio.c | 5 +++-- drivers/serial/serial_efi.c | 5 +++-- fs/pstore/platform.c | 7 ++++--- include/console.h | 2 +- 6 files changed, 22 insertions(+), 21 deletions(-) diff --git a/common/console.c b/common/console.c index 52162df23b04..ce4122fa76f1 100644 --- a/common/console.c +++ b/common/console.c @@ -253,19 +253,19 @@ static void console_set_stdoutpath(struct console_device *cdev) free(str); } -static int __console_puts(struct console_device *cdev, const char *s) +static int __console_puts(struct console_device *cdev, const char *s, + size_t nbytes) { - int n = 0; + size_t i; - while (*s) { + for (i = 0; i < nbytes; i++) { if (*s == '\n') cdev->putc(cdev, '\r'); cdev->putc(cdev, *s); - n++; s++; } - return n; + return i; } static int fops_open(struct cdev *cdev, unsigned long flags) @@ -297,7 +297,7 @@ static ssize_t fops_write(struct cdev* dev, const void* buf, size_t count, { struct console_device *priv = dev->priv; - priv->puts(priv, buf); + priv->puts(priv, buf, count); return 0; } @@ -544,7 +544,7 @@ int console_puts(unsigned int ch, const char *str) if (initialized == CONSOLE_INIT_FULL) { for_each_console(cdev) { if (cdev->f_active & ch) { - n = cdev->puts(cdev, str); + n = cdev->puts(cdev, str, strlen(str)); } } return n; diff --git a/common/ratp/ratp.c b/common/ratp/ratp.c index 8ac7dc98b6f8..8f989515e485 100644 --- a/common/ratp/ratp.c +++ b/common/ratp/ratp.c @@ -259,19 +259,17 @@ static int ratp_console_tstc(struct console_device *cdev) return kfifo_len(ctx->console_recv_fifo) ? 1 : 0; } -static int ratp_console_puts(struct console_device *cdev, const char *s) +static int ratp_console_puts(struct console_device *cdev, const char *s, + size_t nbytes) { struct ratp_ctx *ctx = container_of(cdev, struct ratp_ctx, ratp_console); - int len = 0; - - len = strlen(s); if (ratp_busy(&ctx->ratp)) return 0; - kfifo_put(ctx->console_transmit_fifo, s, len); + kfifo_put(ctx->console_transmit_fifo, s, nbytes); - return len; + return nbytes; } static void ratp_console_putc(struct console_device *cdev, char c) diff --git a/drivers/serial/efi-stdio.c b/drivers/serial/efi-stdio.c index 0703f727e766..2ca89fa4f861 100644 --- a/drivers/serial/efi-stdio.c +++ b/drivers/serial/efi-stdio.c @@ -243,12 +243,13 @@ static int efi_process_key(struct efi_console_priv *priv, const char *inp) return 1; } -static int efi_console_puts(struct console_device *cdev, const char *s) +static int efi_console_puts(struct console_device *cdev, const char *s, + size_t nbytes) { struct efi_console_priv *priv = to_efi(cdev); int n = 0; - while (*s) { + while (nbytes--) { if (*s == 27) { priv->efi_console_buffer[n] = 0; priv->out->output_string(priv->out, diff --git a/drivers/serial/serial_efi.c b/drivers/serial/serial_efi.c index f0a2b22c2bc2..667d51f622ec 100644 --- a/drivers/serial/serial_efi.c +++ b/drivers/serial/serial_efi.c @@ -130,13 +130,14 @@ static void efi_serial_putc(struct console_device *cdev, char c) serial->write(serial, &buffersize, &c); } -static int efi_serial_puts(struct console_device *cdev, const char *s) +static int efi_serial_puts(struct console_device *cdev, const char *s, + size_t nbytes) { struct efi_serial_port *uart = to_efi_serial_port(cdev); struct efi_serial_io_protocol *serial = uart->serial; uint32_t control; efi_status_t efiret; - unsigned long buffersize = strlen(s) * sizeof(char); + unsigned long buffersize = nbytes; do { efiret = serial->getcontrol(serial, &control); diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index 755363c30999..601bfca6b025 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -67,10 +67,11 @@ static void pstore_console_write(const char *s, unsigned c) } } -static int pstore_console_puts(struct console_device *cdev, const char *s) +static int pstore_console_puts(struct console_device *cdev, const char *s, + size_t nbytes) { - pstore_console_write(s, strlen(s)); - return strlen(s); + pstore_console_write(s, nbytes); + return nbytes; } static void pstore_console_putc(struct console_device *cdev, char c) diff --git a/include/console.h b/include/console.h index 673921331db7..1d86a584a7f2 100644 --- a/include/console.h +++ b/include/console.h @@ -42,7 +42,7 @@ struct console_device { int (*tstc)(struct console_device *cdev); void (*putc)(struct console_device *cdev, char c); - int (*puts)(struct console_device *cdev, const char *s); + int (*puts)(struct console_device *cdev, const char *s, size_t nbytes); int (*getc)(struct console_device *cdev); int (*setbrg)(struct console_device *cdev, int baudrate); void (*flush)(struct console_device *cdev); -- 2.20.1 _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox