From: Adrian Korwel Date: Mon, 25 May 2026 14:58:31 +0000 (-0500) Subject: USB: serial: io_ti: fix heap overflow in get_manuf_info() X-Git-Tag: v7.1~10^2~1^2~2 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=183c1076eca43bbb3e7bdf597456f91d81c73e74;p=thirdparty%2Flinux.git USB: serial: io_ti: fix heap overflow in get_manuf_info() get_manuf_info() reads le16_to_cpu(rom_desc->Size) bytes from the device I2C EEPROM into a buffer allocated with kmalloc_obj(), which is sizeof(struct edge_ti_manuf_descriptor) = 10 bytes. The Size field comes from the device and is only validated (in check_i2c_image()) to make sure the descriptor fits within TI_MAX_I2C_SIZE (16384 bytes), not against the destination buffer size. A malicious USB device can therefore set Size to any value up to 16377, causing a heap overflow of up to 16367 bytes when plugged into a host running this driver. valid_csum() is called after read_rom() and also iterates buffer[0..Size-1], compounding the out-of-bounds access. Fix by rejecting descriptors with unexpected length before calling read_rom(). Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Adrian Korwel [ johan: amend commit message; also check for short descriptors ] Signed-off-by: Johan Hovold --- diff --git a/drivers/usb/serial/io_ti.c b/drivers/usb/serial/io_ti.c index cb55370e036f7..6e0d4c38911b5 100644 --- a/drivers/usb/serial/io_ti.c +++ b/drivers/usb/serial/io_ti.c @@ -773,6 +773,12 @@ static int get_manuf_info(struct edgeport_serial *serial, u8 *buffer) } /* Read the descriptor data */ + if (le16_to_cpu(rom_desc->Size) != sizeof(struct edge_ti_manuf_descriptor)) { + dev_err(dev, "unexpected Edge descriptor length: %u\n", + le16_to_cpu(rom_desc->Size)); + status = -EINVAL; + goto exit; + } status = read_rom(serial, start_address+sizeof(struct ti_i2c_desc), le16_to_cpu(rom_desc->Size), buffer); if (status)