check_fwfile_format() reads each block header and trusts its data length before proving that both fit in the firmware image. A truncated header or oversized block can therefore pass malformed extents to the download path. Require the remaining image to contain the complete header and payload before accepting each block. Fixes: c305a19a0d0a ("libertas_tf: usb specific functions") Signed-off-by: Pengpeng Hou --- drivers/net/wireless/marvell/libertas_tf/if_usb.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/marvell/libertas_tf/if_usb.c b/drivers/net/wireless/marvell/libertas_tf/if_usb.c index b85c6d783bf7b..b9d1a33bddfce 100644 --- a/drivers/net/wireless/marvell/libertas_tf/if_usb.c +++ b/drivers/net/wireless/marvell/libertas_tf/if_usb.c @@ -769,10 +769,18 @@ static int check_fwfile_format(const u8 *data, u32 totlen) exit = len = 0; do { - struct fwheader *fwh = (void *) data; + struct fwheader *fwh; + + if (totlen - len < sizeof(*fwh)) + break; + + fwh = (void *)data; bincmd = le32_to_cpu(fwh->dnldcmd); blksize = le32_to_cpu(fwh->datalength); + if (blksize > totlen - len - sizeof(*fwh)) + break; + switch (bincmd) { case FW_HAS_DATA_TO_RECV: offset = sizeof(struct fwheader) + blksize; base-commit: 08dbfad3f5040f5bdb6c529da20d6d4e81fefd72 -- 2.50.1