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: 954ee164f4f4 ("[PATCH] libertas: reorganize and simplify init sequence") Signed-off-by: Pengpeng Hou --- drivers/net/wireless/marvell/libertas/if_usb.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/marvell/libertas/if_usb.c b/drivers/net/wireless/marvell/libertas/if_usb.c index 5cc0c5cac2574..74870c9bd091c 100644 --- a/drivers/net/wireless/marvell/libertas/if_usb.c +++ b/drivers/net/wireless/marvell/libertas/if_usb.c @@ -798,10 +798,18 @@ static int check_fwfile_format(const uint8_t *data, uint32_t 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