staging: rtl8723bs: fix OOB reads in rtw_get_sec_ie(), rtw_get_wapi_ie(), and rtw_get...

staging: rtl8723bs: fix OOB reads in rtw_get_sec_ie(), rtw_get_wapi_ie(), and rtw_get_wps_attr()

Three IE/attribute parsing functions have missing bounds checks.

rtw_get_sec_ie() and rtw_get_wapi_ie() iterate over a raw IE buffer
without verifying that the header bytes (tag + length) are within the
remaining buffer before reading them.  Additionally, rtw_get_sec_ie()
compares the 4-byte WPA OUI at cnt+2 without checking that at least
6 bytes remain, and rtw_get_wapi_ie() compares a 4-byte WAPI OUI at
cnt+6 without checking that at least 10 bytes remain.

rtw_get_wps_attr() reads wps_ie[0] and wps_ie+2 unconditionally at
entry, before verifying that wps_ielen is large enough to contain
the 6-byte WPS IE header (element_id + length + 4-byte OUI).  Inside
the attribute loop, get_unaligned_be16() is called on attr_ptr and
attr_ptr+2 without checking that 4 bytes remain in the buffer.

Add a cnt+2 bounds check before each loop body in rtw_get_sec_ie()
and rtw_get_wapi_ie(), guard each multi-byte comparison with a minimum
IE length requirement, add a wps_ielen < 6 early return in
rtw_get_wps_attr(), and add a 4-byte bounds check in its inner loop.

Fixes: 554c0a3abf21 ("staging: Add rtl8723bs sdio wifi driver")
Cc: stable <stable@kernel.org>
Signed-off-by: Alexandru Hossu <hossu.alexandru@gmail.com>
Link: https://patch.msgid.link/20260522004531.1038924-8-hossu.alexandru@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>