cb74d8b8f0
Fix the sockaddr length verification in the connect() handler of NFC/LLCP sockets, to compare against the size of the actual structure expected on input (sockaddr_nfc_llcp) instead of its shorter version (sockaddr_nfc). Both structures are defined in include/uapi/linux/nfc.h. The fields specific to the _llcp extended struct are as follows: 276 __u8 dsap; /* Destination SAP, if known */ 277 __u8 ssap; /* Source SAP to be bound to */ 278 char service_name[NFC_LLCP_MAX_SERVICE_NAME]; /* Service name URI */; 279 size_t service_name_len; If the caller doesn't provide a sufficiently long sockaddr buffer, these fields remain uninitialized (and they currently originate from the stack frame of the top-level sys_connect handler). They are then copied by llcp_sock_connect() into internal storage (nfc_llcp_sock structure), and could be subsequently read back through the user-mode getsockname() function (handled by llcp_sock_getname()). This would result in the disclosure of up to ~70 uninitialized bytes from the kernel stack to user-mode clients capable of creating AFC_NFC sockets. Change-Id: I56398a2edac9496001d1f96b4e625b55ca0b9934 Signed-off-by: Mateusz Jurczyk <mjurczyk@google.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com> Signed-off-by: Kevin F. Haggerty <haggertk@lineageos.org> |
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| .. | ||
| llcp | ||
| nci | ||
| Kconfig | ||
| Makefile | ||
| af_nfc.c | ||
| core.c | ||
| netlink.c | ||
| nfc.h | ||
| rawsock.c | ||