AZL-93461

In the Linux kernel, the following vulnerability has been resolved:

netfilter: ebtables: terminate table name before findtablelock()

updatecounters() and compatupdatecounters() forward a user-supplied 32-byte table name to findtablelock() without NUL-terminating it. On a lookup miss, findinlistlock() calls trythenrequestmodule(..., "%s%s", "ebtable_", name), and vsnprintf() reads past the name field and the stack object until it hits a zero byte.

BUG: KASAN: stack-out-of-bounds in string (lib/vsprintf.c:648 lib/vsprintf.c:730) Read of size 1 at addr ffff8880119dfb20 by task exploit/147 Call Trace: ... string (lib/vsprintf.c:648 lib/vsprintf.c:730) vsnprintf (lib/vsprintf.c:2945) __requestmodule (kernel/module/kmod.c:150) doupdatecounters.isra.0 (net/bridge/netfilter/ebtables.c:371 net/bridge/netfilter/ebtables.c:380) updatecounters (net/bridge/netfilter/ebtables.c:1440) doebtsetctl (net/bridge/netfilter/ebtables.c:2573) nfsetsockopt (net/netfilter/nfsockopt.c:101) ipsetsockopt (net/ipv4/ipsockglue.c:1424) rawsetsockopt (net/ipv4/raw.c:847) _syssetsockopt (net/socket.c:2393) ...

compatdoreplace() shares the same unterminated name via compatcopyebtreplacefromuser(); terminate it there too so all findtable_lock() callers behave alike. The other callers already terminate the name after the copy.