netfilter: x_tables: add and use xt_check_proc_name

recent and hashlimit both create /proc files, but only check that
name is 0 terminated.

This can trigger WARN() from procfs when name is "" or "/".
Add helper for this and then use it for both.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Reported-by: <syzbot+0502b00edac2a0680b61@syzkaller.appspotmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Florian Westphal 2018-03-10 01:15:45 +01:00 committed by Pablo Neira Ayuso
parent 932909d9b2
commit b1d0a5d0cb
4 changed files with 45 additions and 9 deletions

View file

@ -285,6 +285,8 @@ unsigned int *xt_alloc_entry_offsets(unsigned int size);
bool xt_find_jump_offset(const unsigned int *offsets,
unsigned int target, unsigned int size);
int xt_check_proc_name(const char *name, unsigned int size);
int xt_check_match(struct xt_mtchk_param *, unsigned int size, u_int8_t proto,
bool inv_proto);
int xt_check_target(struct xt_tgchk_param *, unsigned int size, u_int8_t proto,