[PATCH 05/14] netfilter: ebtables: convert BUG_ONs to WARN_ONs

[Pablo Neira Ayuso]

From: Florian Westphal <f...@strlen.de>

All of these conditions are not fatal and should have
been WARN_ONs from the get-go.

Convert them to WARN_ONs and bail out.

Signed-off-by: Florian Westphal <f...@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pa...@netfilter.org>
---
 net/bridge/netfilter/ebtables.c | 27 ++++++++++++++++++---------
 1 file changed, 18 insertions(+), 9 deletions(-)

diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index 02c4b409d317..61f87879e389 100644
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -1641,7 +1641,8 @@ static int compat_match_to_user(struct ebt_entry_match 
*m, void __user **dstptr,
        int off = ebt_compat_match_offset(match, m->match_size);
        compat_uint_t msize = m->match_size - off;
 
-       BUG_ON(off >= m->match_size);
+       if (WARN_ON(off >= m->match_size))
+               return -EINVAL;
 
        if (copy_to_user(cm->u.name, match->name,
            strlen(match->name) + 1) || put_user(msize, &cm->match_size))
@@ -1671,7 +1672,8 @@ static int compat_target_to_user(struct ebt_entry_target 
*t,
        int off = xt_compat_target_offset(target);
        compat_uint_t tsize = t->target_size - off;
 
-       BUG_ON(off >= t->target_size);
+       if (WARN_ON(off >= t->target_size))
+               return -EINVAL;
 
        if (copy_to_user(cm->u.name, target->name,
            strlen(target->name) + 1) || put_user(tsize, &cm->match_size))
@@ -1902,7 +1904,8 @@ static int ebt_buf_add(struct ebt_entries_buf_state 
*state,
        if (state->buf_kern_start == NULL)
                goto count_only;
 
-       BUG_ON(state->buf_kern_offset + sz > state->buf_kern_len);
+       if (WARN_ON(state->buf_kern_offset + sz > state->buf_kern_len))
+               return -EINVAL;
 
        memcpy(state->buf_kern_start + state->buf_kern_offset, data, sz);
 
@@ -1915,7 +1918,8 @@ static int ebt_buf_add_pad(struct ebt_entries_buf_state 
*state, unsigned int sz)
 {
        char *b = state->buf_kern_start;
 
-       BUG_ON(b && state->buf_kern_offset > state->buf_kern_len);
+       if (WARN_ON(b && state->buf_kern_offset > state->buf_kern_len))
+               return -EINVAL;
 
        if (b != NULL && sz > 0)
                memset(b + state->buf_kern_offset, 0, sz);
@@ -1992,8 +1996,10 @@ static int compat_mtw_from_user(struct 
compat_ebt_entry_mwt *mwt,
        pad = XT_ALIGN(size_kern) - size_kern;
 
        if (pad > 0 && dst) {
-               BUG_ON(state->buf_kern_len <= pad);
-               BUG_ON(state->buf_kern_offset - (match_size + off) + size_kern 
> state->buf_kern_len - pad);
+               if (WARN_ON(state->buf_kern_len <= pad))
+                       return -EINVAL;
+               if (WARN_ON(state->buf_kern_offset - (match_size + off) + 
size_kern > state->buf_kern_len - pad))
+                       return -EINVAL;
                memset(dst + size_kern, 0, pad);
        }
        return off + match_size;
@@ -2043,7 +2049,8 @@ static int ebt_size_mwt(struct compat_ebt_entry_mwt 
*match32,
                if (ret < 0)
                        return ret;
 
-               BUG_ON(ret < match32->match_size);
+               if (WARN_ON(ret < match32->match_size))
+                       return -EINVAL;
                growth += ret - match32->match_size;
                growth += ebt_compat_entry_padsize();
 
@@ -2140,7 +2147,8 @@ static int size_entry_mwt(struct ebt_entry *entry, const 
unsigned char *base,
 
        startoff = state->buf_user_offset - startoff;
 
-       BUG_ON(*total < startoff);
+       if (WARN_ON(*total < startoff))
+               return -EINVAL;
        *total -= startoff;
        return 0;
 }
@@ -2267,7 +2275,8 @@ static int compat_do_replace(struct net *net, void __user 
*user,
        state.buf_kern_len = size64;
 
        ret = compat_copy_entries(entries_tmp, tmp.entries_size, &state);
-       BUG_ON(ret < 0);        /* parses same data again */
+       if (WARN_ON(ret < 0))
+               goto out_unlock;
 
        vfree(entries_tmp);
        tmp.entries_size = size64;
-- 
2.11.0