[PATCH 3.16 136/245] netfilter: ebtables: convert BUG_ONs to WARN_ONs

Ben Hutchings
2020-04-23T23:16:30Z

From: Florian Westphal <fw@strlen.de>

commit fc6a5d0601c5ac1d02f283a46f60b87b2033e5ca upstream.

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 <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
net/bridge/netfilter/ebtables.c | 27 ++++++++++++++++++---------
1 file changed, 18 insertions(+), 9 deletions(-)

--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -1603,7 +1603,8 @@ static int compat_match_to_user(struct e
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))
@@ -1630,7 +1631,8 @@ static int compat_target_to_user(struct
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))
@@ -1858,7 +1860,8 @@ static int ebt_buf_add(struct ebt_entrie
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);

@@ -1871,7 +1874,8 @@ static int ebt_buf_add_pad(struct ebt_en
{
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);
@@ -1949,8 +1953,10 @@ static int compat_mtw_from_user(struct c
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;
@@ -2001,7 +2007,8 @@ static int ebt_size_mwt(struct compat_eb
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();

@@ -2116,7 +2123,8 @@ static int size_entry_mwt(struct ebt_ent

startoff = state->buf_user_offset - startoff;

- BUG_ON(*total < startoff);
+ if (WARN_ON(*total < startoff))
+ return -EINVAL;
*total -= startoff;
return 0;
}
@@ -2246,7 +2254,8 @@ static int compat_do_replace(struct net
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;