From: Florian Westphal <fwestphal@xxxxxxxxxx>
Main code for 32 bit userland ebtables binary with 64 bit kernels
support.
Tested on x86_64 kernel only, using 64bit ebtables binary
for output comparision.
At least ebt_mark, m_mark and ebt_limit need CONFIG_COMPAT hooks, too.
remaining problem:
The ebtables userland makefile has:
ifeq ($(shell uname -m),sparc64)
CFLAGS+=-DEBT_MIN_ALIGN=8 -DKERNEL_64_USERSPACE_32
endif
struct ebt_replace, ebt_entry_match etc. then contain userland-side
padding, i.e. even if we are called from a 32 bit userland, the
structures may already be in the right format.
This problem is addressed in a follow-up patch.
Signed-off-by: Florian Westphal <fwestphal@xxxxxxxxxx>
---
net/bridge/netfilter/ebtables.c | 887 ++++++++++++++++++++++++++++++++++++++-
1 files changed, 886 insertions(+), 1 deletions(-)
diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index 76b99d3..fcaefdd 100644
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -51,11 +51,37 @@
static DEFINE_MUTEX(ebt_mutex);
+#ifdef CONFIG_COMPAT
+static void ebt_standard_compat_from_user(void *dst, const void *src)
+{
+ int v = *(compat_int_t *)src;
+
+ if (v >= 0)
+ v += xt_compat_calc_jump(NFPROTO_BRIDGE, v);
+ memcpy(dst, &v, sizeof(v));
+}
+
+static int ebt_standard_compat_to_user(void __user *dst, const void *src)
+{
+ compat_int_t cv = *(int *)src;
+
+ if (cv >= 0)
+ cv -= xt_compat_calc_jump(NFPROTO_BRIDGE, cv);
+ return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0;
+}
+#endif
+
+
static struct xt_target ebt_standard_target = {
.name = "standard",
.revision = 0,
.family = NFPROTO_BRIDGE,
.targetsize = sizeof(int),
+#ifdef CONFIG_COMPAT
+ .compatsize = sizeof(compat_int_t),
+ .compat_from_user = ebt_standard_compat_from_user,
+ .compat_to_user = ebt_standard_compat_to_user,
+#endif
};
static inline int
@@ -1454,7 +1480,7 @@ static int do_ebt_set_ctl(struct sock *sk,
break;
default:
ret = -EINVAL;
- }
+ }
return ret;
}
@@ -1514,15 +1540,874 @@ static int do_ebt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
return ret;
}
+#ifdef CONFIG_COMPAT
+/* 32 bit-userspace compatibility definitions. */
+struct compat_ebt_replace {
+ char name[EBT_TABLE_MAXNAMELEN];
+ compat_uint_t valid_hooks;
+ compat_uint_t nentries;
+ compat_uint_t entries_size;
+ /* start of the chains */
+ compat_uptr_t hook_entry[NF_BR_NUMHOOKS];
+ /* nr of counters userspace expects back */
+ compat_uint_t num_counters;
+ /* where the kernel will put the old counters. */
+ compat_uptr_t counters;
+ compat_uptr_t entries;
+};
+
+/* struct ebt_entry_match, _target and _watcher have same layout */
+struct compat_ebt_entry_mwt {
+ union {
+ char name[EBT_FUNCTION_MAXNAMELEN];
+ compat_uptr_t ptr;
+ } u;
+ compat_uint_t match_size;
+ compat_uint_t data[0];
+};
+
+/* account for possible padding between match_size and ->data */
+static int ebt_compat_entry_padsize(void)
+{
+ BUILD_BUG_ON(XT_ALIGN(sizeof(struct ebt_entry_match)) <
+ COMPAT_XT_ALIGN(sizeof(struct compat_ebt_entry_mwt)));
+ return (int) XT_ALIGN(sizeof(struct ebt_entry_match)) -
+ COMPAT_XT_ALIGN(sizeof(struct compat_ebt_entry_mwt));
+}
+
+static int ebt_compat_match_offset(const struct xt_match *match,
+ unsigned int userlen)
+{
+ /*
+ * ebt_among needs special handling. The kernel .matchsize is
+ * set to -1 at registration time; at runtime an EBT_ALIGN()ed
+ * value is expected.
+ * Example: userspace sends 4500, ebt_among.c wants 4504.
+ */
+ if (unlikely(match->matchsize == -1))
+ return XT_ALIGN(userlen) - COMPAT_XT_ALIGN(userlen);
+ return xt_compat_match_offset(match);
+}
+
+static int compat_match_to_user(struct ebt_entry_match *m, void __user **dstptr,
+ unsigned int *size)
+{
+ const struct xt_match *match = m->u.match;
+ struct compat_ebt_entry_mwt __user *cm = *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 (copy_to_user(cm->u.name, match->name,
+ strlen(match->name) + 1) || put_user(msize, &cm->match_size))
+ return -EFAULT;
+
+ if (match->compat_to_user) {
+ if (match->compat_to_user(cm->data, m->data))
+ return -EFAULT;
+ } else if (copy_to_user(cm->data, m->data, msize))
+ return -EFAULT;
+
+ *size -= ebt_compat_entry_padsize() + off;
+ *dstptr = cm->data;
+ *dstptr += msize;
+ return 0;
+}
+
+static int compat_target_to_user(struct ebt_entry_target *t,
+ void __user **dstptr,
+ unsigned int *size)
+{
+ const struct xt_target *target = t->u.target;
+ struct compat_ebt_entry_mwt __user *cm = *dstptr;
+ int off = xt_compat_target_offset(target);
+ compat_uint_t tsize = t->target_size - off;
+
+ BUG_ON(off >= t->target_size);
+
+ if (copy_to_user(cm->u.name, target->name,
+ strlen(target->name) + 1) || put_user(tsize, &cm->match_size))
+ return -EFAULT;
+
+ if (target->compat_to_user) {
+ if (target->compat_to_user(cm->data, t->data))
+ return -EFAULT;
+ } else if (copy_to_user(cm->data, t->data, tsize))
+ return -EFAULT;
+
+ *size -= ebt_compat_entry_padsize() + off;
+ *dstptr = cm->data;
+ *dstptr += tsize;
+ return 0;
+}
+
+static int compat_watcher_to_user(struct ebt_entry_watcher *w,
+ void __user **dstptr,
+ unsigned int *size)
+{
+ return compat_target_to_user((struct ebt_entry_target *)w,
+ dstptr, size);
+}
+
+static int compat_copy_entry_to_user(struct ebt_entry *e, void __user **dstptr,
+ unsigned int *size)
+{
+ struct ebt_entry_target *t;
+ struct ebt_entry __user *ce;
+ u32 watchers_offset, target_offset, next_offset;
+ compat_uint_t origsize;
+ int ret;
+
+ if (e->bitmask == 0) {
+ if (*size < sizeof(struct ebt_entries))
+ return -EINVAL;
+ if (copy_to_user(*dstptr, e, sizeof(struct ebt_entries)))
+ return -EFAULT;
+
+ *dstptr += sizeof(struct ebt_entries);
+ *size -= sizeof(struct ebt_entries);
+ return 0;
+ }
+
+ if (*size < sizeof(*ce))
+ return -EINVAL;
+
+ ce = (struct ebt_entry __user *)*dstptr;
+ if (copy_to_user(ce, e, sizeof(*ce)))
+ return -EFAULT;
+
+ origsize = *size;
+ *dstptr += sizeof(*ce);
+
+ ret = EBT_MATCH_ITERATE(e, compat_match_to_user, dstptr, size);
+ if (ret)
+ return ret;
+ watchers_offset = e->watchers_offset - (origsize - *size);
+
+ ret = EBT_WATCHER_ITERATE(e, compat_watcher_to_user, dstptr, size);
+ if (ret)
+ return ret;
+ target_offset = e->target_offset - (origsize - *size);
+
+ t = (struct ebt_entry_target *) ((char *) e + e->target_offset);
+
+ ret = compat_target_to_user(t, dstptr, size);
+ if (ret)
+ return ret;
+ next_offset = e->next_offset - (origsize - *size);
+
+ if (put_user(watchers_offset, &ce->watchers_offset) ||
+ put_user(target_offset, &ce->target_offset) ||
+ put_user(next_offset, &ce->next_offset))
+ return -EFAULT;
+
+ *size -= sizeof(*ce);
+ return 0;
+}
+
+static int compat_calc_match(struct ebt_entry_match *m, int *off)
+{
+ *off += ebt_compat_match_offset(m->u.match, m->match_size);
+ *off += ebt_compat_entry_padsize();
+ return 0;
+}
+
+static int compat_calc_watcher(struct ebt_entry_watcher *w, int *off)
+{
+ *off += xt_compat_target_offset(w->u.watcher);
+ *off += ebt_compat_entry_padsize();
+ return 0;
+}
+
+static int compat_calc_entry(const struct ebt_entry *e,
+ const struct ebt_table_info *info,
+ const void *base,
+ struct compat_ebt_replace *newinfo)
+{
+ const struct ebt_entry_target *t;
+ unsigned int entry_offset;
+ int off, ret, i;
+
+ if (e->bitmask == 0)
+ return 0;
+
+ off = 0;
+ entry_offset = (void *)e - base;
+
+ EBT_MATCH_ITERATE(e, compat_calc_match, &off);
+ EBT_WATCHER_ITERATE(e, compat_calc_watcher, &off);
+
+ t = (const struct ebt_entry_target *) ((char *) e + e->target_offset);
+
+ off += xt_compat_target_offset(t->u.target);
+ off += ebt_compat_entry_padsize();
+
+ newinfo->entries_size -= off;
+
+ ret = xt_compat_add_offset(NFPROTO_BRIDGE, entry_offset, off);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < NF_BR_NUMHOOKS; i++) {
+ const void *hookptr = info->hook_entry[i];
+ if (info->hook_entry[i] &&
+ (e < (struct ebt_entry *)(base - hookptr))) {
+ newinfo->hook_entry[i] -= off;
+ pr_debug("0x%08X -> 0x%08X\n",
+ newinfo->hook_entry[i] + off,
+ newinfo->hook_entry[i]);
+ }
+ }
+
+ return 0;
+}
+
+
+static int compat_table_info(const struct ebt_table_info *info,
+ struct compat_ebt_replace *newinfo)
+{
+ unsigned int size = info->entries_size;
+ const void *entries = info->entries;
+
+ newinfo->entries_size = size;
+
+ return EBT_ENTRY_ITERATE(entries, size, compat_calc_entry, info,
+ entries, newinfo);
+}
+
+static int compat_copy_everything_to_user(struct ebt_table *t,
+ void __user *user, int *len, int cmd)
+{
+ struct compat_ebt_replace repl, tmp;
+ struct ebt_counter *oldcounters;
+ struct ebt_table_info tinfo;
+ int ret;
+ void __user *pos;
+
+ memset(&tinfo, 0, sizeof(tinfo));
+
+ if (cmd == EBT_SO_GET_ENTRIES) {
+ tinfo.entries_size = t->private->entries_size;
+ tinfo.nentries = t->private->nentries;
+ tinfo.entries = t->private->entries;
+ oldcounters = t->private->counters;
+ } else {
+ tinfo.entries_size = t->table->entries_size;
+ tinfo.nentries = t->table->nentries;
+ tinfo.entries = t->table->entries;
+ oldcounters = t->table->counters;
+ }
+
+ if (copy_from_user(&tmp, user, sizeof(tmp)))
+ return -EFAULT;
+
+ if (tmp.nentries != tinfo.nentries ||
+ (tmp.num_counters && tmp.num_counters != tinfo.nentries))
+ return -EINVAL;
+
+ memcpy(&repl, &tmp, sizeof(repl));
+ if (cmd == EBT_SO_GET_ENTRIES)
+ ret = compat_table_info(t->private, &repl);
+ else
+ ret = compat_table_info(&tinfo, &repl);
+ if (ret)
+ return ret;
+
+ if (*len != sizeof(tmp) + repl.entries_size +
+ (tmp.num_counters? tinfo.nentries * sizeof(struct ebt_counter): 0)) {
+ pr_err("wrong size: *len %d, entries_size %u, replsz %d\n",
+ *len, tinfo.entries_size, repl.entries_size);
+ return -EINVAL;
+ }
+
+ /* userspace might not need the counters */
+ ret = copy_counters_to_user(t, oldcounters, compat_ptr(tmp.counters),
+ tmp.num_counters, tinfo.nentries);
+ if (ret)
+ return ret;
+
+ pos = compat_ptr(tmp.entries);
+ return EBT_ENTRY_ITERATE(tinfo.entries, tinfo.entries_size,
+ compat_copy_entry_to_user, &pos, &tmp.entries_size);
+}
+
+struct ebt_entries_buf_state {
+ char *buf_kern_start; /* kernel buffer to copy (translated) data to */
+ u32 buf_kern_len; /* total size of kernel buffer */
+ u32 buf_kern_offset; /* amount of data copied so far */
+ u32 buf_user_offset; /* read position in userspace buffer */
+};
+
+static int ebt_buf_count(struct ebt_entries_buf_state *state, unsigned int sz)
+{
+ state->buf_kern_offset += sz;
+ return state->buf_kern_offset >= sz ? 0 : -EINVAL;
+}
+
+static int ebt_buf_add(struct ebt_entries_buf_state *state,
+ void *data, unsigned int sz)
+{
+ if (state->buf_kern_start == NULL)
+ goto count_only;
+
+ BUG_ON(state->buf_kern_offset + sz > state->buf_kern_len);
+
+ memcpy(state->buf_kern_start + state->buf_kern_offset, data, sz);
+
+ count_only:
+ state->buf_user_offset += sz;
+ return ebt_buf_count(state, sz);
+}
+
+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 (b != NULL && sz > 0)
+ memset(b + state->buf_kern_offset, 0, sz);
+ /* do not adjust ->buf_user_offset here, we added kernel-side padding */
+ return ebt_buf_count(state, sz);
+}
+
+enum compat_mwt {
+ EBT_COMPAT_MATCH,
+ EBT_COMPAT_WATCHER,
+ EBT_COMPAT_TARGET,
+};
+
+static int compat_mtw_from_user(struct compat_ebt_entry_mwt *mwt,
+ enum compat_mwt compat_mwt,
+ struct ebt_entries_buf_state *state,
+ const unsigned char *base)
+{
+ char name[EBT_FUNCTION_MAXNAMELEN];
+ struct xt_match *match;
+ struct xt_target *wt;
+ void *dst = NULL;
+ int off, pad = 0, ret = 0;
+ unsigned int size_kern, entry_offset, match_size = mwt->match_size;
+
+ strlcpy(name, mwt->u.name, sizeof(name));
+
+ if (state->buf_kern_start)
+ dst = state->buf_kern_start + state->buf_kern_offset;
+
+ entry_offset = (unsigned char *) mwt - base;
+ switch (compat_mwt) {
+ case EBT_COMPAT_MATCH:
+ match = try_then_request_module(xt_find_match(NFPROTO_BRIDGE,
+ name, 0), "ebt_%s", name);
+ if (match == NULL)
+ return -ENOENT;
+ if (IS_ERR(match))
+ return PTR_ERR(match);
+
+ off = ebt_compat_match_offset(match, match_size);
+ if (dst) {
+ if (match->compat_from_user)
+ match->compat_from_user(dst, mwt->data);
+ else
+ memcpy(dst, mwt->data, match_size);
+ }
+
+ size_kern = match->matchsize;
+ if (unlikely(size_kern == -1))
+ size_kern = match_size;
+ module_put(match->me);
+ break;
+ case EBT_COMPAT_WATCHER: /* fallthrough */
+ case EBT_COMPAT_TARGET:
+ wt = try_then_request_module(xt_find_target(NFPROTO_BRIDGE,
+ name, 0), "ebt_%s", name);
+ if (wt == NULL)
+ return -ENOENT;
+ if (IS_ERR(wt))
+ return PTR_ERR(wt);
+ off = xt_compat_target_offset(wt);
+
+ if (dst) {
+ if (wt->compat_from_user)
+ wt->compat_from_user(dst, mwt->data);
+ else
+ memcpy(dst, mwt->data, match_size);
+ }
+
+ size_kern = wt->targetsize;
+ module_put(wt->me);
+ break;
+ }
+
+ if (!dst) {
+ ret = xt_compat_add_offset(NFPROTO_BRIDGE, entry_offset,
+ off + ebt_compat_entry_padsize());
+ if (ret < 0)
+ return ret;
+ }
+
+ state->buf_kern_offset += match_size + off;
+ state->buf_user_offset += match_size;
+ 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);
+ memset(dst + size_kern, 0, pad);
+ }
+ return off + match_size;
+}
+
+/*
+ * return size of all matches, watchers or target, including necessary
+ * alignment and padding.
+ */
+static int ebt_size_mwt(struct compat_ebt_entry_mwt *match32,
+ unsigned int size_left, enum compat_mwt type,
+ struct ebt_entries_buf_state *state, const void *base)
+{
+ int growth = 0;
+ char *buf;
+
+ if (size_left == 0)
+ return 0;
+
+ buf = (char *) match32;
+
+ while (size_left >= sizeof(*match32)) {
+ struct ebt_entry_match *match_kern;
+ int ret;
+
+ match_kern = (struct ebt_entry_match *) state->buf_kern_start;
+ if (match_kern) {
+ char *tmp;
+ tmp = state->buf_kern_start + state->buf_kern_offset;
+ match_kern = (struct ebt_entry_match *) tmp;
+ }
+ ret = ebt_buf_add(state, buf, sizeof(*match32));
+ if (ret < 0)
+ return ret;
+ size_left -= sizeof(*match32);
+
+ /* add padding before match->data (if any) */
+ ret = ebt_buf_add_pad(state, ebt_compat_entry_padsize());
+ if (ret < 0)
+ return ret;
+
+ if (match32->match_size > size_left)
+ return -EINVAL;
+
+ size_left -= match32->match_size;
+
+ ret = compat_mtw_from_user(match32, type, state, base);
+ if (ret < 0)
+ return ret;
+
+ BUG_ON(ret < match32->match_size);
+ growth += ret - match32->match_size;
+ growth += ebt_compat_entry_padsize();
+
+ buf += sizeof(*match32);
+ buf += match32->match_size;
+
+ if (match_kern)
+ match_kern->match_size = ret;
+
+ WARN_ON(type == EBT_COMPAT_TARGET && size_left);
+ match32 = (struct compat_ebt_entry_mwt *) buf;
+ }
+
+ return growth;
+}
+
+#define EBT_COMPAT_WATCHER_ITERATE(e, fn, args...) \
+({ \
+ unsigned int __i; \
+ int __ret = 0; \
+ struct compat_ebt_entry_mwt *__watcher; \
+ \
+ for (__i = e->watchers_offset; \
+ __i < (e)->target_offset; \
+ __i += __watcher->watcher_size + \
+ sizeof(struct compat_ebt_entry_mwt)) { \
+ __watcher = (void *)(e) + __i; \
+ __ret = fn(__watcher , ## args); \
+ if (__ret != 0) \
+ break; \
+ } \
+ if (__ret == 0) { \
+ if (__i != (e)->target_offset) \
+ __ret = -EINVAL; \
+ } \
+ __ret; \
+})
+
+#define EBT_COMPAT_MATCH_ITERATE(e, fn, args...) \
+({ \
+ unsigned int __i; \
+ int __ret = 0; \
+ struct compat_ebt_entry_mwt *__match; \
+ \
+ for (__i = sizeof(struct ebt_entry); \
+ __i < (e)->watchers_offset; \
+ __i += __match->match_size + \
+ sizeof(struct compat_ebt_entry_mwt)) { \
+ __match = (void *)(e) + __i; \
+ __ret = fn(__match , ## args); \
+ if (__ret != 0) \
+ break; \
+ } \
+ if (__ret == 0) { \
+ if (__i != (e)->watchers_offset) \
+ __ret = -EINVAL; \
+ } \
+ __ret; \
+})
+
+/* called for all ebt_entry structures. */
+static int size_entry_mwt(struct ebt_entry *entry, const unsigned char *base,
+ unsigned int *total,
+ struct ebt_entries_buf_state *state)
+{
+ unsigned int i, j, startoff, new_offset = 0;
+ /* stores match/watchers/targets & offset of next struct ebt_entry: */
+ unsigned int offsets[4];
+ unsigned int *offsets_update = NULL;
+ int ret;
+ char *buf_start;
+
+ if (*total < sizeof(struct ebt_entries))
+ return -EINVAL;
+
+ if (!entry->bitmask) {
+ *total -= sizeof(struct ebt_entries);
+ return ebt_buf_add(state, entry, sizeof(struct ebt_entries));
+ }
+ if (*total < sizeof(*entry) || entry->next_offset < sizeof(*entry))
+ return -EINVAL;
+
+ startoff = state->buf_user_offset;
+ /* pull in most part of ebt_entry, it does not need to be changed. */
+ ret = ebt_buf_add(state, entry,
+ offsetof(struct ebt_entry, watchers_offset));
+ if (ret < 0)
+ return ret;
+
+ offsets[0] = sizeof(struct ebt_entry); /* matches come first */
+ memcpy(&offsets[1], &entry->watchers_offset,
+ sizeof(offsets) - sizeof(offsets[0]));
+
+ if (state->buf_kern_start) {
+ buf_start = state->buf_kern_start + state->buf_kern_offset;
+ offsets_update = (unsigned int *) buf_start;
+ }
+ ret = ebt_buf_add(state, &offsets[1],
+ sizeof(offsets) - sizeof(offsets[0]));
+ if (ret < 0)
+ return ret;
+ buf_start = (char *) entry;
+ /*
+ * 0: matches offset, always follows ebt_entry.
+ * 1: watchers offset, from ebt_entry structure
+ * 2: target offset, from ebt_entry structure
+ * 3: next ebt_entry offset, from ebt_entry structure
+ *
+ * offsets are relative to beginning of struct ebt_entry (i.e., 0).
+ */
+ for (i = 0, j = 1 ; j < 4 ; j++, i++) {
+ struct compat_ebt_entry_mwt *match32;
+ unsigned int size;
+ char *buf = buf_start;
+
+ buf = buf_start + offsets[i];
+ if (offsets[i] > offsets[j])
+ return -EINVAL;
+
+ match32 = (struct compat_ebt_entry_mwt *) buf;
+ size = offsets[j] - offsets[i];
+ ret = ebt_size_mwt(match32, size, i, state, base);
+ if (ret < 0)
+ return ret;
+ new_offset += ret;
+ if (offsets_update && new_offset) {
+ pr_debug("ebtables: change offset %d to %d\n",
+ offsets_update[i], offsets[j] + new_offset);
+ offsets_update[i] = offsets[j] + new_offset;
+ }
+ }
+
+ startoff = state->buf_user_offset - startoff;
+
+ BUG_ON(*total < startoff);
+ *total -= startoff;
+ return 0;
+}
+
+/*
+ * repl->entries_size is the size of the ebt_entry blob in userspace.
+ * It might need more memory when copied to a 64 bit kernel in case
+ * userspace is 32-bit. So, first task: find out how much memory is needed.
+ *
+ * Called before validation is performed.
+ */
+static int compat_copy_entries(unsigned char *data, unsigned int size_user,
+ struct ebt_entries_buf_state *state)
+{
+ unsigned int size_remaining = size_user;
+ int ret;
+
+ ret = EBT_ENTRY_ITERATE(data, size_user, size_entry_mwt, data,
+ &size_remaining, state);
+ if (ret < 0)
+ return ret;
+
+ WARN_ON(size_remaining);
+ return state->buf_kern_offset;
+}
+
+
+static int compat_copy_ebt_replace_from_user(struct ebt_replace *repl,
+ void __user *user, unsigned int len)
+{
+ struct compat_ebt_replace tmp;
+ int i;
+
+ if (len < sizeof(tmp))
+ return -EINVAL;
+
+ if (copy_from_user(&tmp, user, sizeof(tmp)))
+ return -EFAULT;
+
+ if (len != sizeof(tmp) + tmp.entries_size)
+ return -EINVAL;
+
+ if (tmp.entries_size == 0)
+ return -EINVAL;
+
+ if (tmp.nentries >= ((INT_MAX - sizeof(struct ebt_table_info)) /
+ NR_CPUS - SMP_CACHE_BYTES) / sizeof(struct ebt_counter))
+ return -ENOMEM;
+ if (tmp.num_counters >= INT_MAX / sizeof(struct ebt_counter))
+ return -ENOMEM;
+
+ memcpy(repl, &tmp, offsetof(struct ebt_replace, hook_entry));
+
+ /* starting with hook_entry, 32 vs. 64 bit structures are different */
+ for (i = 0; i < NF_BR_NUMHOOKS; i++)
+ repl->hook_entry[i] = compat_ptr(tmp.hook_entry[i]);
+
+ repl->num_counters = tmp.num_counters;
+ repl->counters = compat_ptr(tmp.counters);
+ repl->entries = compat_ptr(tmp.entries);
+ return 0;
+}
+
+static int compat_do_replace(struct net *net, void __user *user,
+ unsigned int len)
+{
+ int ret, i, countersize, size64;
+ struct ebt_table_info *newinfo;
+ struct ebt_replace tmp;
+ struct ebt_entries_buf_state state;
+ void *entries_tmp;
+
+ ret = compat_copy_ebt_replace_from_user(&tmp, user, len);
+ if (ret)
+ return ret;
+
+ countersize = COUNTER_OFFSET(tmp.nentries) * nr_cpu_ids;
+ newinfo = vmalloc(sizeof(*newinfo) + countersize);
+ if (!newinfo)
+ return -ENOMEM;
+
+ if (countersize)
+ memset(newinfo->counters, 0, countersize);
+
+ memset(&state, 0, sizeof(state));
+
+ newinfo->entries = vmalloc(tmp.entries_size);
+ if (!newinfo->entries) {
+ ret = -ENOMEM;
+ goto free_newinfo;
+ }
+ if (copy_from_user(
+ newinfo->entries, tmp.entries, tmp.entries_size) != 0) {
+ ret = -EFAULT;
+ goto free_entries;
+ }
+
+ entries_tmp = newinfo->entries;
+
+ xt_compat_lock(NFPROTO_BRIDGE);
+
+ ret = compat_copy_entries(entries_tmp, tmp.entries_size, &state);
+ if (ret < 0)
+ goto out_unlock;
+
+ pr_debug("tmp.entries_size %d, kern off %d, user off %d delta %d\n",
+ tmp.entries_size, state.buf_kern_offset, state.buf_user_offset,
+ xt_compat_calc_jump(NFPROTO_BRIDGE, tmp.entries_size));
+
+ size64 = ret;
+ newinfo->entries = vmalloc(size64);
+ if (!newinfo->entries) {
+ vfree(entries_tmp);
+ ret = -ENOMEM;
+ goto out_unlock;
+ }
+
+ memset(&state, 0, sizeof(state));
+ state.buf_kern_start = newinfo->entries;
+ state.buf_kern_len = size64;
+
+ ret = compat_copy_entries(entries_tmp, tmp.entries_size, &state);
+ BUG_ON(ret < 0); /* parses same data again */
+
+ vfree(entries_tmp);
+ tmp.entries_size = size64;
+
+ for (i = 0; i < NF_BR_NUMHOOKS; i++) {
+ char __user *usrptr;
+ if (tmp.hook_entry[i]) {
+ unsigned int delta;
+ usrptr = (char __user *) tmp.hook_entry[i];
+ delta = usrptr - tmp.entries;
+ usrptr += xt_compat_calc_jump(NFPROTO_BRIDGE, delta);
+ tmp.hook_entry[i] = (struct ebt_entries __user *)usrptr;
+ }
+ }
+
+ xt_compat_flush_offsets(NFPROTO_BRIDGE);
+ xt_compat_unlock(NFPROTO_BRIDGE);
+
+ ret = do_replace_finish(net, &tmp, newinfo);
+ if (ret == 0)
+ return ret;
+free_entries:
+ vfree(newinfo->entries);
+free_newinfo:
+ vfree(newinfo);
+ return ret;
+out_unlock:
+ xt_compat_flush_offsets(NFPROTO_BRIDGE);
+ xt_compat_unlock(NFPROTO_BRIDGE);
+ goto free_entries;
+}
+
+static int compat_update_counters(struct net *net, void __user *user,
+ unsigned int len)
+{
+ struct compat_ebt_replace hlp;
+
+ if (copy_from_user(&hlp, user, sizeof(hlp)))
+ return -EFAULT;
+
+ if (len != sizeof(hlp) + hlp.num_counters * sizeof(struct ebt_counter))
+ return -EINVAL;
+
+ return do_update_counters(net, hlp.name, compat_ptr(hlp.counters),
+ hlp.num_counters, user, len);
+}
+
+static int compat_do_ebt_set_ctl(struct sock *sk,
+ int cmd, void __user *user, unsigned int len)
+{
+ int ret;
+
+ if (!capable(CAP_NET_ADMIN))
+ return -EPERM;
+
+ switch (cmd) {
+ case EBT_SO_SET_ENTRIES:
+ ret = compat_do_replace(sock_net(sk), user, len);
+ break;
+ case EBT_SO_SET_COUNTERS:
+ ret = compat_update_counters(sock_net(sk), user, len);
+ break;
+ default:
+ ret = -EINVAL;
+ }
+ return ret;
+}
+
+static int compat_do_ebt_get_ctl(struct sock *sk, int cmd,
+ void __user *user, int *len)
+{
+ int ret;
+ struct compat_ebt_replace tmp;
+ struct ebt_table *t;
+
+ if (!capable(CAP_NET_ADMIN))
+ return -EPERM;
+
+ if ((cmd == EBT_SO_GET_INFO ||
+ cmd == EBT_SO_GET_INIT_INFO) && *len != sizeof(tmp))
+ return -EINVAL;
+
+ if (copy_from_user(&tmp, user, sizeof(tmp)))
+ return -EFAULT;
+
+ t = find_table_lock(sock_net(sk), tmp.name, &ret, &ebt_mutex);
+ if (!t)
+ return ret;
+
+ xt_compat_lock(NFPROTO_BRIDGE);
+ switch (cmd) {
+ case EBT_SO_GET_INFO:
+ tmp.nentries = t->private->nentries;
+ ret = compat_table_info(t->private, &tmp);
+ if (ret)
+ goto out;
+ tmp.valid_hooks = t->valid_hooks;
+
+ if (copy_to_user(user, &tmp, *len) != 0) {
+ ret = -EFAULT;
+ break;
+ }
+ ret = 0;
+ break;
+ case EBT_SO_GET_INIT_INFO:
+ tmp.nentries = t->table->nentries;
+ tmp.entries_size = t->table->entries_size;
+ tmp.valid_hooks = t->table->valid_hooks;
+
+ if (copy_to_user(user, &tmp, *len) != 0) {
+ ret = -EFAULT;
+ break;
+ }
+ ret = 0;
+ break;
+ case EBT_SO_GET_ENTRIES:
+ case EBT_SO_GET_INIT_ENTRIES:
+ ret = compat_copy_everything_to_user(t, user, len, cmd);
+ break;
+ default:
+ ret = -EINVAL;
+ }
+ out:
+ xt_compat_flush_offsets(NFPROTO_BRIDGE);
+ xt_compat_unlock(NFPROTO_BRIDGE);
+ mutex_unlock(&ebt_mutex);
+ return ret;
+}
+#endif
+
static struct nf_sockopt_ops ebt_sockopts =
{
.pf = PF_INET,
.set_optmin = EBT_BASE_CTL,
.set_optmax = EBT_SO_SET_MAX + 1,
.set = do_ebt_set_ctl,
+#ifdef CONFIG_COMPAT
+ .compat_set = compat_do_ebt_set_ctl,
+#endif
.get_optmin = EBT_BASE_CTL,
.get_optmax = EBT_SO_GET_MAX + 1,
.get = do_ebt_get_ctl,
+#ifdef CONFIG_COMPAT
+ .compat_get = compat_do_ebt_get_ctl,
+#endif
.owner = THIS_MODULE,
};
--
1.6.3.3
--
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