netfilter: ebtables: add CONFIG_COMPAT support
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@astaro.com>
This commit is contained in:
Florian Westphal
Florian Westphal
Родитель
49facff9f9
Коммит
81e675c227
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@ -51,11 +51,37 @@
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static DEFINE_MUTEX(ebt_mutex);
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#ifdef CONFIG_COMPAT
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static void ebt_standard_compat_from_user(void *dst, const void *src)
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{
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int v = *(compat_int_t *)src;
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if (v >= 0)
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v += xt_compat_calc_jump(NFPROTO_BRIDGE, v);
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memcpy(dst, &v, sizeof(v));
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}
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static int ebt_standard_compat_to_user(void __user *dst, const void *src)
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{
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compat_int_t cv = *(int *)src;
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if (cv >= 0)
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cv -= xt_compat_calc_jump(NFPROTO_BRIDGE, cv);
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return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0;
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}
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#endif
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static struct xt_target ebt_standard_target = {
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.name = "standard",
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.revision = 0,
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.family = NFPROTO_BRIDGE,
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.targetsize = sizeof(int),
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#ifdef CONFIG_COMPAT
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.compatsize = sizeof(compat_int_t),
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.compat_from_user = ebt_standard_compat_from_user,
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.compat_to_user = ebt_standard_compat_to_user,
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#endif
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};
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static inline int
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@ -1454,7 +1480,7 @@ static int do_ebt_set_ctl(struct sock *sk,
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break;
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default:
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ret = -EINVAL;
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}
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}
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return ret;
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}
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@ -1514,15 +1540,874 @@ static int do_ebt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
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return ret;
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}
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#ifdef CONFIG_COMPAT
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/* 32 bit-userspace compatibility definitions. */
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struct compat_ebt_replace {
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char name[EBT_TABLE_MAXNAMELEN];
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compat_uint_t valid_hooks;
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compat_uint_t nentries;
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compat_uint_t entries_size;
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/* start of the chains */
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compat_uptr_t hook_entry[NF_BR_NUMHOOKS];
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/* nr of counters userspace expects back */
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compat_uint_t num_counters;
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/* where the kernel will put the old counters. */
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compat_uptr_t counters;
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compat_uptr_t entries;
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};
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/* struct ebt_entry_match, _target and _watcher have same layout */
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struct compat_ebt_entry_mwt {
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union {
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char name[EBT_FUNCTION_MAXNAMELEN];
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compat_uptr_t ptr;
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} u;
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compat_uint_t match_size;
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compat_uint_t data[0];
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};
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/* account for possible padding between match_size and ->data */
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static int ebt_compat_entry_padsize(void)
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{
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BUILD_BUG_ON(XT_ALIGN(sizeof(struct ebt_entry_match)) <
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COMPAT_XT_ALIGN(sizeof(struct compat_ebt_entry_mwt)));
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return (int) XT_ALIGN(sizeof(struct ebt_entry_match)) -
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COMPAT_XT_ALIGN(sizeof(struct compat_ebt_entry_mwt));
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}
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static int ebt_compat_match_offset(const struct xt_match *match,
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unsigned int userlen)
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{
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/*
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* ebt_among needs special handling. The kernel .matchsize is
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* set to -1 at registration time; at runtime an EBT_ALIGN()ed
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* value is expected.
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* Example: userspace sends 4500, ebt_among.c wants 4504.
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*/
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if (unlikely(match->matchsize == -1))
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return XT_ALIGN(userlen) - COMPAT_XT_ALIGN(userlen);
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return xt_compat_match_offset(match);
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}
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static int compat_match_to_user(struct ebt_entry_match *m, void __user **dstptr,
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unsigned int *size)
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{
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const struct xt_match *match = m->u.match;
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struct compat_ebt_entry_mwt __user *cm = *dstptr;
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int off = ebt_compat_match_offset(match, m->match_size);
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compat_uint_t msize = m->match_size - off;
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BUG_ON(off >= m->match_size);
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if (copy_to_user(cm->u.name, match->name,
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strlen(match->name) + 1) || put_user(msize, &cm->match_size))
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return -EFAULT;
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if (match->compat_to_user) {
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if (match->compat_to_user(cm->data, m->data))
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return -EFAULT;
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} else if (copy_to_user(cm->data, m->data, msize))
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return -EFAULT;
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*size -= ebt_compat_entry_padsize() + off;
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*dstptr = cm->data;
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*dstptr += msize;
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return 0;
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}
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static int compat_target_to_user(struct ebt_entry_target *t,
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void __user **dstptr,
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unsigned int *size)
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{
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const struct xt_target *target = t->u.target;
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struct compat_ebt_entry_mwt __user *cm = *dstptr;
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int off = xt_compat_target_offset(target);
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compat_uint_t tsize = t->target_size - off;
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BUG_ON(off >= t->target_size);
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if (copy_to_user(cm->u.name, target->name,
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strlen(target->name) + 1) || put_user(tsize, &cm->match_size))
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return -EFAULT;
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if (target->compat_to_user) {
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if (target->compat_to_user(cm->data, t->data))
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return -EFAULT;
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} else if (copy_to_user(cm->data, t->data, tsize))
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return -EFAULT;
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*size -= ebt_compat_entry_padsize() + off;
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*dstptr = cm->data;
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*dstptr += tsize;
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return 0;
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}
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static int compat_watcher_to_user(struct ebt_entry_watcher *w,
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void __user **dstptr,
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unsigned int *size)
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{
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return compat_target_to_user((struct ebt_entry_target *)w,
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dstptr, size);
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}
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static int compat_copy_entry_to_user(struct ebt_entry *e, void __user **dstptr,
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unsigned int *size)
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{
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struct ebt_entry_target *t;
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struct ebt_entry __user *ce;
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u32 watchers_offset, target_offset, next_offset;
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compat_uint_t origsize;
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int ret;
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if (e->bitmask == 0) {
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if (*size < sizeof(struct ebt_entries))
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return -EINVAL;
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if (copy_to_user(*dstptr, e, sizeof(struct ebt_entries)))
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return -EFAULT;
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*dstptr += sizeof(struct ebt_entries);
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*size -= sizeof(struct ebt_entries);
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return 0;
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}
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if (*size < sizeof(*ce))
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return -EINVAL;
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ce = (struct ebt_entry __user *)*dstptr;
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if (copy_to_user(ce, e, sizeof(*ce)))
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return -EFAULT;
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origsize = *size;
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*dstptr += sizeof(*ce);
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ret = EBT_MATCH_ITERATE(e, compat_match_to_user, dstptr, size);
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if (ret)
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return ret;
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watchers_offset = e->watchers_offset - (origsize - *size);
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ret = EBT_WATCHER_ITERATE(e, compat_watcher_to_user, dstptr, size);
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if (ret)
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return ret;
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target_offset = e->target_offset - (origsize - *size);
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t = (struct ebt_entry_target *) ((char *) e + e->target_offset);
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ret = compat_target_to_user(t, dstptr, size);
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if (ret)
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return ret;
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next_offset = e->next_offset - (origsize - *size);
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if (put_user(watchers_offset, &ce->watchers_offset) ||
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put_user(target_offset, &ce->target_offset) ||
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put_user(next_offset, &ce->next_offset))
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return -EFAULT;
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*size -= sizeof(*ce);
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return 0;
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}
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static int compat_calc_match(struct ebt_entry_match *m, int *off)
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{
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*off += ebt_compat_match_offset(m->u.match, m->match_size);
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*off += ebt_compat_entry_padsize();
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return 0;
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}
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static int compat_calc_watcher(struct ebt_entry_watcher *w, int *off)
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{
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*off += xt_compat_target_offset(w->u.watcher);
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*off += ebt_compat_entry_padsize();
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return 0;
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}
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static int compat_calc_entry(const struct ebt_entry *e,
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const struct ebt_table_info *info,
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const void *base,
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struct compat_ebt_replace *newinfo)
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{
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const struct ebt_entry_target *t;
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unsigned int entry_offset;
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int off, ret, i;
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if (e->bitmask == 0)
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return 0;
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off = 0;
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entry_offset = (void *)e - base;
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EBT_MATCH_ITERATE(e, compat_calc_match, &off);
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EBT_WATCHER_ITERATE(e, compat_calc_watcher, &off);
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t = (const struct ebt_entry_target *) ((char *) e + e->target_offset);
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off += xt_compat_target_offset(t->u.target);
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off += ebt_compat_entry_padsize();
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newinfo->entries_size -= off;
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ret = xt_compat_add_offset(NFPROTO_BRIDGE, entry_offset, off);
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if (ret)
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return ret;
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for (i = 0; i < NF_BR_NUMHOOKS; i++) {
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const void *hookptr = info->hook_entry[i];
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if (info->hook_entry[i] &&
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(e < (struct ebt_entry *)(base - hookptr))) {
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newinfo->hook_entry[i] -= off;
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pr_debug("0x%08X -> 0x%08X\n",
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newinfo->hook_entry[i] + off,
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newinfo->hook_entry[i]);
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}
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}
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return 0;
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}
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static int compat_table_info(const struct ebt_table_info *info,
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struct compat_ebt_replace *newinfo)
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{
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unsigned int size = info->entries_size;
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const void *entries = info->entries;
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newinfo->entries_size = size;
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return EBT_ENTRY_ITERATE(entries, size, compat_calc_entry, info,
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entries, newinfo);
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}
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static int compat_copy_everything_to_user(struct ebt_table *t,
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void __user *user, int *len, int cmd)
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{
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struct compat_ebt_replace repl, tmp;
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struct ebt_counter *oldcounters;
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struct ebt_table_info tinfo;
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int ret;
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void __user *pos;
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memset(&tinfo, 0, sizeof(tinfo));
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if (cmd == EBT_SO_GET_ENTRIES) {
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tinfo.entries_size = t->private->entries_size;
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tinfo.nentries = t->private->nentries;
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tinfo.entries = t->private->entries;
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oldcounters = t->private->counters;
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} else {
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tinfo.entries_size = t->table->entries_size;
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tinfo.nentries = t->table->nentries;
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tinfo.entries = t->table->entries;
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oldcounters = t->table->counters;
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}
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if (copy_from_user(&tmp, user, sizeof(tmp)))
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return -EFAULT;
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if (tmp.nentries != tinfo.nentries ||
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(tmp.num_counters && tmp.num_counters != tinfo.nentries))
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return -EINVAL;
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memcpy(&repl, &tmp, sizeof(repl));
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if (cmd == EBT_SO_GET_ENTRIES)
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ret = compat_table_info(t->private, &repl);
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else
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ret = compat_table_info(&tinfo, &repl);
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if (ret)
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return ret;
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if (*len != sizeof(tmp) + repl.entries_size +
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(tmp.num_counters? tinfo.nentries * sizeof(struct ebt_counter): 0)) {
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pr_err("wrong size: *len %d, entries_size %u, replsz %d\n",
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*len, tinfo.entries_size, repl.entries_size);
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return -EINVAL;
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}
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/* userspace might not need the counters */
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ret = copy_counters_to_user(t, oldcounters, compat_ptr(tmp.counters),
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tmp.num_counters, tinfo.nentries);
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if (ret)
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return ret;
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pos = compat_ptr(tmp.entries);
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return EBT_ENTRY_ITERATE(tinfo.entries, tinfo.entries_size,
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compat_copy_entry_to_user, &pos, &tmp.entries_size);
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}
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struct ebt_entries_buf_state {
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char *buf_kern_start; /* kernel buffer to copy (translated) data to */
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u32 buf_kern_len; /* total size of kernel buffer */
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u32 buf_kern_offset; /* amount of data copied so far */
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u32 buf_user_offset; /* read position in userspace buffer */
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};
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static int ebt_buf_count(struct ebt_entries_buf_state *state, unsigned int sz)
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{
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state->buf_kern_offset += sz;
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return state->buf_kern_offset >= sz ? 0 : -EINVAL;
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}
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static int ebt_buf_add(struct ebt_entries_buf_state *state,
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void *data, unsigned int sz)
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{
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if (state->buf_kern_start == NULL)
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goto count_only;
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BUG_ON(state->buf_kern_offset + sz > state->buf_kern_len);
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memcpy(state->buf_kern_start + state->buf_kern_offset, data, sz);
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count_only:
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state->buf_user_offset += sz;
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return ebt_buf_count(state, sz);
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}
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static int ebt_buf_add_pad(struct ebt_entries_buf_state *state, unsigned int sz)
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{
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char *b = state->buf_kern_start;
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BUG_ON(b && state->buf_kern_offset > state->buf_kern_len);
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if (b != NULL && sz > 0)
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memset(b + state->buf_kern_offset, 0, sz);
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/* do not adjust ->buf_user_offset here, we added kernel-side padding */
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return ebt_buf_count(state, sz);
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}
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enum compat_mwt {
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EBT_COMPAT_MATCH,
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EBT_COMPAT_WATCHER,
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EBT_COMPAT_TARGET,
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};
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static int compat_mtw_from_user(struct compat_ebt_entry_mwt *mwt,
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enum compat_mwt compat_mwt,
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struct ebt_entries_buf_state *state,
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const unsigned char *base)
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{
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char name[EBT_FUNCTION_MAXNAMELEN];
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struct xt_match *match;
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struct xt_target *wt;
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void *dst = NULL;
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int off, pad = 0, ret = 0;
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unsigned int size_kern, entry_offset, match_size = mwt->match_size;
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strlcpy(name, mwt->u.name, sizeof(name));
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if (state->buf_kern_start)
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dst = state->buf_kern_start + state->buf_kern_offset;
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entry_offset = (unsigned char *) mwt - base;
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switch (compat_mwt) {
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case EBT_COMPAT_MATCH:
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match = try_then_request_module(xt_find_match(NFPROTO_BRIDGE,
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name, 0), "ebt_%s", name);
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if (match == NULL)
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return -ENOENT;
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if (IS_ERR(match))
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return PTR_ERR(match);
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off = ebt_compat_match_offset(match, match_size);
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if (dst) {
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if (match->compat_from_user)
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match->compat_from_user(dst, mwt->data);
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else
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memcpy(dst, mwt->data, match_size);
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}
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size_kern = match->matchsize;
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if (unlikely(size_kern == -1))
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size_kern = match_size;
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module_put(match->me);
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break;
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case EBT_COMPAT_WATCHER: /* fallthrough */
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case EBT_COMPAT_TARGET:
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wt = try_then_request_module(xt_find_target(NFPROTO_BRIDGE,
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name, 0), "ebt_%s", name);
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if (wt == NULL)
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return -ENOENT;
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if (IS_ERR(wt))
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return PTR_ERR(wt);
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off = xt_compat_target_offset(wt);
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if (dst) {
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if (wt->compat_from_user)
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wt->compat_from_user(dst, mwt->data);
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else
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memcpy(dst, mwt->data, match_size);
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}
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size_kern = wt->targetsize;
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module_put(wt->me);
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break;
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}
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if (!dst) {
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ret = xt_compat_add_offset(NFPROTO_BRIDGE, entry_offset,
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off + ebt_compat_entry_padsize());
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if (ret < 0)
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return ret;
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}
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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,
|
||||
};
|
||||
|
||||
|
|
|
|||
Загрузка…
Ссылка в новой задаче