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Diffstat (limited to 'net/core/filter.c')
-rw-r--r--net/core/filter.c54
1 files changed, 12 insertions, 42 deletions
diff --git a/net/core/filter.c b/net/core/filter.c
index d814b8a89d0f..647b12265e18 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -51,9 +51,9 @@
* @skb: buffer to filter
*
* Run the filter code and then cut skb->data to correct size returned by
- * sk_run_filter. If pkt_len is 0 we toss packet. If skb->len is smaller
+ * SK_RUN_FILTER. If pkt_len is 0 we toss packet. If skb->len is smaller
* than pkt_len we keep whole skb->data. This is the socket level
- * wrapper to sk_run_filter. It returns 0 if the packet should
+ * wrapper to SK_RUN_FILTER. It returns 0 if the packet should
* be accepted or -EPERM if the packet should be tossed.
*
*/
@@ -87,33 +87,9 @@ int sk_filter(struct sock *sk, struct sk_buff *skb)
}
EXPORT_SYMBOL(sk_filter);
-/* Helper to find the offset of pkt_type in sk_buff structure. We want
- * to make sure its still a 3bit field starting at a byte boundary;
- * taken from arch/x86/net/bpf_jit_comp.c.
- */
-#ifdef __BIG_ENDIAN_BITFIELD
-#define PKT_TYPE_MAX (7 << 5)
-#else
-#define PKT_TYPE_MAX 7
-#endif
-static unsigned int pkt_type_offset(void)
-{
- struct sk_buff skb_probe = { .pkt_type = ~0, };
- u8 *ct = (u8 *) &skb_probe;
- unsigned int off;
-
- for (off = 0; off < sizeof(struct sk_buff); off++) {
- if (ct[off] == PKT_TYPE_MAX)
- return off;
- }
-
- pr_err_once("Please fix %s, as pkt_type couldn't be found!\n", __func__);
- return -1;
-}
-
static u64 __skb_get_pay_offset(u64 ctx, u64 a, u64 x, u64 r4, u64 r5)
{
- return __skb_get_poff((struct sk_buff *)(unsigned long) ctx);
+ return skb_get_poff((struct sk_buff *)(unsigned long) ctx);
}
static u64 __skb_get_nlattr(u64 ctx, u64 a, u64 x, u64 r4, u64 r5)
@@ -190,11 +166,8 @@ static bool convert_bpf_extensions(struct sock_filter *fp,
break;
case SKF_AD_OFF + SKF_AD_PKTTYPE:
- *insn = BPF_LDX_MEM(BPF_B, BPF_REG_A, BPF_REG_CTX,
- pkt_type_offset());
- if (insn->off < 0)
- return false;
- insn++;
+ *insn++ = BPF_LDX_MEM(BPF_B, BPF_REG_A, BPF_REG_CTX,
+ PKT_TYPE_OFFSET());
*insn = BPF_ALU32_IMM(BPF_AND, BPF_REG_A, PKT_TYPE_MAX);
#ifdef __BIG_ENDIAN_BITFIELD
insn++;
@@ -593,11 +566,8 @@ err:
/* Security:
*
- * A BPF program is able to use 16 cells of memory to store intermediate
- * values (check u32 mem[BPF_MEMWORDS] in sk_run_filter()).
- *
* As we dont want to clear mem[] array for each packet going through
- * sk_run_filter(), we check that filter loaded by user never try to read
+ * __bpf_prog_run(), we check that filter loaded by user never try to read
* a cell if not previously written, and we check all branches to be sure
* a malicious user doesn't try to abuse us.
*/
@@ -933,7 +903,7 @@ static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp)
/* Expand fp for appending the new filter representation. */
old_fp = fp;
- fp = krealloc(old_fp, bpf_prog_size(new_len), GFP_KERNEL);
+ fp = bpf_prog_realloc(old_fp, bpf_prog_size(new_len), 0);
if (!fp) {
/* The old_fp is still around in case we couldn't
* allocate new memory, so uncharge on that one.
@@ -972,7 +942,7 @@ static struct bpf_prog *bpf_prepare_filter(struct bpf_prog *fp)
int err;
fp->bpf_func = NULL;
- fp->jited = 0;
+ fp->jited = false;
err = bpf_check_classic(fp->insns, fp->len);
if (err) {
@@ -1013,7 +983,7 @@ int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog)
if (fprog->filter == NULL)
return -EINVAL;
- fp = kmalloc(bpf_prog_size(fprog->len), GFP_KERNEL);
+ fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
if (!fp)
return -ENOMEM;
@@ -1069,12 +1039,12 @@ int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
if (fprog->filter == NULL)
return -EINVAL;
- prog = kmalloc(bpf_fsize, GFP_KERNEL);
+ prog = bpf_prog_alloc(bpf_fsize, 0);
if (!prog)
return -ENOMEM;
if (copy_from_user(prog->insns, fprog->filter, fsize)) {
- kfree(prog);
+ __bpf_prog_free(prog);
return -EFAULT;
}
@@ -1082,7 +1052,7 @@ int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
err = bpf_prog_store_orig_filter(prog, fprog);
if (err) {
- kfree(prog);
+ __bpf_prog_free(prog);
return -ENOMEM;
}