diff options
| author | Florian Westphal <fw@strlen.de> | 2023-12-12 19:13:14 +0100 |
|---|---|---|
| committer | Florian Westphal <fw@strlen.de> | 2023-12-15 02:27:14 +0100 |
| commit | ef10d65db278d77208e960d210a1f4f532ebb552 (patch) | |
| tree | 354f10077f748e440f15b205071610c7c1f273b3 /src/parser_bison.y | |
| parent | 8eeedce89d8bf0ad58da398782c2ca8a91d83a32 (diff) | |
src: reject large raw payload and concat expressions
The kernel will reject this too, but unfortunately nft may try
to cram the data into the underlying libnftnl expr.
This causes heap corruption or
BUG: nld buffer overflow: want to copy 132, max 64
After:
Error: Concatenation of size 544 exceeds maximum size of 512
udp length . @th,0,512 . @th,512,512 { 47-63 . 0xe373135363130 . 0x33131303735353203 }
^^^^^^^^^
resp. same warning for an over-sized raw expression.
Signed-off-by: Florian Westphal <fw@strlen.de>
Diffstat (limited to 'src/parser_bison.y')
| -rw-r--r-- | src/parser_bison.y | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/src/parser_bison.y b/src/parser_bison.y index 571eddf1..7082d2ba 100644 --- a/src/parser_bison.y +++ b/src/parser_bison.y @@ -5627,6 +5627,13 @@ payload_expr : payload_raw_expr payload_raw_expr : AT payload_base_spec COMMA NUM COMMA NUM close_scope_at { + if ($6 > NFT_MAX_EXPR_LEN_BITS) { + erec_queue(error(&@1, "raw payload length %u exceeds upper limit of %u", + $6, NFT_MAX_EXPR_LEN_BITS), + state->msgs); + YYERROR; + } + $$ = payload_expr_alloc(&@$, NULL, 0); payload_init_raw($$, $2, $4, $6); $$->byteorder = BYTEORDER_BIG_ENDIAN; |