From bc2afbde9eae491bcef23ef5b24b25c7605ad911 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Tue, 12 Dec 2023 15:01:17 +0100 Subject: expr: fix buffer overflows in data value setters The data value setters memcpy() to a fixed-size buffer, but its very easy to make nft pass too-larger values. Example: @th,160,1272 gt 0 ERROR: AddressSanitizer: heap-buffer-overflow on address 0x60b000[..] Truncate the copy instead of corrupting the heap. This needs additional fixes on nft side to reject such statements with a proper error message. Signed-off-by: Florian Westphal --- src/expr/immediate.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'src/expr/immediate.c') diff --git a/src/expr/immediate.c b/src/expr/immediate.c index 5d477a8..f56aa8f 100644 --- a/src/expr/immediate.c +++ b/src/expr/immediate.c @@ -36,9 +36,7 @@ nftnl_expr_immediate_set(struct nftnl_expr *e, uint16_t type, memcpy(&imm->dreg, data, sizeof(imm->dreg)); break; case NFTNL_EXPR_IMM_DATA: - memcpy(&imm->data.val, data, data_len); - imm->data.len = data_len; - break; + return nftnl_data_cpy(&imm->data, data, data_len); case NFTNL_EXPR_IMM_VERDICT: memcpy(&imm->data.verdict, data, sizeof(imm->data.verdict)); break; -- cgit v1.2.3