nft list table bridge t table bridge t { set s4 { typeof ip saddr . ip daddr elements = { 1.0.0.1 . 2.0.0.2 } } } ================================================================= ==24334==ERROR: AddressSanitizer: heap-use-after-free on address 0x6080000000a8 at pc 0x7fe0e67df0ad bp 0x7ffff83e88c0 sp 0x7ffff83e88b8 READ of size 4 at 0x6080000000a8 thread T0 #0 0x7fe0e67df0ac in datatype_free nftables/src/datatype.c:1110 #1 0x7fe0e67e2092 in expr_free nftables/src/expression.c:89 #2 0x7fe0e67a855e in set_free nftables/src/rule.c:359 #3 0x7fe0e67b2f3e in table_free nftables/src/rule.c:1263 #4 0x7fe0e67a70ce in __cache_flush nftables/src/rule.c:299 #5 0x7fe0e67a71c7 in cache_release nftables/src/rule.c:305 #6 0x7fe0e68dbfa9 in nft_ctx_free nftables/src/libnftables.c:292 #7 0x55f00fbe0051 in main nftables/src/main.c:469 #8 0x7fe0e553309a in __libc_start_main ../csu/libc-start.c:308 #9 0x55f00fbdd429 in _start (nftables/src/.libs/nft+0x9429) 0x6080000000a8 is located 8 bytes inside of 96-byte region [0x6080000000a0,0x608000000100) freed by thread T0 here: #0 0x7fe0e6e70fb0 in __interceptor_free (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xe8fb0) #1 0x7fe0e68b8122 in xfree nftables/src/utils.c:29 #2 0x7fe0e67df2e5 in datatype_free nftables/src/datatype.c:1117 #3 0x7fe0e67e2092 in expr_free nftables/src/expression.c:89 #4 0x7fe0e67a83fe in set_free nftables/src/rule.c:356 #5 0x7fe0e67b2f3e in table_free nftables/src/rule.c:1263 #6 0x7fe0e67a70ce in __cache_flush nftables/src/rule.c:299 #7 0x7fe0e67a71c7 in cache_release nftables/src/rule.c:305 #8 0x7fe0e68dbfa9 in nft_ctx_free nftables/src/libnftables.c:292 #9 0x55f00fbe0051 in main nftables/src/main.c:469 #10 0x7fe0e553309a in __libc_start_main ../csu/libc-start.c:308 previously allocated by thread T0 here: #0 0x7fe0e6e71330 in __interceptor_malloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xe9330) #1 0x7fe0e68b813d in xmalloc nftables/src/utils.c:36 #2 0x7fe0e68b8296 in xzalloc nftables/src/utils.c:65 #3 0x7fe0e67de7d5 in dtype_alloc nftables/src/datatype.c:1065 #4 0x7fe0e67df862 in concat_type_alloc nftables/src/datatype.c:1146 #5 0x7fe0e67ea852 in concat_expr_parse_udata nftables/src/expression.c:954 #6 0x7fe0e685dc94 in set_make_key nftables/src/netlink.c:718 #7 0x7fe0e685e177 in netlink_delinearize_set nftables/src/netlink.c:770 #8 0x7fe0e685f667 in list_set_cb nftables/src/netlink.c:895 #9 0x7fe0e4f95a03 in nftnl_set_list_foreach src/set.c:904 SUMMARY: AddressSanitizer: heap-use-after-free nftables/src/datatype.c:1110 in datatype_free Shadow bytes around the buggy address: 0x0c107fff7fc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0c107fff7fd0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0c107fff7fe0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0c107fff7ff0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0c107fff8000: fa fa fa fa fd fd fd fd fd fd fd fd fd fd fd fd =>0x0c107fff8010: fa fa fa fa fd[fd]fd fd fd fd fd fd fd fd fd fd 0x0c107fff8020: fa fa fa fa fd fd fd fd fd fd fd fd fd fd fd fd 0x0c107fff8030: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c107fff8040: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c107fff8050: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c107fff8060: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init order: f6 Poisoned by user: f7 Container overflow: fc Array cookie: ac Intra object redzone: bb ASan internal: fe Left alloca redzone: ca Right alloca redzone: cb ==24334==ABORTING --- src/datatype.c | 2 ++ src/expression.c | 2 +- 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/src/datatype.c b/src/datatype.c index 095598d9..0110846f 100644 --- a/src/datatype.c +++ b/src/datatype.c @@ -1083,6 +1083,8 @@ struct datatype *datatype_get(const struct datatype *ptr) void datatype_set(struct expr *expr, const struct datatype *dtype) { + if (dtype == expr->dtype) + return; // do not free dtype before incrementing refcnt again datatype_free(expr->dtype); expr->dtype = datatype_get(dtype); } diff --git a/src/expression.c b/src/expression.c index 6605beb3..a6bde70f 100644 --- a/src/expression.c +++ b/src/expression.c @@ -955,7 +955,7 @@ static struct expr *concat_expr_parse_udata(const struct nftnl_udata *attr) if (!dtype) goto err_free; - concat_expr->dtype = dtype; + concat_expr->dtype = datatype_get(dtype); concat_expr->len = dtype->size; return concat_expr; -- 2.20.1