diff options
author | Michael Braun <michael-dev@fami-braun.de> | 2020-05-01 17:48:18 +0200 |
---|---|---|
committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2020-05-01 22:31:54 +0200 |
commit | d2d226e1709338c11307ef757f7561bf25693649 (patch) | |
tree | d5cc64aa121cebf3c7933f4e13fe312a6d64a617 /src | |
parent | ea4dc28d696fb579848ba6c9cf5b042eba1d2d2d (diff) |
datatype: fix double-free resulting in use-after-free in datatype_free
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
Signed-off-by: Michael Braun <michael-dev@fami-braun.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'src')
-rw-r--r-- | src/datatype.c | 2 | ||||
-rw-r--r-- | src/expression.c | 2 |
2 files changed, 3 insertions, 1 deletions
diff --git a/src/datatype.c b/src/datatype.c index 095598d9..723ac649 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; 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; |