From: Luka Koznjak Date: Wed, 4 Dec 2019 20:35:10 +0000 (+0100) Subject: file: fix segfault in uci_parse_config X-Git-Url: http://git.openwrt.org/?a=commitdiff_plain;h=aa5e77a13d955ac9b497efc015c957c475734f0d;hp=165b444131453d63fc78c1d86f23c3ca36a2ffd7;p=project%2Fuci.git file: fix segfault in uci_parse_config Fixed a segmentation fault caused by using a pointer to a reallocated address. The name pointer in the uci_parse_config function becomes invalid if assert_eol calls uci_realloc down the line, resulting in a segmentation fault when attempting to dereference name. A simple fix is to call assert_eol before retrieving the actual address for the name and type pointers. The segmentation fault has been found while fuzzing the uci configuration system for various types of different crashes and undefined behavious, which resulted in multiple different import files causing instability and sementation faults. Signed-off-by: Luka Kožnjak Signed-off-by: Juraj Vijtiuk CC: Luka Perkov --- diff --git a/file.c b/file.c index f5032bd..3cd7702 100644 --- a/file.c +++ b/file.c @@ -425,9 +425,9 @@ static void uci_parse_config(struct uci_context *ctx) uci_parse_error(ctx, "invalid character in type field"); ofs_name = next_arg(ctx, false, true, false); + assert_eol(ctx); type = pctx_str(pctx, ofs_type); name = pctx_str(pctx, ofs_name); - assert_eol(ctx); if (!name || !name[0]) { ctx->internal = !pctx->merge;