From 4a6795409d1520fd3da3e909a8bcf9d7fd0927bb Mon Sep 17 00:00:00 2001 From: Jo-Philipp Wich Date: Wed, 5 Aug 2020 09:07:00 +0200 Subject: base-files: functions.sh: fix config_get() on invalid identifiers When passing a section or option value to config_get() which contains characters that happen to be valid variable interpolation expressions, the function returns a nonsensical expression result instead of the expected empty string. When the passed section or option name contains other characters which are not valid within a shell variable name, a substitution error is occuring instead. The issue can be easily reproduced by one of the following examples: root@OpenWrt:~# . /lib/functions.sh root@OpenWrt:~# config load system root@OpenWrt:~# config_get variable invalid-section option root@OpenWrt:~# echo "$variable" section_option:- root@OpenWrt:~# . /lib/functions.sh root@OpenWrt:~# config load system root@OpenWrt:~# config_get variable section invalid-option root@OpenWrt:~# echo "$variable" option:- root@OpenWrt:~# . /lib/functions.sh root@OpenWrt:~# config load system root@OpenWrt:~# config_get variable section invalid@option -ash: eval: syntax error: bad substitution Fix this issue by only performing interpolations when the given section and option arguments are free of illegal characters. Signed-off-by: Jo-Philipp Wich --- package/base-files/files/lib/functions.sh | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) (limited to 'package/base-files/files') diff --git a/package/base-files/files/lib/functions.sh b/package/base-files/files/lib/functions.sh index 323e057451..7da0c872fa 100755 --- a/package/base-files/files/lib/functions.sh +++ b/package/base-files/files/lib/functions.sh @@ -107,9 +107,14 @@ config_unset() { # config_get