From: Masami Hiramatsu (Google) Date: Thu, 5 Feb 2026 00:46:25 +0000 (+0900) Subject: bootconfig: Terminate value search if it hits a newline X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1cadf2819bc91ab5cb060ec3ce473bae30c9e52d;p=thirdparty%2Fkernel%2Fstable.git bootconfig: Terminate value search if it hits a newline Terminate the value search for a key if it hits a newline and make the value empty. When we pass a bootconfig with an empty value terminated by the newline, like below:: foo = bar = value Current bootconfig interprets it as a single entry:: foo = "bar = value"; The Documentation/admin-guide/bootconfig.rst defines the value itself is terminated by newline: The value has to be terminated by semi-colon (``;``) or newline (``\n``). but it does not define when the value search is terminated. This changes the behavior to be more line-oriented, so that it is clearer in how it works. - The value search of key-value pair will be terminated by a comment or newline. - The value search of an array will continue beyond comments and newlines. Thus, with this update, the above example is interpreted as:: foo = ""; bar = "value"; And the below example will cause a syntax error because "bar" is expected as a key but it has ','. foo = bar, buz According to this change, one wrong example config is updated. Link: https://lore.kernel.org/all/177025238503.14982.17059549076175612447.stgit@devnote2/ Signed-off-by: Masami Hiramatsu (Google) Reviewed-by: Julius Werner --- diff --git a/Documentation/admin-guide/bootconfig.rst b/Documentation/admin-guide/bootconfig.rst index 7a86042c9b6da..f712758472d5c 100644 --- a/Documentation/admin-guide/bootconfig.rst +++ b/Documentation/admin-guide/bootconfig.rst @@ -20,18 +20,26 @@ Config File Syntax The boot config syntax is a simple structured key-value. Each key consists of dot-connected-words, and key and value are connected by ``=``. The value -has to be terminated by semi-colon (``;``) or newline (``\n``). -For array value, array entries are separated by comma (``,``). :: - - KEY[.WORD[...]] = VALUE[, VALUE2[...]][;] - -Unlike the kernel command line syntax, spaces are OK around the comma and ``=``. +string has to be terminated by the following delimiters described below. Each key word must contain only alphabets, numbers, dash (``-``) or underscore (``_``). And each value only contains printable characters or spaces except for delimiters such as semi-colon (``;``), new-line (``\n``), comma (``,``), hash (``#``) and closing brace (``}``). +If the ``=`` is followed by whitespace up to one of these delimiters, the +key is assigned an empty value. + +For arrays, the array values are comma (``,``) separated, and comments and +line breaks with newline (``\n``) are allowed between array values for +readability. Thus the first entry of the array must be on the same line as +the key.:: + + KEY[.WORD[...]] = VALUE[, VALUE2[...]][;] + +Unlike the kernel command line syntax, white spaces (including tabs) are +ignored around the comma and ``=``. + If you want to use those delimiters in a value, you can use either double- quotes (``"VALUE"``) or single-quotes (``'VALUE'``) to quote it. Note that you can not escape these quotes. @@ -138,8 +146,8 @@ This is parsed as below:: foo = value bar = 1, 2, 3 -Note that you can not put a comment between value and delimiter(``,`` or -``;``). This means following config has a syntax error :: +Note that you can NOT put a comment or a newline between value and delimiter +(``,`` or ``;``). This means following config has a syntax error :: key = 1 # comment ,2 diff --git a/lib/bootconfig.c b/lib/bootconfig.c index 81f29c29f47b6..449369a608461 100644 --- a/lib/bootconfig.c +++ b/lib/bootconfig.c @@ -557,17 +557,13 @@ static int __init __xbc_close_brace(char *p) /* * Return delimiter or error, no node added. As same as lib/cmdline.c, * you can use " around spaces, but can't escape " for value. + * *@__v must point real value string. (not including spaces before value.) */ static int __init __xbc_parse_value(char **__v, char **__n) { char *p, *v = *__v; int c, quotes = 0; - v = skip_spaces(v); - while (*v == '#') { - v = skip_comment(v); - v = skip_spaces(v); - } if (*v == '"' || *v == '\'') { quotes = *v; v++; @@ -617,6 +613,13 @@ static int __init xbc_parse_array(char **__v) last_parent = xbc_node_get_child(last_parent); do { + /* Search the next array value beyond comments and empty lines */ + next = skip_spaces(*__v); + while (*next == '#') { + next = skip_comment(next); + next = skip_spaces(next); + } + *__v = next; c = __xbc_parse_value(__v, &next); if (c < 0) return c; @@ -701,9 +704,17 @@ static int __init xbc_parse_kv(char **k, char *v, int op) if (ret) return ret; - c = __xbc_parse_value(&v, &next); - if (c < 0) - return c; + v = skip_spaces_until_newline(v); + /* If there is a comment, this has an empty value. */ + if (*v == '#') { + next = skip_comment(v); + *v = '\0'; + c = '\n'; + } else { + c = __xbc_parse_value(&v, &next); + if (c < 0) + return c; + } child = xbc_node_get_child(last_parent); if (child && xbc_node_is_value(child)) { diff --git a/tools/bootconfig/samples/bad-array-after-comment.bconf b/tools/bootconfig/samples/bad-array-after-comment.bconf new file mode 100644 index 0000000000000..fdb6d4e044471 --- /dev/null +++ b/tools/bootconfig/samples/bad-array-after-comment.bconf @@ -0,0 +1,4 @@ +# the first array value must be on the same line as the key +key = # comment + value1, + value2 diff --git a/tools/bootconfig/samples/bad-array-in-next-line.bconf b/tools/bootconfig/samples/bad-array-in-next-line.bconf new file mode 100644 index 0000000000000..95a99a3bde8c0 --- /dev/null +++ b/tools/bootconfig/samples/bad-array-in-next-line.bconf @@ -0,0 +1,4 @@ +# the first array value must be on the same line as the key +key = + value1, + value2 diff --git a/tools/bootconfig/samples/good-array-space-comment.bconf b/tools/bootconfig/samples/good-array-space-comment.bconf index 45b938dc06959..416fa2ed41095 100644 --- a/tools/bootconfig/samples/good-array-space-comment.bconf +++ b/tools/bootconfig/samples/good-array-space-comment.bconf @@ -1,4 +1,3 @@ -key = # comment - "value1", # comment1 +key = "value1", # comment1 "value2" , # comment2 "value3"