Re: [PATCH] dtc: ensure #line directives don't consume data from the next line

Ian Campbell
2013-06-03T16:02:56Z

On Mon, 2013-06-03 at 09:36 -0600, Stephen Warren wrote:
> From: Stephen Warren <swarren@nvidia.com>
>
> Previously, the #line parsing regex ended with ({WS}+[0-9]+)?. The {WS}
> could match line-break characters. If the #line directive did not contain
> the optional flags field at the end, this could cause any integer data on
> the next line to be consumed as part of the #line directive parsing. This
> could cause syntax errors (i.e. #line parsing consuming the leading 0
> from a hex literal 0x1234, leaving x1234 to be parsed as cell data,
> which is a syntax error), or invalid compilation results (i.e. simply
> consuming literal 1234 as part of the #line processing, thus removing it
> from the cell data).
>
> Fix this by replacing {WS} with [ \t] so that it can't match line-breaks.
>
> Convert all instances of {WS}, even though the other instances should be
> irrelevant for any well-formed #line directive. This is done for
> consistency and ultimate safety.
>
> This is a port of upstream dtc commit a1ee6f0 (with same subject) to the
> kernel's copy of dtc.

FWIW I have tested the upstream commit via my device-tree.git. If that
is considered sufficient then it is OK by me to apply
Tested-by: Ian Campbell <ian.campbell@citrix.com>
to this change too.

>
> Reported-by: Ian Campbell <Ian.Campbell@citrix.com>
> Signed-off-by: Stephen Warren <swarren@nvidia.com>
> ---
> This is a fix for 3.10.
>
> scripts/dtc/dtc-lexer.l | 2 +-
> scripts/dtc/dtc-lexer.lex.c_shipped | 232 +++++++++++++++++------------------
> 2 files changed, 117 insertions(+), 117 deletions(-)
>
> diff --git a/scripts/dtc/dtc-lexer.l b/scripts/dtc/dtc-lexer.l
> index 254d5af..3b41bfc 100644
> --- a/scripts/dtc/dtc-lexer.l
> +++ b/scripts/dtc/dtc-lexer.l
> @@ -71,7 +71,7 @@ static int pop_input_file(void);
> push_input_file(name);
> }
>
> -<*>^"#"(line)?{WS}+[0-9]+{WS}+{STRING}({WS}+[0-9]+)? {
> +<*>^"#"(line)?[ \t]+[0-9]+[ \t]+{STRING}([ \t]+[0-9]+)? {
> char *line, *tmp, *fn;
> /* skip text before line # */
> line = yytext;
> diff --git a/scripts/dtc/dtc-lexer.lex.c_shipped b/scripts/dtc/dtc-lexer.lex.c_shipped
> index a6c5fcd..2d30f41 100644
> --- a/scripts/dtc/dtc-lexer.lex.c_shipped
> +++ b/scripts/dtc/dtc-lexer.lex.c_shipped
> @@ -405,19 +405,19 @@ static yyconst flex_int16_t yy_accept[161] =
> static yyconst flex_int32_t yy_ec[256] =
> { 0,
> 1, 1, 1, 1, 1, 1, 1, 1, 2, 3,
> - 2, 2, 2, 1, 1, 1, 1, 1, 1, 1,
> + 4, 4, 4, 1, 1, 1, 1, 1, 1, 1,
> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
> - 1, 2, 4, 5, 6, 1, 1, 7, 8, 1,
> - 1, 9, 10, 10, 11, 10, 12, 13, 14, 15,
> - 15, 15, 15, 15, 15, 15, 15, 16, 1, 17,
> - 18, 19, 10, 10, 20, 20, 20, 20, 20, 20,
> - 21, 21, 21, 21, 21, 22, 21, 21, 21, 21,
> - 21, 21, 21, 21, 23, 21, 21, 24, 21, 21,
> - 1, 25, 26, 1, 21, 1, 20, 27, 28, 29,
> -
> - 30, 20, 21, 21, 31, 21, 21, 32, 33, 34,
> - 35, 36, 21, 37, 38, 39, 40, 41, 21, 24,
> - 42, 21, 43, 44, 45, 1, 1, 1, 1, 1,
> + 1, 2, 5, 6, 7, 1, 1, 8, 9, 1,
> + 1, 10, 11, 11, 12, 11, 13, 14, 15, 16,
> + 16, 16, 16, 16, 16, 16, 16, 17, 1, 18,
> + 19, 20, 11, 11, 21, 21, 21, 21, 21, 21,
> + 22, 22, 22, 22, 22, 23, 22, 22, 22, 22,
> + 22, 22, 22, 22, 24, 22, 22, 25, 22, 22,
> + 1, 26, 27, 1, 22, 1, 21, 28, 29, 30,
> +
> + 31, 21, 22, 22, 32, 22, 22, 33, 34, 35,
> + 36, 37, 22, 38, 39, 40, 41, 42, 22, 25,
> + 43, 22, 44, 45, 46, 1, 1, 1, 1, 1,
> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
> @@ -434,36 +434,36 @@ static yyconst flex_int32_t yy_ec[256] =
> 1, 1, 1, 1, 1
> } ;
>
> -static yyconst flex_int32_t yy_meta[46] =
> +static yyconst flex_int32_t yy_meta[47] =
> { 0,
> - 1, 1, 1, 1, 1, 2, 3, 1, 2, 2,
> - 2, 4, 5, 5, 5, 6, 1, 1, 1, 7,
> - 8, 8, 8, 8, 1, 1, 7, 7, 7, 7,
> - 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
> - 8, 8, 3, 1, 1
> + 1, 1, 1, 1, 1, 1, 2, 3, 1, 2,
> + 2, 2, 4, 5, 5, 5, 6, 1, 1, 1,
> + 7, 8, 8, 8, 8, 1, 1, 7, 7, 7,
> + 7, 8, 8, 8, 8, 8, 8, 8, 8, 8,
> + 8, 8, 8, 3, 1, 1
> } ;
>
> static yyconst flex_int16_t yy_base[175] =
> { 0,
> - 0, 388, 381, 40, 41, 386, 71, 385, 34, 44,
> - 390, 395, 60, 62, 371, 112, 111, 111, 111, 104,
> - 370, 106, 371, 342, 124, 119, 0, 144, 395, 0,
> - 123, 0, 159, 153, 165, 167, 395, 130, 395, 382,
> - 395, 0, 372, 122, 395, 157, 374, 379, 350, 21,
> - 346, 349, 395, 395, 395, 395, 395, 362, 395, 395,
> - 181, 346, 342, 395, 359, 0, 191, 343, 190, 351,
> - 350, 0, 0, 0, 173, 362, 177, 367, 357, 329,
> - 335, 328, 337, 331, 206, 329, 334, 327, 395, 338,
> - 170, 314, 346, 345, 318, 325, 343, 158, 316, 212,
> -
> - 322, 319, 320, 395, 340, 336, 308, 305, 314, 304,
> - 295, 138, 208, 220, 395, 292, 305, 265, 264, 254,
> - 201, 222, 285, 275, 273, 270, 236, 235, 225, 115,
> - 395, 395, 252, 216, 216, 217, 214, 230, 209, 220,
> - 213, 239, 211, 217, 216, 209, 229, 395, 240, 225,
> - 206, 169, 395, 395, 116, 106, 99, 54, 395, 395,
> - 254, 260, 268, 272, 276, 282, 289, 293, 301, 309,
> - 313, 319, 327, 335
> + 0, 385, 378, 40, 41, 383, 72, 382, 34, 44,
> + 388, 393, 61, 117, 368, 116, 115, 115, 115, 48,
> + 367, 107, 368, 339, 127, 120, 0, 147, 393, 0,
> + 127, 0, 133, 156, 168, 153, 393, 125, 393, 380,
> + 393, 0, 369, 127, 393, 160, 371, 377, 347, 21,
> + 343, 346, 393, 393, 393, 393, 393, 359, 393, 393,
> + 183, 343, 339, 393, 356, 0, 183, 340, 187, 348,
> + 347, 0, 0, 0, 178, 359, 195, 365, 354, 326,
> + 332, 325, 334, 328, 204, 326, 331, 324, 393, 335,
> + 150, 311, 343, 342, 315, 322, 340, 179, 313, 207,
> +
> + 319, 316, 317, 393, 337, 333, 305, 302, 311, 301,
> + 310, 190, 338, 337, 393, 307, 322, 301, 305, 277,
> + 208, 311, 307, 278, 271, 270, 248, 246, 213, 130,
> + 393, 393, 263, 235, 207, 221, 218, 229, 213, 213,
> + 206, 234, 218, 210, 208, 193, 219, 393, 223, 204,
> + 176, 157, 393, 393, 120, 106, 97, 119, 393, 393,
> + 245, 251, 259, 263, 267, 273, 280, 284, 292, 300,
> + 304, 310, 318, 326
> } ;
>
> static yyconst flex_int16_t yy_def[175] =
> @@ -489,108 +489,108 @@ static yyconst flex_int16_t yy_def[175] =
> 160, 160, 160, 160
> } ;
>
> -static yyconst flex_int16_t yy_nxt[441] =
> +static yyconst flex_int16_t yy_nxt[440] =
> { 0,
> - 12, 13, 14, 15, 16, 12, 17, 18, 12, 12,
> - 12, 19, 12, 12, 12, 12, 20, 21, 22, 23,
> - 23, 23, 23, 23, 12, 12, 23, 23, 23, 23,
> + 12, 13, 14, 13, 15, 16, 12, 17, 18, 12,
> + 12, 12, 19, 12, 12, 12, 12, 20, 21, 22,
> + 23, 23, 23, 23, 23, 12, 12, 23, 23, 23,
> 23, 23, 23, 23, 23, 23, 23, 23, 23, 23,
> - 23, 23, 12, 24, 12, 25, 34, 35, 35, 25,
> - 81, 26, 26, 27, 27, 27, 34, 35, 35, 82,
> - 28, 36, 36, 36, 36, 159, 29, 28, 28, 28,
> - 28, 12, 13, 14, 15, 16, 30, 17, 18, 30,
> - 30, 30, 26, 30, 30, 30, 12, 20, 21, 22,
> - 31, 31, 31, 31, 31, 32, 12, 31, 31, 31,
> + 23, 23, 23, 12, 24, 12, 25, 34, 35, 35,
> + 25, 81, 26, 26, 27, 27, 27, 34, 35, 35,
> + 82, 28, 36, 36, 36, 53, 54, 29, 28, 28,
> + 28, 28, 12, 13, 14, 13, 15, 16, 30, 17,
> + 18, 30, 30, 30, 26, 30, 30, 30, 12, 20,
> + 21, 22, 31, 31, 31, 31, 31, 32, 12, 31,
>
> 31, 31, 31, 31, 31, 31, 31, 31, 31, 31,
> - 31, 31, 31, 12, 24, 12, 39, 41, 45, 47,
> - 53, 54, 48, 56, 57, 61, 61, 47, 66, 45,
> - 48, 66, 66, 66, 39, 46, 40, 49, 59, 50,
> - 158, 51, 122, 52, 157, 49, 46, 50, 136, 63,
> - 137, 52, 156, 43, 40, 62, 65, 65, 65, 59,
> - 61, 61, 123, 65, 75, 69, 69, 69, 36, 36,
> - 65, 65, 65, 65, 70, 71, 72, 69, 69, 69,
> - 45, 46, 61, 61, 109, 77, 70, 71, 93, 110,
> - 68, 70, 71, 85, 85, 85, 66, 46, 155, 66,
> -
> - 66, 66, 69, 69, 69, 122, 59, 100, 100, 61,
> - 61, 70, 71, 100, 100, 148, 112, 154, 85, 85,
> - 85, 61, 61, 129, 129, 123, 129, 129, 135, 135,
> - 135, 142, 142, 148, 143, 149, 153, 135, 135, 135,
> - 142, 142, 160, 143, 152, 151, 150, 146, 145, 144,
> - 141, 140, 139, 149, 38, 38, 38, 38, 38, 38,
> - 38, 38, 42, 138, 134, 133, 42, 42, 44, 44,
> - 44, 44, 44, 44, 44, 44, 58, 58, 58, 58,
> - 64, 132, 64, 66, 131, 130, 66, 160, 66, 66,
> - 67, 128, 127, 67, 67, 67, 67, 73, 126, 73,
> -
> - 73, 76, 76, 76, 76, 76, 76, 76, 76, 78,
> - 78, 78, 78, 78, 78, 78, 78, 91, 125, 91,
> - 92, 124, 92, 92, 120, 92, 92, 121, 121, 121,
> - 121, 121, 121, 121, 121, 147, 147, 147, 147, 147,
> - 147, 147, 147, 119, 118, 117, 116, 115, 47, 114,
> - 110, 113, 111, 108, 107, 106, 48, 105, 104, 89,
> - 103, 102, 101, 99, 98, 97, 96, 95, 94, 79,
> - 77, 90, 89, 88, 59, 87, 86, 59, 84, 83,
> - 80, 79, 77, 74, 160, 60, 59, 55, 37, 160,
> - 33, 25, 26, 25, 11, 160, 160, 160, 160, 160,
> + 31, 31, 31, 31, 31, 12, 24, 12, 36, 36,
> + 36, 39, 41, 45, 47, 56, 57, 48, 61, 47,
> + 39, 159, 48, 66, 61, 45, 66, 66, 66, 158,
> + 46, 40, 49, 59, 50, 157, 51, 49, 52, 50,
> + 40, 63, 46, 52, 36, 36, 36, 156, 43, 62,
> + 65, 65, 65, 59, 136, 68, 137, 65, 75, 69,
> + 69, 69, 70, 71, 65, 65, 65, 65, 70, 71,
> + 72, 69, 69, 69, 61, 46, 45, 155, 154, 66,
> + 70, 71, 66, 66, 66, 122, 85, 85, 85, 59,
> +
> + 69, 69, 69, 46, 77, 100, 109, 93, 100, 70,
> + 71, 110, 112, 122, 129, 123, 153, 85, 85, 85,
> + 135, 135, 135, 148, 148, 160, 135, 135, 135, 152,
> + 142, 142, 142, 123, 143, 142, 142, 142, 151, 143,
> + 150, 146, 145, 149, 149, 38, 38, 38, 38, 38,
> + 38, 38, 38, 42, 144, 141, 140, 42, 42, 44,
> + 44, 44, 44, 44, 44, 44, 44, 58, 58, 58,
> + 58, 64, 139, 64, 66, 138, 134, 66, 133, 66,
> + 66, 67, 132, 131, 67, 67, 67, 67, 73, 130,
> + 73, 73, 76, 76, 76, 76, 76, 76, 76, 76,
> +
> + 78, 78, 78, 78, 78, 78, 78, 78, 91, 160,
> + 91, 92, 129, 92, 92, 128, 92, 92, 121, 121,
> + 121, 121, 121, 121, 121, 121, 147, 147, 147, 147,
> + 147, 147, 147, 147, 127, 126, 125, 124, 61, 61,
> + 120, 119, 118, 117, 116, 115, 47, 114, 110, 113,
> + 111, 108, 107, 106, 48, 105, 104, 89, 103, 102,
> + 101, 99, 98, 97, 96, 95, 94, 79, 77, 90,
> + 89, 88, 59, 87, 86, 59, 84, 83, 80, 79,
> + 77, 74, 160, 60, 59, 55, 37, 160, 33, 25,
> + 26, 25, 11, 160, 160, 160, 160, 160, 160, 160,
>
> 160, 160, 160, 160, 160, 160, 160, 160, 160, 160,
> 160, 160, 160, 160, 160, 160, 160, 160, 160, 160,
> 160, 160, 160, 160, 160, 160, 160, 160, 160, 160,
> - 160, 160, 160, 160, 160, 160, 160, 160, 160, 160
> + 160, 160, 160, 160, 160, 160, 160, 160, 160
> } ;
>
> -static yyconst flex_int16_t yy_chk[441] =
> +static yyconst flex_int16_t yy_chk[440] =
> { 0,
> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
> - 1, 1, 1, 1, 1, 4, 9, 9, 9, 10,
> - 50, 4, 5, 5, 5, 5, 10, 10, 10, 50,
> - 5, 13, 13, 14, 14, 158, 5, 5, 5, 5,
> - 5, 7, 7, 7, 7, 7, 7, 7, 7, 7,
> + 1, 1, 1, 1, 1, 1, 4, 9, 9, 9,
> + 10, 50, 4, 5, 5, 5, 5, 10, 10, 10,
> + 50, 5, 13, 13, 13, 20, 20, 5, 5, 5,
> + 5, 5, 7, 7, 7, 7, 7, 7, 7, 7,
> 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
> 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
>
> 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
> - 7, 7, 7, 7, 7, 7, 16, 17, 18, 19,
> - 20, 20, 19, 22, 22, 25, 25, 26, 31, 44,
> - 26, 31, 31, 31, 38, 18, 16, 19, 31, 19,
> - 157, 19, 112, 19, 156, 26, 44, 26, 130, 26,
> - 130, 26, 155, 17, 38, 25, 28, 28, 28, 28,
> - 33, 33, 112, 28, 46, 34, 34, 34, 36, 36,
> - 28, 28, 28, 28, 34, 34, 34, 35, 35, 35,
> - 75, 46, 61, 61, 98, 77, 35, 35, 77, 98,
> - 33, 91, 91, 61, 61, 61, 67, 75, 152, 67,
> -
> - 67, 67, 69, 69, 69, 121, 67, 85, 85, 113,
> - 113, 69, 69, 100, 100, 143, 100, 151, 85, 85,
> - 85, 114, 114, 122, 122, 121, 129, 129, 135, 135,
> - 135, 138, 138, 147, 138, 143, 150, 129, 129, 129,
> - 142, 142, 149, 142, 146, 145, 144, 141, 140, 139,
> - 137, 136, 134, 147, 161, 161, 161, 161, 161, 161,
> - 161, 161, 162, 133, 128, 127, 162, 162, 163, 163,
> - 163, 163, 163, 163, 163, 163, 164, 164, 164, 164,
> - 165, 126, 165, 166, 125, 124, 166, 123, 166, 166,
> - 167, 120, 119, 167, 167, 167, 167, 168, 118, 168,
> -
> - 168, 169, 169, 169, 169, 169, 169, 169, 169, 170,
> - 170, 170, 170, 170, 170, 170, 170, 171, 117, 171,
> - 172, 116, 172, 172, 111, 172, 172, 173, 173, 173,
> - 173, 173, 173, 173, 173, 174, 174, 174, 174, 174,
> - 174, 174, 174, 110, 109, 108, 107, 106, 105, 103,
> - 102, 101, 99, 97, 96, 95, 94, 93, 92, 90,
> - 88, 87, 86, 84, 83, 82, 81, 80, 79, 78,
> - 76, 71, 70, 68, 65, 63, 62, 58, 52, 51,
> - 49, 48, 47, 43, 40, 24, 23, 21, 15, 11,
> - 8, 6, 3, 2, 160, 160, 160, 160, 160, 160,
> + 7, 7, 7, 7, 7, 7, 7, 7, 14, 14,
> + 14, 16, 17, 18, 19, 22, 22, 19, 25, 26,
> + 38, 158, 26, 31, 33, 44, 31, 31, 31, 157,
> + 18, 16, 19, 31, 19, 156, 19, 26, 19, 26,
> + 38, 26, 44, 26, 36, 36, 36, 155, 17, 25,
> + 28, 28, 28, 28, 130, 33, 130, 28, 46, 34,
> + 34, 34, 91, 91, 28, 28, 28, 28, 34, 34,
> + 34, 35, 35, 35, 61, 46, 75, 152, 151, 67,
> + 35, 35, 67, 67, 67, 112, 61, 61, 61, 67,
> +
> + 69, 69, 69, 75, 77, 85, 98, 77, 100, 69,
> + 69, 98, 100, 121, 129, 112, 150, 85, 85, 85,
> + 135, 135, 135, 143, 147, 149, 129, 129, 129, 146,
> + 138, 138, 138, 121, 138, 142, 142, 142, 145, 142,
> + 144, 141, 140, 143, 147, 161, 161, 161, 161, 161,
> + 161, 161, 161, 162, 139, 137, 136, 162, 162, 163,
> + 163, 163, 163, 163, 163, 163, 163, 164, 164, 164,
> + 164, 165, 134, 165, 166, 133, 128, 166, 127, 166,
> + 166, 167, 126, 125, 167, 167, 167, 167, 168, 124,
> + 168, 168, 169, 169, 169, 169, 169, 169, 169, 169,
> +
> + 170, 170, 170, 170, 170, 170, 170, 170, 171, 123,
> + 171, 172, 122, 172, 172, 120, 172, 172, 173, 173,
> + 173, 173, 173, 173, 173, 173, 174, 174, 174, 174,
> + 174, 174, 174, 174, 119, 118, 117, 116, 114, 113,
> + 111, 110, 109, 108, 107, 106, 105, 103, 102, 101,
> + 99, 97, 96, 95, 94, 93, 92, 90, 88, 87,
> + 86, 84, 83, 82, 81, 80, 79, 78, 76, 71,
> + 70, 68, 65, 63, 62, 58, 52, 51, 49, 48,
> + 47, 43, 40, 24, 23, 21, 15, 11, 8, 6,
> + 3, 2, 160, 160, 160, 160, 160, 160, 160, 160,
>
> 160, 160, 160, 160, 160, 160, 160, 160, 160, 160,
> 160, 160, 160, 160, 160, 160, 160, 160, 160, 160,
> 160, 160, 160, 160, 160, 160, 160, 160, 160, 160,
> - 160, 160, 160, 160, 160, 160, 160, 160, 160, 160
> + 160, 160, 160, 160, 160, 160, 160, 160, 160
> } ;
>
> static yy_state_type yy_last_accepting_state;