One problem of grab_file() is that it cannot distinguish the following two cases:
- I cannot read the file (the file does not exist, or read permission is not set) - It can read the file, but the file size is zero This is because grab_file() calls mmap(), which requires the mapped length is greater than 0. Hence, grab_file() fails for both cases. If an empty header file were included from a module that requires checksum calculation, the following warning would be printed: WARNING: modpost: could not open ...: Invalid argument An empty file is a valid source file, so it should not fail. Use read_text_file() instead. It can read a zero-length file. Then, parse_file() will succeed with doing nothing. Signed-off-by: Masahiro Yamada <[email protected]> --- Changes in v2: None scripts/mod/sumversion.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/scripts/mod/sumversion.c b/scripts/mod/sumversion.c index f9df0b1863f1..a1c7b0f4cd5a 100644 --- a/scripts/mod/sumversion.c +++ b/scripts/mod/sumversion.c @@ -258,10 +258,12 @@ static int parse_file(const char *fname, struct md4_ctx *md) char *file; unsigned long i, len; - file = grab_file(fname, &len); + file = read_text_file(fname); if (!file) return 0; + len = strlen(file); + for (i = 0; i < len; i++) { /* Collapse and ignore \ and CR. */ if (file[i] == '\\' && (i+1 < len) && file[i+1] == '\n') { @@ -287,7 +289,7 @@ static int parse_file(const char *fname, struct md4_ctx *md) add_char(file[i], md); } - release_file(file, len); + free(file); return 1; } /* Check whether the file is a static library or not */ -- 2.25.1
