On Sun, Oct 13, 2024 at 10:11 PM Elena Salomatkina
<esalomatkina@xxxxxxxxx> wrote:
>
> strsep() modifies its first argument - buf.
> If an error occurs in the parsing loop, an invalid pointer
> will be passed to the free() function.
> Make the pointer passed to free() match the return value of
> read_text_file().
>
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
>
> Fixes: 9413e7640564 ("kbuild: split the second line of *.mod into *.usyms")
> Signed-off-by: Elena Salomatkina <esalomatkina@xxxxxxxxx>
Thanks for spotting this.
This is a bike-shed, but please use 'p' or 'pos' as
the moving pointer and keep the 'buf'.
This is consistent with the following functions:
extract_crcs_for_object()
mod_set_crcs()
handle_white_list_exports()
read_dump()
parse_source_files()
> ---
> scripts/mod/sumversion.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/scripts/mod/sumversion.c b/scripts/mod/sumversion.c
> index 6bf9caca0968..03774957d8b9 100644
> --- a/scripts/mod/sumversion.c
> +++ b/scripts/mod/sumversion.c
> @@ -385,7 +385,7 @@ static int parse_source_files(const char *objfile, struct md4_ctx *md)
> /* Calc and record src checksum. */
> void get_src_version(const char *modname, char sum[], unsigned sumlen)
> {
> - char *buf;
> + char *buf, *orig;
> struct md4_ctx md;
> char *fname;
> char filelist[PATH_MAX + 1];
> @@ -393,7 +393,7 @@ void get_src_version(const char *modname, char sum[], unsigned sumlen)
> /* objects for a module are listed in the first line of *.mod file. */
> snprintf(filelist, sizeof(filelist), "%s.mod", modname);
>
> - buf = read_text_file(filelist);
> + orig = buf = read_text_file(filelist);
>
> md4_init(&md);
> while ((fname = strsep(&buf, "\n"))) {
> @@ -406,5 +406,5 @@ void get_src_version(const char *modname, char sum[], unsigned sumlen)
>
> md4_final_ascii(&md, sum, sumlen);
> free:
> - free(buf);
> + free(orig);
> }
> --
> 2.33.0
>
>
--
Best Regards
Masahiro Yamada
