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When the symbol is not changeable, the code calls printf("%s\n", def), which leads to a segmentation fault on certain systems/libc implementations when passing a NULL pointer to %s. This patch adds a check to ensure 'def' is not NULL before printing. Additionally, it removes the redundant re-initialization of the 'line' buffer inside the !sym_is_changeable(sym) block, as it is already initialized at the beginning of the function. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Xingjing Deng --- scripts/kconfig/conf.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/scripts/kconfig/conf.c b/scripts/kconfig/conf.c index a7b44cd8a..2771bc84e 100644 --- a/scripts/kconfig/conf.c +++ b/scripts/kconfig/conf.c @@ -297,9 +297,7 @@ static int conf_askvalue(struct symbol *sym, const char *def) line[1] = 0; if (!sym_is_changeable(sym)) { - printf("%s\n", def); - line[0] = '\n'; - line[1] = 0; + printf("%s\n", def ? def : ""); return 0; } @@ -307,7 +305,7 @@ static int conf_askvalue(struct symbol *sym, const char *def) case oldconfig: case syncconfig: if (sym_has_value(sym)) { - printf("%s\n", def); + printf("%s\n", def ? def : ""); return 0; } /* fall through */ -- 2.25.1