| Message ID | 20240620211112.500465-1-elsk@google.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] kconfig: recursive checks drop file/lineno | expand |
On Fri, Jun 21, 2024 at 6:11 AM HONG Yifan <elsk@google.com> wrote: > > This prevents segfault when getting filename > and lineno in recursive checks. > > If the following snippet is found in Kconfig: > > [Test code 1] > > config FOO > tristate > depends on BAR > select BAR > help > foo config FOO bool depends on BAR select BAR is enough to produce this issue. > ... without BAR defined; then if one runs > `make tinyconfig`, there is a segfault. There is no need to provide the particular command because this issue occurs for any 'make *config' command. > > Kconfig:34:error: recursive dependency detected! > Kconfig:34: symbol FOO depends on BAR > make[4]: *** [scripts/kconfig/Makefile:85: allnoconfig] Segmentation fault > > This is because of the following. BAR is > a fake entry created by sym_lookup() with prop > being NULL. In the recursive check, there is a > NULL check for prop to fall back to > stack->sym->prop if stack->prop is NULL. However, > in this case, stack->sym points to the fake BAR > entry created by sym_lookup(), so prop is still > NULL. prop was then referenced without additional > NULL checks, causing segfault. Each line is too short. You can wrap lines around 70-columns. > > As the previous email thread suggests, the file > and lineno for select is also wrong: > > [Test code 2] > > config FOO > bool > > config BAR > bool > > config FOO > bool "FOO" > depends on BAR > select BAR > > $ make defconfig > *** Default configuration is based on 'x86_64_defconfig' > Kconfig:1:error: recursive dependency detected! > Kconfig:1: symbol FOO depends on BAR > Kconfig:4: symbol BAR is selected by FOO > [...] > > Kconfig:4 should be Kconfig:10. > > This patch deletes the wrong and segfault-prone > filename/lineno inference completely. With this > patch, Test code 1 yields: > > error: recursive dependency detected! > symbol FOO depends on BAR > symbol BAR is selected by FOO > > Link: https://lore.kernel.org/linux-kbuild/20240618185609.4096399-1-elsk@google.com/ > Signed-off-by: HONG Yifan <elsk@google.com> > > -- > v2: Delete all filenames/lineno completely as > suggested by masahiroy@kernel.org This will break 'make testconfig' because you did not adjust scripts/kconfig/tests/err_recursive_dep/expected_stderr I cleaned up the function a little more. Please adjust scripts/kconfig/tests/err_recursive_dep/expected_stderr and rebase the patch on top of this: https://lore.kernel.org/linux-kbuild/20240626182212.3758235-1-masahiroy@kernel.org/T/#t > --- > scripts/kconfig/symbol.c | 43 +++++++++++++++------------------------- > 1 file changed, 16 insertions(+), 27 deletions(-) > > diff --git a/scripts/kconfig/symbol.c b/scripts/kconfig/symbol.c > index 8df0a75f40b9..3974e46a8533 100644 > --- a/scripts/kconfig/symbol.c > +++ b/scripts/kconfig/symbol.c > @@ -1042,9 +1042,9 @@ static void sym_check_print_recursive(struct symbol *last_sym) > { > struct dep_stack *stack; > struct symbol *sym, *next_sym; > - struct menu *menu = NULL; > struct property *prop; > struct dep_stack cv_stack; > + enum prop_type type; > > if (sym_is_choice_value(last_sym)) { > dep_stack_insert(&cv_stack, last_sym); > @@ -1066,54 +1066,43 @@ static void sym_check_print_recursive(struct symbol *last_sym) > if (prop == NULL) > prop = stack->sym->prop; Please remove these two lines as well. It is useless for getting 'type'. > > - /* for choice values find the menu entry (used below) */ > - if (sym_is_choice(sym) || sym_is_choice_value(sym)) { > - for (prop = sym->prop; prop; prop = prop->next) { > - menu = prop->menu; > - if (prop->menu) > - break; > - } > - } > + if (prop == NULL) > + type = P_UNKNOWN; > + else > + type = prop->type; > + > if (stack->sym == last_sym) > - fprintf(stderr, "%s:%d:error: recursive dependency detected!\n", > - prop->filename, prop->lineno); > + fprintf(stderr, "error: recursive dependency detected!\n"); > > if (sym_is_choice(sym)) { > - fprintf(stderr, "%s:%d:\tchoice %s contains symbol %s\n", > - menu->filename, menu->lineno, > + fprintf(stderr, "\tchoice %s contains symbol %s\n", > sym->name ? sym->name : "<choice>", > next_sym->name ? next_sym->name : "<choice>"); > } else if (sym_is_choice_value(sym)) { > - fprintf(stderr, "%s:%d:\tsymbol %s is part of choice %s\n", > - menu->filename, menu->lineno, > + fprintf(stderr, "\tsymbol %s is part of choice %s\n", > sym->name ? sym->name : "<choice>", > next_sym->name ? next_sym->name : "<choice>"); > } else if (stack->expr == &sym->dir_dep.expr) { > - fprintf(stderr, "%s:%d:\tsymbol %s depends on %s\n", > - prop->filename, prop->lineno, > + fprintf(stderr, "\tsymbol %s depends on %s\n", > sym->name ? sym->name : "<choice>", > next_sym->name ? next_sym->name : "<choice>"); > } else if (stack->expr == &sym->rev_dep.expr) { > - fprintf(stderr, "%s:%d:\tsymbol %s is selected by %s\n", > - prop->filename, prop->lineno, > + fprintf(stderr, "\tsymbol %s is selected by %s\n", > sym->name ? sym->name : "<choice>", > next_sym->name ? next_sym->name : "<choice>"); > } else if (stack->expr == &sym->implied.expr) { > - fprintf(stderr, "%s:%d:\tsymbol %s is implied by %s\n", > - prop->filename, prop->lineno, > + fprintf(stderr, "\tsymbol %s is implied by %s\n", > sym->name ? sym->name : "<choice>", > next_sym->name ? next_sym->name : "<choice>"); > } else if (stack->expr) { > - fprintf(stderr, "%s:%d:\tsymbol %s %s value contains %s\n", > - prop->filename, prop->lineno, > + fprintf(stderr, "\tsymbol %s %s value contains %s\n", > sym->name ? sym->name : "<choice>", > - prop_get_type_name(prop->type), > + prop_get_type_name(type), > next_sym->name ? next_sym->name : "<choice>"); > } else { > - fprintf(stderr, "%s:%d:\tsymbol %s %s is visible depending on %s\n", > - prop->filename, prop->lineno, > + fprintf(stderr, "\tsymbol %s %s is visible depending on %s\n", > sym->name ? sym->name : "<choice>", > - prop_get_type_name(prop->type), > + prop_get_type_name(type), > next_sym->name ? next_sym->name : "<choice>"); > } > } > -- > 2.45.2.741.gdbec12cfda-goog > -- Best Regards Masahiro Yamada
diff --git a/scripts/kconfig/symbol.c b/scripts/kconfig/symbol.c index 8df0a75f40b9..3974e46a8533 100644 --- a/scripts/kconfig/symbol.c +++ b/scripts/kconfig/symbol.c @@ -1042,9 +1042,9 @@ static void sym_check_print_recursive(struct symbol *last_sym) { struct dep_stack *stack; struct symbol *sym, *next_sym; - struct menu *menu = NULL; struct property *prop; struct dep_stack cv_stack; + enum prop_type type; if (sym_is_choice_value(last_sym)) { dep_stack_insert(&cv_stack, last_sym); @@ -1066,54 +1066,43 @@ static void sym_check_print_recursive(struct symbol *last_sym) if (prop == NULL) prop = stack->sym->prop; - /* for choice values find the menu entry (used below) */ - if (sym_is_choice(sym) || sym_is_choice_value(sym)) { - for (prop = sym->prop; prop; prop = prop->next) { - menu = prop->menu; - if (prop->menu) - break; - } - } + if (prop == NULL) + type = P_UNKNOWN; + else + type = prop->type; + if (stack->sym == last_sym) - fprintf(stderr, "%s:%d:error: recursive dependency detected!\n", - prop->filename, prop->lineno); + fprintf(stderr, "error: recursive dependency detected!\n"); if (sym_is_choice(sym)) { - fprintf(stderr, "%s:%d:\tchoice %s contains symbol %s\n", - menu->filename, menu->lineno, + fprintf(stderr, "\tchoice %s contains symbol %s\n", sym->name ? sym->name : "<choice>", next_sym->name ? next_sym->name : "<choice>"); } else if (sym_is_choice_value(sym)) { - fprintf(stderr, "%s:%d:\tsymbol %s is part of choice %s\n", - menu->filename, menu->lineno, + fprintf(stderr, "\tsymbol %s is part of choice %s\n", sym->name ? sym->name : "<choice>", next_sym->name ? next_sym->name : "<choice>"); } else if (stack->expr == &sym->dir_dep.expr) { - fprintf(stderr, "%s:%d:\tsymbol %s depends on %s\n", - prop->filename, prop->lineno, + fprintf(stderr, "\tsymbol %s depends on %s\n", sym->name ? sym->name : "<choice>", next_sym->name ? next_sym->name : "<choice>"); } else if (stack->expr == &sym->rev_dep.expr) { - fprintf(stderr, "%s:%d:\tsymbol %s is selected by %s\n", - prop->filename, prop->lineno, + fprintf(stderr, "\tsymbol %s is selected by %s\n", sym->name ? sym->name : "<choice>", next_sym->name ? next_sym->name : "<choice>"); } else if (stack->expr == &sym->implied.expr) { - fprintf(stderr, "%s:%d:\tsymbol %s is implied by %s\n", - prop->filename, prop->lineno, + fprintf(stderr, "\tsymbol %s is implied by %s\n", sym->name ? sym->name : "<choice>", next_sym->name ? next_sym->name : "<choice>"); } else if (stack->expr) { - fprintf(stderr, "%s:%d:\tsymbol %s %s value contains %s\n", - prop->filename, prop->lineno, + fprintf(stderr, "\tsymbol %s %s value contains %s\n", sym->name ? sym->name : "<choice>", - prop_get_type_name(prop->type), + prop_get_type_name(type), next_sym->name ? next_sym->name : "<choice>"); } else { - fprintf(stderr, "%s:%d:\tsymbol %s %s is visible depending on %s\n", - prop->filename, prop->lineno, + fprintf(stderr, "\tsymbol %s %s is visible depending on %s\n", sym->name ? sym->name : "<choice>", - prop_get_type_name(prop->type), + prop_get_type_name(type), next_sym->name ? next_sym->name : "<choice>"); } }
This prevents segfault when getting filename and lineno in recursive checks. If the following snippet is found in Kconfig: [Test code 1] config FOO tristate depends on BAR select BAR help foo ... without BAR defined; then if one runs `make tinyconfig`, there is a segfault. Kconfig:34:error: recursive dependency detected! Kconfig:34: symbol FOO depends on BAR make[4]: *** [scripts/kconfig/Makefile:85: allnoconfig] Segmentation fault This is because of the following. BAR is a fake entry created by sym_lookup() with prop being NULL. In the recursive check, there is a NULL check for prop to fall back to stack->sym->prop if stack->prop is NULL. However, in this case, stack->sym points to the fake BAR entry created by sym_lookup(), so prop is still NULL. prop was then referenced without additional NULL checks, causing segfault. As the previous email thread suggests, the file and lineno for select is also wrong: [Test code 2] config FOO bool config BAR bool config FOO bool "FOO" depends on BAR select BAR $ make defconfig *** Default configuration is based on 'x86_64_defconfig' Kconfig:1:error: recursive dependency detected! Kconfig:1: symbol FOO depends on BAR Kconfig:4: symbol BAR is selected by FOO [...] Kconfig:4 should be Kconfig:10. This patch deletes the wrong and segfault-prone filename/lineno inference completely. With this patch, Test code 1 yields: error: recursive dependency detected! symbol FOO depends on BAR symbol BAR is selected by FOO Link: https://lore.kernel.org/linux-kbuild/20240618185609.4096399-1-elsk@google.com/ Signed-off-by: HONG Yifan <elsk@google.com> -- v2: Delete all filenames/lineno completely as suggested by masahiroy@kernel.org --- scripts/kconfig/symbol.c | 43 +++++++++++++++------------------------- 1 file changed, 16 insertions(+), 27 deletions(-)