The commit 66cc69e34e86a231 ("Fix: module signature vs tracepoints:
add new TAINT_UNSIGNED_MODULE") updated module_taint_flags() to
potentially print one more character. But it did not increase the
size of the corresponding buffers in m_show() and print_modules().We have recently done the same mistake when adding a taint flag for livepatching, see https://lkml.kernel.org/g/cfba2c823bb984690b73572aaae1db596b54a082.1472137475.git.jpoim...@redhat.com Let's convert the taint flags into enum and handle the buffer size almost automatically. It is not optimal because only few taint flags can be printed by module_taint_flags(). But better be on the safe side. IMHO, it is not worth the optimization and this is a good compromise. Signed-off-by: Petr Mladek <pmla...@suse.com> --- include/linux/kernel.h | 44 ++++++++++++++++++++++++-------------------- kernel/module.c | 8 ++++++-- kernel/panic.c | 4 ++-- 3 files changed, 32 insertions(+), 24 deletions(-) diff --git a/include/linux/kernel.h b/include/linux/kernel.h index d96a6118d26a..1809bc82b7a5 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -472,14 +472,10 @@ static inline void set_arch_panic_timeout(int timeout, int arch_default_timeout) if (panic_timeout == arch_default_timeout) panic_timeout = timeout; } -extern const char *print_tainted(void); enum lockdep_ok { LOCKDEP_STILL_OK, LOCKDEP_NOW_UNRELIABLE }; -extern void add_taint(unsigned flag, enum lockdep_ok); -extern int test_taint(unsigned flag); -extern unsigned long get_taint(void); extern int root_mountflags; extern bool early_boot_irqs_disabled; @@ -493,22 +489,30 @@ extern enum system_states { SYSTEM_RESTART, } system_state; -#define TAINT_PROPRIETARY_MODULE 0 -#define TAINT_FORCED_MODULE 1 -#define TAINT_CPU_OUT_OF_SPEC 2 -#define TAINT_FORCED_RMMOD 3 -#define TAINT_MACHINE_CHECK 4 -#define TAINT_BAD_PAGE 5 -#define TAINT_USER 6 -#define TAINT_DIE 7 -#define TAINT_OVERRIDDEN_ACPI_TABLE 8 -#define TAINT_WARN 9 -#define TAINT_CRAP 10 -#define TAINT_FIRMWARE_WORKAROUND 11 -#define TAINT_OOT_MODULE 12 -#define TAINT_UNSIGNED_MODULE 13 -#define TAINT_SOFTLOCKUP 14 -#define TAINT_LIVEPATCH 15 +enum taint_flags { + TAINT_PROPRIETARY_MODULE, /* 0 */ + TAINT_FORCED_MODULE, /* 1 */ + TAINT_CPU_OUT_OF_SPEC, /* 2 */ + TAINT_FORCED_RMMOD, /* 3 */ + TAINT_MACHINE_CHECK, /* 4 */ + TAINT_BAD_PAGE, /* 5 */ + TAINT_USER, /* 6 */ + TAINT_DIE, /* 7 */ + TAINT_OVERRIDDEN_ACPI_TABLE, /* 8 */ + TAINT_WARN, /* 9 */ + TAINT_CRAP, /* 10 */ + TAINT_FIRMWARE_WORKAROUND, /* 11 */ + TAINT_OOT_MODULE, /* 12 */ + TAINT_UNSIGNED_MODULE, /* 13 */ + TAINT_SOFTLOCKUP, /* 14 */ + TAINT_LIVEPATCH, /* 15 */ + TAINT_FLAGS_COUNT /* keep last! */ +}; + +extern const char *print_tainted(void); +extern void add_taint(enum taint_flags flag, enum lockdep_ok); +extern int test_taint(enum taint_flags flag); +extern unsigned long get_taint(void); extern const char hex_asc[]; #define hex_asc_lo(x) hex_asc[((x) & 0x0f)] diff --git a/kernel/module.c b/kernel/module.c index 529efae9f481..fb6c0d425b47 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -4036,6 +4036,10 @@ int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *, } #endif /* CONFIG_KALLSYMS */ +/* Maximum number of characters written by module_flags() */ +#define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4) + +/* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */ static char *module_flags(struct module *mod, char *buf) { int bx = 0; @@ -4080,7 +4084,7 @@ static void m_stop(struct seq_file *m, void *p) static int m_show(struct seq_file *m, void *p) { struct module *mod = list_entry(p, struct module, list); - char buf[8]; + char buf[MODULE_FLAGS_BUF_SIZE]; /* We always ignore unformed modules. */ if (mod->state == MODULE_STATE_UNFORMED) @@ -4251,7 +4255,7 @@ EXPORT_SYMBOL_GPL(__module_text_address); void print_modules(void) { struct module *mod; - char buf[8]; + char buf[MODULE_FLAGS_BUF_SIZE]; printk(KERN_DEFAULT "Modules linked in:"); /* Most callers should already have preempt disabled, but make sure */ diff --git a/kernel/panic.c b/kernel/panic.c index ca8cea1ef673..e90125bf9238 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -334,7 +334,7 @@ const char *print_tainted(void) return buf; } -int test_taint(unsigned flag) +int test_taint(enum taint_flags flag) { return test_bit(flag, &tainted_mask); } @@ -353,7 +353,7 @@ unsigned long get_taint(void) * If something bad has gone wrong, you'll want @lockdebug_ok = false, but for * some notewortht-but-not-corrupting cases, it can be set to true. */ -void add_taint(unsigned flag, enum lockdep_ok lockdep_ok) +void add_taint(enum taint_flags flag, enum lockdep_ok lockdep_ok) { if (lockdep_ok == LOCKDEP_NOW_UNRELIABLE && __debug_locks_off()) pr_warn("Disabling lock debugging due to kernel taint\n"); -- 1.8.5.6
