| Message ID | 20180925001832.18322-20-keescook@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | LSM: Explict LSM ordering | expand |
On 09/24/2018 05:18 PM, Kees Cook wrote: > This moves the string handling for "security=" boot parameter into > a stored pointer instead of a string duplicate. This will allow > easier handling of the string when switching logic to use the coming > enable/disable infrastructure. > > Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: John Johansen <john.johansen@canonical.com> > --- > security/security.c | 17 ++++++++--------- > 1 file changed, 8 insertions(+), 9 deletions(-) > > diff --git a/security/security.c b/security/security.c > index 456a3f73bc36..e325fcc41f00 100644 > --- a/security/security.c > +++ b/security/security.c > @@ -34,18 +34,14 @@ > > #define MAX_LSM_EVM_XATTR 2 > > -/* Maximum number of letters for an LSM name string */ > -#define SECURITY_NAME_MAX 10 > - > struct security_hook_heads security_hook_heads __lsm_ro_after_init; > static ATOMIC_NOTIFIER_HEAD(lsm_notifier_chain); > > char *lsm_names; > /* Boot-time LSM user choice */ > -static __initdata char chosen_lsm[SECURITY_NAME_MAX + 1] = > - CONFIG_DEFAULT_SECURITY; > static __initdata const char *chosen_lsm_enable; > static __initdata const char *chosen_lsm_disable; > +static __initdata const char *chosen_major_lsm; > > static __initconst const char * const builtin_lsm_enable = CONFIG_LSM_ENABLE; > > @@ -112,7 +108,7 @@ static bool __init lsm_allowed(struct lsm_info *lsm) > return true; > > /* Disabled if this LSM isn't the chosen one. */ > - if (strcmp(lsm->name, chosen_lsm) != 0) > + if (strcmp(lsm->name, chosen_major_lsm) != 0) > return false; > > return true; > @@ -191,6 +187,9 @@ static void __init prepare_lsm_enable(void) > /* Process "lsm.enable=" and "lsm.disable=", if given. */ > parse_lsm_enable(chosen_lsm_enable, set_enabled, true); > parse_lsm_enable(chosen_lsm_disable, set_enabled, false); > + > + if (!chosen_major_lsm) > + chosen_major_lsm = CONFIG_DEFAULT_SECURITY; > } > > /** > @@ -231,12 +230,12 @@ int __init security_init(void) > } > > /* Save user chosen LSM */ > -static int __init choose_lsm(char *str) > +static int __init choose_major_lsm(char *str) > { > - strncpy(chosen_lsm, str, SECURITY_NAME_MAX); > + chosen_major_lsm = str; > return 1; > } > -__setup("security=", choose_lsm); > +__setup("security=", choose_major_lsm); > > /* Enable LSM order debugging. */ > static int __init enable_debug(char *str) >
diff --git a/security/security.c b/security/security.c index 456a3f73bc36..e325fcc41f00 100644 --- a/security/security.c +++ b/security/security.c @@ -34,18 +34,14 @@ #define MAX_LSM_EVM_XATTR 2 -/* Maximum number of letters for an LSM name string */ -#define SECURITY_NAME_MAX 10 - struct security_hook_heads security_hook_heads __lsm_ro_after_init; static ATOMIC_NOTIFIER_HEAD(lsm_notifier_chain); char *lsm_names; /* Boot-time LSM user choice */ -static __initdata char chosen_lsm[SECURITY_NAME_MAX + 1] = - CONFIG_DEFAULT_SECURITY; static __initdata const char *chosen_lsm_enable; static __initdata const char *chosen_lsm_disable; +static __initdata const char *chosen_major_lsm; static __initconst const char * const builtin_lsm_enable = CONFIG_LSM_ENABLE; @@ -112,7 +108,7 @@ static bool __init lsm_allowed(struct lsm_info *lsm) return true; /* Disabled if this LSM isn't the chosen one. */ - if (strcmp(lsm->name, chosen_lsm) != 0) + if (strcmp(lsm->name, chosen_major_lsm) != 0) return false; return true; @@ -191,6 +187,9 @@ static void __init prepare_lsm_enable(void) /* Process "lsm.enable=" and "lsm.disable=", if given. */ parse_lsm_enable(chosen_lsm_enable, set_enabled, true); parse_lsm_enable(chosen_lsm_disable, set_enabled, false); + + if (!chosen_major_lsm) + chosen_major_lsm = CONFIG_DEFAULT_SECURITY; } /** @@ -231,12 +230,12 @@ int __init security_init(void) } /* Save user chosen LSM */ -static int __init choose_lsm(char *str) +static int __init choose_major_lsm(char *str) { - strncpy(chosen_lsm, str, SECURITY_NAME_MAX); + chosen_major_lsm = str; return 1; } -__setup("security=", choose_lsm); +__setup("security=", choose_major_lsm); /* Enable LSM order debugging. */ static int __init enable_debug(char *str)
This moves the string handling for "security=" boot parameter into a stored pointer instead of a string duplicate. This will allow easier handling of the string when switching logic to use the coming enable/disable infrastructure. Signed-off-by: Kees Cook <keescook@chromium.org> --- security/security.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-)