| Message ID | 20230116085818.165539-8-konstantin.meskhidze@huawei.com (mailing list archive) |
|---|---|
| State | Handled Elsewhere |
| Headers | show |
| Series | Network support for Landlock | expand |
On 16/01/2023 09:58, Konstantin Meskhidze wrote: > Change the landlock_add_rule() syscall to support new rule types > in future Landlock versions. Add the add_rule_path_beneath() helper > to support current filesystem rules. > > Signed-off-by: Konstantin Meskhidze <konstantin.meskhidze@huawei.com> > --- > > Changes since v8: > * Refactors commit message. > * Minor fixes. > > Changes since v7: > * None > > Changes since v6: > * None > > Changes since v5: > * Refactors syscall landlock_add_rule() and add_rule_path_beneath() helper > to make argument check ordering consistent and get rid of partial revertings > in following patches. > * Rolls back refactoring base_test.c seltest. > * Formats code with clang-format-14. > > Changes since v4: > * Refactors add_rule_path_beneath() and landlock_add_rule() functions > to optimize code usage. > * Refactors base_test.c seltest: adds LANDLOCK_RULE_PATH_BENEATH > rule type in landlock_add_rule() call. > > Changes since v3: > * Split commit. > * Refactors landlock_add_rule syscall. > > --- > security/landlock/syscalls.c | 94 +++++++++++++++++++----------------- > 1 file changed, 50 insertions(+), 44 deletions(-) > > diff --git a/security/landlock/syscalls.c b/security/landlock/syscalls.c > index d35cd5d304db..73c80cd2cdbe 100644 > --- a/security/landlock/syscalls.c > +++ b/security/landlock/syscalls.c > @@ -274,6 +274,49 @@ static int get_path_from_fd(const s32 fd, struct path *const path) > return err; > } > > +static int add_rule_path_beneath(struct landlock_ruleset *const ruleset, > + const void __user *const rule_attr) > +{ > + struct landlock_path_beneath_attr path_beneath_attr; > + struct path path; > + int res, err; > + access_mask_t mask; > + > + /* Copies raw user space buffer, only one type for now. */ > + res = copy_from_user(&path_beneath_attr, rule_attr, > + sizeof(path_beneath_attr)); > + if (res) > + return -EFAULT; > + > + /* > + * Informs about useless rule: empty allowed_access (i.e. deny rules) > + * are ignored in path walks. > + */ > + if (!path_beneath_attr.allowed_access) { > + return -ENOMSG; > + } Please follows the ./scripts/checkpatch.pl conventions (i.e. no curly braces). You should add an empty line after this return though. > + /* > + * Checks that allowed_access matches the @ruleset constraints > + * (ruleset->access_masks[0] is automatically upgraded to 64-bits). > + */ > + mask = landlock_get_raw_fs_access_mask(ruleset, 0); > + if ((path_beneath_attr.allowed_access | mask) != mask) { > + return -EINVAL; > + } Same here. > + > + /* Gets and checks the new rule. */ > + err = get_path_from_fd(path_beneath_attr.parent_fd, &path); > + if (err) > + return err; > + > + /* Imports the new rule. */ > + err = landlock_append_fs_rule(ruleset, &path, > + path_beneath_attr.allowed_access); > + path_put(&path); > + No need for this empty line. > + return err; > +} > +
2/10/2023 8:38 PM, Mickaël Salaün пишет: > > On 16/01/2023 09:58, Konstantin Meskhidze wrote: >> Change the landlock_add_rule() syscall to support new rule types >> in future Landlock versions. Add the add_rule_path_beneath() helper >> to support current filesystem rules. >> >> Signed-off-by: Konstantin Meskhidze <konstantin.meskhidze@huawei.com> >> --- >> >> Changes since v8: >> * Refactors commit message. >> * Minor fixes. >> >> Changes since v7: >> * None >> >> Changes since v6: >> * None >> >> Changes since v5: >> * Refactors syscall landlock_add_rule() and add_rule_path_beneath() helper >> to make argument check ordering consistent and get rid of partial revertings >> in following patches. >> * Rolls back refactoring base_test.c seltest. >> * Formats code with clang-format-14. >> >> Changes since v4: >> * Refactors add_rule_path_beneath() and landlock_add_rule() functions >> to optimize code usage. >> * Refactors base_test.c seltest: adds LANDLOCK_RULE_PATH_BENEATH >> rule type in landlock_add_rule() call. >> >> Changes since v3: >> * Split commit. >> * Refactors landlock_add_rule syscall. >> >> --- >> security/landlock/syscalls.c | 94 +++++++++++++++++++----------------- >> 1 file changed, 50 insertions(+), 44 deletions(-) >> >> diff --git a/security/landlock/syscalls.c b/security/landlock/syscalls.c >> index d35cd5d304db..73c80cd2cdbe 100644 >> --- a/security/landlock/syscalls.c >> +++ b/security/landlock/syscalls.c >> @@ -274,6 +274,49 @@ static int get_path_from_fd(const s32 fd, struct path *const path) >> return err; >> } >> >> +static int add_rule_path_beneath(struct landlock_ruleset *const ruleset, >> + const void __user *const rule_attr) >> +{ >> + struct landlock_path_beneath_attr path_beneath_attr; >> + struct path path; >> + int res, err; >> + access_mask_t mask; >> + >> + /* Copies raw user space buffer, only one type for now. */ >> + res = copy_from_user(&path_beneath_attr, rule_attr, >> + sizeof(path_beneath_attr)); >> + if (res) >> + return -EFAULT; >> + >> + /* >> + * Informs about useless rule: empty allowed_access (i.e. deny rules) >> + * are ignored in path walks. >> + */ >> + if (!path_beneath_attr.allowed_access) { >> + return -ENOMSG; >> + } > > Please follows the ./scripts/checkpatch.pl conventions (i.e. no curly > braces). You should add an empty line after this return though. > Ok. I will fix it. > > >> + /* >> + * Checks that allowed_access matches the @ruleset constraints >> + * (ruleset->access_masks[0] is automatically upgraded to 64-bits). >> + */ >> + mask = landlock_get_raw_fs_access_mask(ruleset, 0); >> + if ((path_beneath_attr.allowed_access | mask) != mask) { >> + return -EINVAL; >> + } > > Same here. Got it. > >> + >> + /* Gets and checks the new rule. */ >> + err = get_path_from_fd(path_beneath_attr.parent_fd, &path); >> + if (err) >> + return err; >> + >> + /* Imports the new rule. */ >> + err = landlock_append_fs_rule(ruleset, &path, >> + path_beneath_attr.allowed_access); >> + path_put(&path); >> + > > No need for this empty line. Ok. Thanks for noticing. > >> + return err; >> +} >> + > .
diff --git a/security/landlock/syscalls.c b/security/landlock/syscalls.c index d35cd5d304db..73c80cd2cdbe 100644 --- a/security/landlock/syscalls.c +++ b/security/landlock/syscalls.c @@ -274,6 +274,49 @@ static int get_path_from_fd(const s32 fd, struct path *const path) return err; } +static int add_rule_path_beneath(struct landlock_ruleset *const ruleset, + const void __user *const rule_attr) +{ + struct landlock_path_beneath_attr path_beneath_attr; + struct path path; + int res, err; + access_mask_t mask; + + /* Copies raw user space buffer, only one type for now. */ + res = copy_from_user(&path_beneath_attr, rule_attr, + sizeof(path_beneath_attr)); + if (res) + return -EFAULT; + + /* + * Informs about useless rule: empty allowed_access (i.e. deny rules) + * are ignored in path walks. + */ + if (!path_beneath_attr.allowed_access) { + return -ENOMSG; + } + /* + * Checks that allowed_access matches the @ruleset constraints + * (ruleset->access_masks[0] is automatically upgraded to 64-bits). + */ + mask = landlock_get_raw_fs_access_mask(ruleset, 0); + if ((path_beneath_attr.allowed_access | mask) != mask) { + return -EINVAL; + } + + /* Gets and checks the new rule. */ + err = get_path_from_fd(path_beneath_attr.parent_fd, &path); + if (err) + return err; + + /* Imports the new rule. */ + err = landlock_append_fs_rule(ruleset, &path, + path_beneath_attr.allowed_access); + path_put(&path); + + return err; +} + /** * sys_landlock_add_rule - Add a new rule to a ruleset * @@ -306,11 +349,8 @@ SYSCALL_DEFINE4(landlock_add_rule, const int, ruleset_fd, const enum landlock_rule_type, rule_type, const void __user *const, rule_attr, const __u32, flags) { - struct landlock_path_beneath_attr path_beneath_attr; - struct path path; struct landlock_ruleset *ruleset; - int res, err; - access_mask_t mask; + int err; if (!landlock_initialized) return -EOPNOTSUPP; @@ -324,48 +364,14 @@ SYSCALL_DEFINE4(landlock_add_rule, const int, ruleset_fd, if (IS_ERR(ruleset)) return PTR_ERR(ruleset); - if (rule_type != LANDLOCK_RULE_PATH_BENEATH) { - err = -EINVAL; - goto out_put_ruleset; - } - - /* Copies raw user space buffer, only one type for now. */ - res = copy_from_user(&path_beneath_attr, rule_attr, - sizeof(path_beneath_attr)); - if (res) { - err = -EFAULT; - goto out_put_ruleset; - } - - /* - * Informs about useless rule: empty allowed_access (i.e. deny rules) - * are ignored in path walks. - */ - if (!path_beneath_attr.allowed_access) { - err = -ENOMSG; - goto out_put_ruleset; - } - /* - * Checks that allowed_access matches the @ruleset constraints - * (ruleset->access_masks[0] is automatically upgraded to 64-bits). - */ - mask = landlock_get_raw_fs_access_mask(ruleset, 0); - if ((path_beneath_attr.allowed_access | mask) != mask) { + switch (rule_type) { + case LANDLOCK_RULE_PATH_BENEATH: + err = add_rule_path_beneath(ruleset, rule_attr); + break; + default: err = -EINVAL; - goto out_put_ruleset; + break; } - - /* Gets and checks the new rule. */ - err = get_path_from_fd(path_beneath_attr.parent_fd, &path); - if (err) - goto out_put_ruleset; - - /* Imports the new rule. */ - err = landlock_append_fs_rule(ruleset, &path, - path_beneath_attr.allowed_access); - path_put(&path); - -out_put_ruleset: landlock_put_ruleset(ruleset); return err; }
Change the landlock_add_rule() syscall to support new rule types in future Landlock versions. Add the add_rule_path_beneath() helper to support current filesystem rules. Signed-off-by: Konstantin Meskhidze <konstantin.meskhidze@huawei.com> --- Changes since v8: * Refactors commit message. * Minor fixes. Changes since v7: * None Changes since v6: * None Changes since v5: * Refactors syscall landlock_add_rule() and add_rule_path_beneath() helper to make argument check ordering consistent and get rid of partial revertings in following patches. * Rolls back refactoring base_test.c seltest. * Formats code with clang-format-14. Changes since v4: * Refactors add_rule_path_beneath() and landlock_add_rule() functions to optimize code usage. * Refactors base_test.c seltest: adds LANDLOCK_RULE_PATH_BENEATH rule type in landlock_add_rule() call. Changes since v3: * Split commit. * Refactors landlock_add_rule syscall. --- security/landlock/syscalls.c | 94 +++++++++++++++++++----------------- 1 file changed, 50 insertions(+), 44 deletions(-)