diff options
| -rw-r--r-- | include/linux/security.h | 9 | ||||
| -rw-r--r-- | security/apparmor/lsm.c | 15 | ||||
| -rw-r--r-- | security/security.c | 55 | ||||
| -rw-r--r-- | security/selinux/hooks.c | 44 | ||||
| -rw-r--r-- | security/smack/smack_lsm.c | 23 |
5 files changed, 68 insertions, 78 deletions
diff --git a/include/linux/security.h b/include/linux/security.h index 334f75aa7289..750130a7b9dd 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -492,8 +492,8 @@ int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen); int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen); int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen); int security_locked_down(enum lockdown_reason what); -int lsm_fill_user_ctx(struct lsm_ctx __user *ctx, void *context, - size_t context_size, u64 id, u64 flags); +int lsm_fill_user_ctx(struct lsm_ctx __user *uctx, size_t *uctx_len, + void *val, size_t val_len, u64 id, u64 flags); #else /* CONFIG_SECURITY */ static inline int call_blocking_lsm_notifier(enum lsm_event event, void *data) @@ -1424,8 +1424,9 @@ static inline int security_locked_down(enum lockdown_reason what) { return 0; } -static inline int lsm_fill_user_ctx(struct lsm_ctx __user *ctx, void *context, - size_t context_size, u64 id, u64 flags) +static inline int lsm_fill_user_ctx(struct lsm_ctx __user *uctx, + size_t *uctx_len, void *val, size_t val_len, + u64 id, u64 flags) { return -EOPNOTSUPP; } diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c index 8165f80c10ff..332198e0a017 100644 --- a/security/apparmor/lsm.c +++ b/security/apparmor/lsm.c @@ -782,7 +782,6 @@ static int apparmor_getselfattr(unsigned int attr, struct lsm_ctx __user *lx, int error = -ENOENT; struct aa_task_ctx *ctx = task_ctx(current); struct aa_label *label = NULL; - size_t total_len = 0; char *value; switch (attr) { @@ -804,22 +803,14 @@ static int apparmor_getselfattr(unsigned int attr, struct lsm_ctx __user *lx, if (label) { error = aa_getprocattr(label, &value, false); - if (error > 0) { - total_len = ALIGN(struct_size(lx, ctx, error), 8); - if (total_len > *size) - error = -E2BIG; - else if (lx) - error = lsm_fill_user_ctx(lx, value, error, - LSM_ID_APPARMOR, 0); - else - error = 1; - } + if (error > 0) + error = lsm_fill_user_ctx(lx, size, value, error, + LSM_ID_APPARMOR, 0); kfree(value); } aa_put_label(label); - *size = total_len; if (error < 0) return error; return 1; diff --git a/security/security.c b/security/security.c index 78e7ffcc9f6c..86f7a1995991 100644 --- a/security/security.c +++ b/security/security.c @@ -772,42 +772,49 @@ static int lsm_superblock_alloc(struct super_block *sb) /** * lsm_fill_user_ctx - Fill a user space lsm_ctx structure - * @ctx: an LSM context to be filled - * @context: the new context value - * @context_size: the size of the new context value + * @uctx: a userspace LSM context to be filled + * @uctx_len: available uctx size (input), used uctx size (output) + * @val: the new LSM context value + * @val_len: the size of the new LSM context value * @id: LSM id * @flags: LSM defined flags * - * Fill all of the fields in a user space lsm_ctx structure. - * Caller is assumed to have verified that @ctx has enough space - * for @context. + * Fill all of the fields in a userspace lsm_ctx structure. * - * Returns 0 on success, -EFAULT on a copyout error, -ENOMEM - * if memory can't be allocated. + * Returns 0 on success, -E2BIG if userspace buffer is not large enough, + * -EFAULT on a copyout error, -ENOMEM if memory can't be allocated. */ -int lsm_fill_user_ctx(struct lsm_ctx __user *ctx, void *context, - size_t context_size, u64 id, u64 flags) +int lsm_fill_user_ctx(struct lsm_ctx __user *uctx, size_t *uctx_len, + void *val, size_t val_len, + u64 id, u64 flags) { - struct lsm_ctx *lctx; - size_t locallen = struct_size(lctx, ctx, context_size); + struct lsm_ctx *nctx = NULL; + size_t nctx_len; int rc = 0; - lctx = kzalloc(locallen, GFP_KERNEL); - if (lctx == NULL) - return -ENOMEM; - - lctx->id = id; - lctx->flags = flags; - lctx->ctx_len = context_size; - lctx->len = locallen; + nctx_len = ALIGN(struct_size(nctx, ctx, val_len), BITS_PER_LONG / 8); + if (nctx_len > *uctx_len) { + rc = -E2BIG; + goto out; + } - memcpy(lctx->ctx, context, context_size); + nctx = kzalloc(nctx_len, GFP_KERNEL); + if (nctx == NULL) { + rc = -ENOMEM; + goto out; + } + nctx->id = id; + nctx->flags = flags; + nctx->len = nctx_len; + nctx->ctx_len = val_len; + memcpy(nctx->ctx, val, val_len); - if (copy_to_user(ctx, lctx, locallen)) + if (copy_to_user(uctx, nctx, nctx_len)) rc = -EFAULT; - kfree(lctx); - +out: + kfree(nctx); + *uctx_len = nctx_len; return rc; } diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index b6c7930a3ab2..942f2b8c4ebb 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -6486,30 +6486,32 @@ abort_change: return error; } +/** + * selinux_getselfattr - Get SELinux current task attributes + * @attr: the requested attribute + * @ctx: buffer to receive the result + * @size: buffer size (input), buffer size used (output) + * @flags: unused + * + * Fill the passed user space @ctx with the details of the requested + * attribute. + * + * Returns the number of attributes on success, an error code otherwise. + * There will only ever be one attribute. + */ static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx, size_t *size, u32 flags) { - char *value; - size_t total_len; - int len; - int rc = 0; - - len = selinux_lsm_getattr(attr, current, &value); - if (len < 0) - return len; - - total_len = ALIGN(struct_size(ctx, ctx, len), 8); - - if (total_len > *size) - rc = -E2BIG; - else if (ctx) - rc = lsm_fill_user_ctx(ctx, value, len, LSM_ID_SELINUX, 0); - - kfree(value); - *size = total_len; - if (rc < 0) - return rc; - return 1; + int rc; + char *val; + int val_len; + + val_len = selinux_lsm_getattr(attr, current, &val); + if (val_len < 0) + return val_len; + rc = lsm_fill_user_ctx(ctx, size, val, val_len, LSM_ID_SELINUX, 0); + kfree(val); + return (!rc ? 1 : rc); } static int selinux_setselfattr(unsigned int attr, struct lsm_ctx *ctx, diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 12160d060cc1..99664c8cf867 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -3642,28 +3642,17 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode) static int smack_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx, size_t *size, u32 flags) { - struct smack_known *skp = smk_of_current(); - int total; - int slen; int rc; + struct smack_known *skp; if (attr != LSM_ATTR_CURRENT) return -EOPNOTSUPP; - slen = strlen(skp->smk_known) + 1; - total = ALIGN(slen + sizeof(*ctx), 8); - if (total > *size) - rc = -E2BIG; - else if (ctx) - rc = lsm_fill_user_ctx(ctx, skp->smk_known, slen, LSM_ID_SMACK, - 0); - else - rc = 1; - - *size = total; - if (rc >= 0) - return 1; - return rc; + skp = smk_of_current(); + rc = lsm_fill_user_ctx(ctx, size, + skp->smk_known, strlen(skp->smk_known) + 1, + LSM_ID_SMACK, 0); + return (!rc ? 1 : rc); } /** |