From: Casey Schaufler Date: Thu, 10 Nov 2011 23:02:22 +0000 (-0800) Subject: Smack: smackfs cipso seq read repair X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=40809565ca57a8e94bae20b22da014c44ec233f6;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git Smack: smackfs cipso seq read repair Commit 272cd7a8c67dd40a31ecff76a503bbb84707f757 introduced a change to the way rule lists are handled and reported in the smackfs filesystem. One of the issues addressed had to do with the termination of read requests on /smack/load. This change introduced a error in /smack/cipso, which shares some of the same list processing code. This patch updates all the file access list handling in smackfs to use the code introduced for /smack/load. Signed-off-by: Casey Schaufler --- diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c index 6aceef518a41..5c32f36ff706 100644 --- a/security/smack/smackfs.c +++ b/security/smack/smackfs.c @@ -102,9 +102,6 @@ static int smk_cipso_doi_value = SMACK_CIPSO_DOI_DEFAULT; const char *smack_cipso_option = SMACK_CIPSO_OPTION; - -#define SEQ_READ_FINISHED ((loff_t)-1) - /* * Values for parsing cipso rules * SMK_DIGITLEN: Length of a digit field in a rule. @@ -357,10 +354,12 @@ static ssize_t smk_write_load_list(struct file *file, const char __user *buf, rc = count; /* + * If this is "load" as opposed to "load-self" and a new rule + * it needs to get added for reporting. * smk_set_access returns true if there was already a rule * for the subject/object pair, and false if it was new. */ - if (!smk_set_access(rule, rule_list, rule_lock)) { + if (load && !smk_set_access(rule, rule_list, rule_lock)) { smlp = kzalloc(sizeof(*smlp), GFP_KERNEL); if (smlp != NULL) { smlp->smk_rule = rule; @@ -377,12 +376,12 @@ out: return rc; } - /* - * Seq_file read operations for /smack/load + * Core logic for smackfs seq list operations. */ -static void *load_seq_start(struct seq_file *s, loff_t *pos) +static void *smk_seq_start(struct seq_file *s, loff_t *pos, + struct list_head *head) { struct list_head *list; @@ -390,7 +389,7 @@ static void *load_seq_start(struct seq_file *s, loff_t *pos) * This is 0 the first time through. */ if (s->index == 0) - s->private = &smack_rule_list; + s->private = head; if (s->private == NULL) return NULL; @@ -404,11 +403,12 @@ static void *load_seq_start(struct seq_file *s, loff_t *pos) return list; } -static void *load_seq_next(struct seq_file *s, void *v, loff_t *pos) +static void *smk_seq_next(struct seq_file *s, void *v, loff_t *pos, + struct list_head *head) { struct list_head *list = v; - if (list_is_last(list, &smack_rule_list)) { + if (list_is_last(list, head)) { s->private = NULL; return NULL; } @@ -416,6 +416,25 @@ static void *load_seq_next(struct seq_file *s, void *v, loff_t *pos) return list->next; } +static void smk_seq_stop(struct seq_file *s, void *v) +{ + /* No-op */ +} + +/* + * Seq_file read operations for /smack/load + */ + +static void *load_seq_start(struct seq_file *s, loff_t *pos) +{ + return smk_seq_start(s, pos, &smack_rule_list); +} + +static void *load_seq_next(struct seq_file *s, void *v, loff_t *pos) +{ + return smk_seq_next(s, v, pos, &smack_rule_list); +} + static int load_seq_show(struct seq_file *s, void *v) { struct list_head *list = v; @@ -446,16 +465,11 @@ static int load_seq_show(struct seq_file *s, void *v) return 0; } -static void load_seq_stop(struct seq_file *s, void *v) -{ - /* No-op */ -} - static const struct seq_operations load_seq_ops = { .start = load_seq_start, .next = load_seq_next, .show = load_seq_show, - .stop = load_seq_stop, + .stop = smk_seq_stop, }; /** @@ -574,28 +588,12 @@ static void smk_unlbl_ambient(char *oldambient) static void *cipso_seq_start(struct seq_file *s, loff_t *pos) { - if (*pos == SEQ_READ_FINISHED) - return NULL; - if (list_empty(&smack_known_list)) - return NULL; - - return smack_known_list.next; + return smk_seq_start(s, pos, &smack_known_list); } static void *cipso_seq_next(struct seq_file *s, void *v, loff_t *pos) { - struct list_head *list = v; - - /* - * labels with no associated cipso value wont be printed - * in cipso_seq_show - */ - if (list_is_last(list, &smack_known_list)) { - *pos = SEQ_READ_FINISHED; - return NULL; - } - - return list->next; + return smk_seq_next(s, v, pos, &smack_known_list); } /* @@ -634,16 +632,11 @@ static int cipso_seq_show(struct seq_file *s, void *v) return 0; } -static void cipso_seq_stop(struct seq_file *s, void *v) -{ - /* No-op */ -} - static const struct seq_operations cipso_seq_ops = { .start = cipso_seq_start, - .stop = cipso_seq_stop, .next = cipso_seq_next, .show = cipso_seq_show, + .stop = smk_seq_stop, }; /** @@ -788,23 +781,12 @@ static const struct file_operations smk_cipso_ops = { static void *netlbladdr_seq_start(struct seq_file *s, loff_t *pos) { - if (*pos == SEQ_READ_FINISHED) - return NULL; - if (list_empty(&smk_netlbladdr_list)) - return NULL; - return smk_netlbladdr_list.next; + return smk_seq_start(s, pos, &smk_netlbladdr_list); } static void *netlbladdr_seq_next(struct seq_file *s, void *v, loff_t *pos) { - struct list_head *list = v; - - if (list_is_last(list, &smk_netlbladdr_list)) { - *pos = SEQ_READ_FINISHED; - return NULL; - } - - return list->next; + return smk_seq_next(s, v, pos, &smk_netlbladdr_list); } #define BEBITS (sizeof(__be32) * 8) @@ -828,16 +810,11 @@ static int netlbladdr_seq_show(struct seq_file *s, void *v) return 0; } -static void netlbladdr_seq_stop(struct seq_file *s, void *v) -{ - /* No-op */ -} - static const struct seq_operations netlbladdr_seq_ops = { .start = netlbladdr_seq_start, - .stop = netlbladdr_seq_stop, .next = netlbladdr_seq_next, .show = netlbladdr_seq_show, + .stop = smk_seq_stop, }; /** @@ -1405,23 +1382,14 @@ static void *load_self_seq_start(struct seq_file *s, loff_t *pos) { struct task_smack *tsp = current_security(); - if (*pos == SEQ_READ_FINISHED) - return NULL; - if (list_empty(&tsp->smk_rules)) - return NULL; - return tsp->smk_rules.next; + return smk_seq_start(s, pos, &tsp->smk_rules); } static void *load_self_seq_next(struct seq_file *s, void *v, loff_t *pos) { struct task_smack *tsp = current_security(); - struct list_head *list = v; - if (list_is_last(list, &tsp->smk_rules)) { - *pos = SEQ_READ_FINISHED; - return NULL; - } - return list->next; + return smk_seq_next(s, v, pos, &tsp->smk_rules); } static int load_self_seq_show(struct seq_file *s, void *v) @@ -1453,16 +1421,11 @@ static int load_self_seq_show(struct seq_file *s, void *v) return 0; } -static void load_self_seq_stop(struct seq_file *s, void *v) -{ - /* No-op */ -} - static const struct seq_operations load_self_seq_ops = { .start = load_self_seq_start, .next = load_self_seq_next, .show = load_self_seq_show, - .stop = load_self_seq_stop, + .stop = smk_seq_stop, };