From 041d7b98ffe59c59fdd639931dea7d74f9aa9a59 Mon Sep 17 00:00:00 2001 From: Richard Guy Briggs Date: Tue, 23 Dec 2014 13:02:04 -0500 Subject: [PATCH] audit: restore AUDIT_LOGINUID unset ABI A regression was caused by commit 780a7654cee8: audit: Make testing for a valid loginuid explicit. (which in turn attempted to fix a regression caused by e1760bd) When audit_krule_to_data() fills in the rules to get a listing, there was a missing clause to convert back from AUDIT_LOGINUID_SET to AUDIT_LOGINUID. This broke userspace by not returning the same information that was sent and expected. The rule: auditctl -a exit,never -F auid=-1 gives: auditctl -l LIST_RULES: exit,never f24=0 syscall=all when it should give: LIST_RULES: exit,never auid=-1 (0xffffffff) syscall=all Tag it so that it is reported the same way it was set. Create a new private flags audit_krule field (pflags) to store it that won't interact with the public one from the API. Cc: stable@vger.kernel.org # v3.10-rc1+ Signed-off-by: Richard Guy Briggs Signed-off-by: Paul Moore --- include/linux/audit.h | 4 ++++ kernel/auditfilter.c | 10 ++++++++++ 2 files changed, 14 insertions(+) diff --git a/include/linux/audit.h b/include/linux/audit.h index 36dffeccebdb..93331929d643 100644 --- a/include/linux/audit.h +++ b/include/linux/audit.h @@ -47,6 +47,7 @@ struct sk_buff; struct audit_krule { int vers_ops; + u32 pflags; u32 flags; u32 listnr; u32 action; @@ -64,6 +65,9 @@ struct audit_krule { u64 prio; }; +/* Flag to indicate legacy AUDIT_LOGINUID unset usage */ +#define AUDIT_LOGINUID_LEGACY 0x1 + struct audit_field { u32 type; union { diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index c0d148bd7a5c..103586e239a2 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -442,6 +442,7 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data, if ((f->type == AUDIT_LOGINUID) && (f->val == AUDIT_UID_UNSET)) { f->type = AUDIT_LOGINUID_SET; f->val = 0; + entry->rule.pflags |= AUDIT_LOGINUID_LEGACY; } err = audit_field_valid(entry, f); @@ -617,6 +618,13 @@ static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule) data->buflen += data->values[i] = audit_pack_string(&bufp, krule->filterkey); break; + case AUDIT_LOGINUID_SET: + if (krule->pflags & AUDIT_LOGINUID_LEGACY && !f->val) { + data->fields[i] = AUDIT_LOGINUID; + data->values[i] = AUDIT_UID_UNSET; + break; + } + /* fallthrough if set */ default: data->values[i] = f->val; } @@ -633,6 +641,7 @@ static int audit_compare_rule(struct audit_krule *a, struct audit_krule *b) int i; if (a->flags != b->flags || + a->pflags != b->pflags || a->listnr != b->listnr || a->action != b->action || a->field_count != b->field_count) @@ -751,6 +760,7 @@ struct audit_entry *audit_dupe_rule(struct audit_krule *old) new = &entry->rule; new->vers_ops = old->vers_ops; new->flags = old->flags; + new->pflags = old->pflags; new->listnr = old->listnr; new->action = old->action; for (i = 0; i < AUDIT_BITMASK_SIZE; i++) -- 2.20.1