[PATCH ghak138] audit: move audit_return_fixup before the filters

From: Richard Guy Briggs
Date: Wed Aug 24 2022 - 23:10:19 EST


The success and return_code are needed by the filters. Move
audit_return_fixup() before the filters.

The pid member of struct audit_context is never used. Remove it.

The audit_reset_context() comment about unconditionally resetting
"ctx->state" should read "ctx->context".

The proctitle is intentionally stored between syscalls. Only free it in
audit_free_context().

Be explicit in checking the struct audit_context "context" member enum
value rather than assuming the order of context enum values.

Cc: stable@xxxxxxxxxxxxxxx
Fixes: 12c5e81d3fd0 ("audit: prepare audit_context for use in calling contexts beyond syscalls")
Signed-off-by: Richard Guy Briggs <rgb@xxxxxxxxxx>
---
kernel/audit.h | 2 +-
kernel/auditsc.c | 12 ++++++------
2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/kernel/audit.h b/kernel/audit.h
index 58b66543b4d5..d6eb7b59c791 100644
--- a/kernel/audit.h
+++ b/kernel/audit.h
@@ -133,7 +133,7 @@ struct audit_context {
struct sockaddr_storage *sockaddr;
size_t sockaddr_len;
/* Save things to print about task_struct */
- pid_t pid, ppid;
+ pid_t ppid;
kuid_t uid, euid, suid, fsuid;
kgid_t gid, egid, sgid, fsgid;
unsigned long personality;
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 9226746dcf0a..9f8c05228d6d 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -965,7 +965,7 @@ static void audit_reset_context(struct audit_context *ctx)
if (!ctx)
return;

- /* if ctx is non-null, reset the "ctx->state" regardless */
+ /* if ctx is non-null, reset the "ctx->context" regardless */
ctx->context = AUDIT_CTX_UNUSED;
if (ctx->dummy)
return;
@@ -1002,7 +1002,7 @@ static void audit_reset_context(struct audit_context *ctx)
kfree(ctx->sockaddr);
ctx->sockaddr = NULL;
ctx->sockaddr_len = 0;
- ctx->pid = ctx->ppid = 0;
+ ctx->ppid = 0;
ctx->uid = ctx->euid = ctx->suid = ctx->fsuid = KUIDT_INIT(0);
ctx->gid = ctx->egid = ctx->sgid = ctx->fsgid = KGIDT_INIT(0);
ctx->personality = 0;
@@ -1016,7 +1016,6 @@ static void audit_reset_context(struct audit_context *ctx)
WARN_ON(!list_empty(&ctx->killed_trees));
audit_free_module(ctx);
ctx->fds[0] = -1;
- audit_proctitle_free(ctx);
ctx->type = 0; /* reset last for audit_free_*() */
}

@@ -1077,6 +1076,7 @@ static inline void audit_free_context(struct audit_context *context)
{
/* resetting is extra work, but it is likely just noise */
audit_reset_context(context);
+ audit_proctitle_free(context);
free_tree_refs(context);
kfree(context->filterkey);
kfree(context);
@@ -1940,6 +1940,7 @@ void __audit_uring_exit(int success, long code)
goto out;
}

+ audit_return_fixup(ctx, success, code);
if (ctx->context == AUDIT_CTX_SYSCALL) {
/*
* NOTE: See the note in __audit_uring_entry() about the case
@@ -1981,7 +1982,6 @@ void __audit_uring_exit(int success, long code)
audit_filter_inodes(current, ctx);
if (ctx->current_state != AUDIT_STATE_RECORD)
goto out;
- audit_return_fixup(ctx, success, code);
audit_log_exit();

out:
@@ -2065,13 +2065,13 @@ void __audit_syscall_exit(int success, long return_code)
if (!list_empty(&context->killed_trees))
audit_kill_trees(context);

+ audit_return_fixup(context, success, return_code);
/* run through both filters to ensure we set the filterkey properly */
audit_filter_syscall(current, context);
audit_filter_inodes(current, context);
- if (context->current_state < AUDIT_STATE_RECORD)
+ if (context->current_state != AUDIT_STATE_RECORD)
goto out;

- audit_return_fixup(context, success, return_code);
audit_log_exit();

out:
--
2.27.0