[PATCH v1] audit: free proctitle in context so it can be set by fork
by Richard Guy Briggs
Original title: fixes clean proctitle in audit context on exec call
Between the actual process startup (fork systemd) and the executable file
replacement (exec), systemd sets a temporary file name (executable file
name in parentheses). If an auditable system call occurs at this point,
the audit context will latch the temporary process name into the cache.
This name will not change again. The patch clears proctitle into the
audit cache when the exec call is made, allowing the new process name to
be latched.
Suggested by Roman Dolgikh https://github.com/rmd4ctf 2025-06-11
Link: https://github.com/linux-audit/audit-kernel/issues/170.
Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com>
---
fs/exec.c | 2 ++
include/linux/audit.h | 9 +++++++++
kernel/auditsc.c | 4 ++--
3 files changed, 13 insertions(+), 2 deletions(-)
diff --git a/fs/exec.c b/fs/exec.c
index b92fe7db176c..bd51489dec23 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1744,6 +1744,8 @@ static int exec_binprm(struct linux_binprm *bprm)
fput(exec);
}
+ /* clear proctitle in audit context to allow replacement */
+ audit_proctitle_free(audit_context());
audit_bprm(bprm);
trace_sched_process_exec(current, old_pid, bprm);
ptrace_event(PTRACE_EVENT_EXEC, old_vpid);
diff --git a/include/linux/audit.h b/include/linux/audit.h
index 45abb3722d30..03ae563ca348 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -320,6 +320,7 @@ static inline void audit_cfg_lsm(const struct lsm_id *lsmid, int flags)
/* These are defined in auditsc.c */
/* Public API */
extern int audit_alloc(struct task_struct *task);
+extern void __audit_proctitle_free(struct audit_context *context);
extern void __audit_free(struct task_struct *task);
extern void __audit_uring_entry(u8 op);
extern void __audit_uring_exit(int success, long code);
@@ -353,6 +354,11 @@ static inline bool audit_dummy_context(void)
void *p = audit_context();
return !p || *(int *)p;
}
+static inline void audit_proctitle_free(struct audit_context *context)
+{
+ if (unlikely(!audit_dummy_context()))
+ __audit_proctitle_free(context);
+}
static inline void audit_free(struct task_struct *task)
{
if (unlikely(task->audit_context))
@@ -470,6 +476,7 @@ static inline void audit_bprm(struct linux_binprm *bprm)
if (unlikely(!audit_dummy_context()))
__audit_bprm(bprm);
}
+
static inline int audit_socketcall(int nargs, unsigned long *args)
{
if (unlikely(!audit_dummy_context()))
@@ -605,6 +612,8 @@ static inline int audit_alloc(struct task_struct *task)
{
return 0;
}
+static inline void audit_proctitle_free(struct audit_context *context)
+{ }
static inline void audit_free(struct task_struct *task)
{ }
static inline void audit_uring_entry(u8 op)
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 6610e667c728..69484ab2c8bc 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -913,7 +913,7 @@ void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx)
rcu_read_unlock();
}
-static inline void audit_proctitle_free(struct audit_context *context)
+void __audit_proctitle_free(struct audit_context *context)
{
kfree(context->proctitle.value);
context->proctitle.value = NULL;
@@ -1086,7 +1086,7 @@ 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);
+ __audit_proctitle_free(context);
free_tree_refs(context);
kfree(context->filterkey);
kfree(context);
--
2.43.5
3 days, 15 hours
- 3
- 3
audit-4.2.1 released
by Steve Grubb
Hello,
We just released a new version of the audit package. It can be downloaded
from:
https://github.com/linux-audit/audit-userspace/releases/
The ChangeLog is:
- Truncate overlong comm values instead of rejecting them
- create /run/audit via tmpfiles
- install bash completions under per-command names
- Better validate numeric values when parsing logs and config options
- make GSS handshakes nonblocking
- Fix a couple non-thread safe collisions in libauparse
- allow tls_psk_file to be optional with per-identity keys
This is a "do over" release to fix the rejected events when the comm field is
improperly sized. A couple other cleanups were added. If you are packaging
this note the change to bash completions and adding /run/audit by systemd
temp files.
If you notice any problems with this release, please let us know.
SHA256: 42876d195ee2ded19e5f72d7664096eee314928aa36ad346719ba5b25818fc84
-Steve
PS - Does anyone use audispd-zos-remote? I'm considering dropping it as it
hasn't been meaningfully updated in almost 20 years and needs some work.
1 week, 4 days
- 1
- 0
audit-4.2 released
by Steve Grubb
Hello,
We just released a new version of the audit package. It can be downloaded
from:
https://github.com/linux-audit/audit-userspace/releases/
The ChangeLog is:
- Put the bash completions in /usr/share/bash-completion/completions/
- Add KillMode=mixed to the auditd unit file (Issue 272)
- Update perm table to add recent syscalls to it
- Auditd - prevent netlink congestion
- Propogate feed consumption errors into auparse_feed and auparse_flush_feed
- Add TLS support for remote logging (Sergio Correia)
- Add IPv6 support to IDS plugin
- Many code cleanups
First, if you are packaging this, note that the bash completions moved to a
more correct location. Second, if you are a distribution, you probably want
to backport commit abea35d2 "prevent netlink congestion" to all stable or
long term releases. It prevents the kernel from entering into state that is
hard to recover from when the backlog fills.
The big feature of this release is TLS protected remote logging. Thanks to
Sergio Correia for this. It's designed to work with pre-shared keys and
supports PQC ciphers. It does not support certificates.
Otherwise, this was a big bug fix release with around 170 total commits and
probably 100 of those fixing things found by static analysis and code review.
If you notice any problems with this release, please let us know.
SHA256: 5c275e80dd96c1e55dc0f850f63568a73b678acc502963a7926cfdb5ea505eae
-Steve
2 weeks, 2 days
- 1
- 1
-w deprecation and -F dir= equivalence
by seth＠soulintheshell.com
Hello,
I read in the auditctl manual that -w $path is deprecated and should be
replaced by -F path=$path or -F dir=$path.
However it seems to me that their behavior is not the same, notably I
see auditd (4.0.2) fails to load its rules it $path does not
exists. $path may be created later in the system initialization or only
after a precise event (eg: /var/run/faillock in a tmpfs and only
created at first login).
So should I conclude that -w should still be used for paths that may not
exists at initialization ? Am I missing something ?
Is there a timeline for -w deprecation ?
Thanks,
-Seth
2 weeks, 3 days
- 2
- 3
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