[PATCH 4/4][v2] audit: call audit_bprm() only once to add AUDIT_EXECVE information

Move the audit_bprm() call from search_binary_handler() to exec_binprm(). This allows us to get rid of the mm member of struct audit_aux_data_execve since bprm->mm will equal current->mm. This also mitigates the issue that ->argc could be modified by the load_binary() call in search_binary_handler(). audit_bprm() was being called to add an AUDIT_EXECVE record to the audit context every time search_binary_handler() was recursively called. Only one reference is necessary. Reported-by: Oleg Nesterov <onestero(a)redhat.com&gt; Cc: Eric Paris <eparis(a)redhat.com&gt; Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com&gt; --- fs/exec.c | 5 +---- include/linux/audit.h | 9 +++------ kernel/audit.h | 1 - kernel/auditsc.c | 4 ---- 4 files changed, 4 insertions(+), 15 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index 8875dd1..47d7edb 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1385,10 +1385,6 @@ int search_binary_handler(struct linux_binprm *bprm) if (retval) return retval; - retval = audit_bprm(bprm); - if (retval) - return retval; - retval = -ENOENT; retry: read_lock(&binfmt_lock); @@ -1436,6 +1432,7 @@ static int exec_binprm(struct linux_binprm *bprm) ret = search_binary_handler(bprm); if (ret >= 0) { + audit_bprm(bprm); trace_sched_process_exec(current, old_pid, bprm); ptrace_event(PTRACE_EVENT_EXEC, old_vpid); current->did_exec = 1; diff --git a/include/linux/audit.h b/include/linux/audit.h index fffefbd..a757e6c 100644 --- a/include/linux/audit.h +++ b/include/linux/audit.h @@ -236,11 +236,10 @@ static inline void audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid if (unlikely(!audit_dummy_context())) __audit_ipc_set_perm(qbytes, uid, gid, mode); } -static inline int audit_bprm(struct linux_binprm *bprm) +static inline void audit_bprm(struct linux_binprm *bprm) { if (unlikely(!audit_dummy_context())) __audit_bprm(bprm); - return 0; } static inline int audit_socketcall(int nargs, unsigned long *args) { @@ -367,10 +366,8 @@ static inline void audit_ipc_obj(struct kern_ipc_perm *ipcp) static inline void audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode) { } -static inline int audit_bprm(struct linux_binprm *bprm) -{ - return 0; -} +static inline void audit_bprm(struct linux_binprm *bprm) +{ } static inline int audit_socketcall(int nargs, unsigned long *args) { return 0; diff --git a/kernel/audit.h b/kernel/audit.h index e7b94ab..b779642 100644 --- a/kernel/audit.h +++ b/kernel/audit.h @@ -199,7 +199,6 @@ struct audit_context { } mmap; struct { int argc; - struct mm_struct *mm; } execve; }; int fds[2]; diff --git a/kernel/auditsc.c b/kernel/auditsc.c index eabe76a..dc1adee 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -1145,9 +1145,6 @@ static void audit_log_execve_info(struct audit_context *context, const char __user *p; char *buf; - if (context->execve.mm != current->mm) - return; /* execve failed, no additional info */ - p = (const char __user *)current->mm->arg_start; audit_log_format(*ab, "argc=%d", context->execve.argc); @@ -2118,7 +2115,6 @@ void __audit_bprm(struct linux_binprm *bprm) context->type = AUDIT_EXECVE; context->execve.argc = bprm->argc; - context->execve.mm = bprm->mm; } -- 1.7.1