From d7481b24b816b8c3955a9eaf01b97e2bd7f61a37 Mon Sep 17 00:00:00 2001 From: Richard Guy Briggs Date: Fri, 3 Jul 2020 12:56:19 -0400 Subject: [PATCH] audit: issue CWD record to accompany LSM_AUDIT_DATA_* records The LSM_AUDIT_DATA_* records for PATH, FILE, IOCTL_OP, DENTRY and INODE are incomplete without the task context of the AUDIT Current Working Directory record. Add it. This record addition can't use audit_dummy_context to determine whether or not to store the record information since the LSM_AUDIT_DATA_* records are initiated by various LSMs independent of any audit rules. context->in_syscall is used to determine if it was called in user context like audit_getname. Please see the upstream issue https://github.com/linux-audit/audit-kernel/issues/96 Adapted from Vladis Dronov's v2 patch. Signed-off-by: Richard Guy Briggs Signed-off-by: Paul Moore --- include/linux/audit.h | 9 ++++++++- kernel/auditsc.c | 17 +++++++++++++++-- security/lsm_audit.c | 5 +++++ 3 files changed, 28 insertions(+), 3 deletions(-) diff --git a/include/linux/audit.h b/include/linux/audit.h index b5478c64bc69..523f77494847 100644 --- a/include/linux/audit.h +++ b/include/linux/audit.h @@ -292,7 +292,7 @@ extern void __audit_syscall_entry(int major, unsigned long a0, unsigned long a1, extern void __audit_syscall_exit(int ret_success, long ret_value); extern struct filename *__audit_reusename(const __user char *uptr); extern void __audit_getname(struct filename *name); - +extern void __audit_getcwd(void); extern void __audit_inode(struct filename *name, const struct dentry *dentry, unsigned int flags); extern void __audit_file(const struct file *); @@ -351,6 +351,11 @@ static inline void audit_getname(struct filename *name) if (unlikely(!audit_dummy_context())) __audit_getname(name); } +static inline void audit_getcwd(void) +{ + if (unlikely(audit_context())) + __audit_getcwd(); +} static inline void audit_inode(struct filename *name, const struct dentry *dentry, unsigned int aflags) { @@ -579,6 +584,8 @@ static inline struct filename *audit_reusename(const __user char *name) } static inline void audit_getname(struct filename *name) { } +static inline void audit_getcwd(void) +{ } static inline void audit_inode(struct filename *name, const struct dentry *dentry, unsigned int aflags) diff --git a/kernel/auditsc.c b/kernel/auditsc.c index eae1a599ffe3..6884b50069d1 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -1891,6 +1891,20 @@ __audit_reusename(const __user char *uptr) return NULL; } +inline void _audit_getcwd(struct audit_context *context) +{ + if (!context->pwd.dentry) + get_fs_pwd(current->fs, &context->pwd); +} + +void __audit_getcwd(void) +{ + struct audit_context *context = audit_context(); + + if (context->in_syscall) + _audit_getcwd(context); +} + /** * __audit_getname - add a name to the list * @name: name to add @@ -1915,8 +1929,7 @@ void __audit_getname(struct filename *name) name->aname = n; name->refcnt++; - if (!context->pwd.dentry) - get_fs_pwd(current->fs, &context->pwd); + _audit_getcwd(context); } static inline int audit_copy_fcaps(struct audit_names *name, diff --git a/security/lsm_audit.c b/security/lsm_audit.c index 2d2bf49016f4..7c555621c2bd 100644 --- a/security/lsm_audit.c +++ b/security/lsm_audit.c @@ -241,6 +241,7 @@ static void dump_common_audit_data(struct audit_buffer *ab, audit_log_untrustedstring(ab, inode->i_sb->s_id); audit_log_format(ab, " ino=%lu", inode->i_ino); } + audit_getcwd(); break; } case LSM_AUDIT_DATA_FILE: { @@ -254,6 +255,7 @@ static void dump_common_audit_data(struct audit_buffer *ab, audit_log_untrustedstring(ab, inode->i_sb->s_id); audit_log_format(ab, " ino=%lu", inode->i_ino); } + audit_getcwd(); break; } case LSM_AUDIT_DATA_IOCTL_OP: { @@ -269,6 +271,7 @@ static void dump_common_audit_data(struct audit_buffer *ab, } audit_log_format(ab, " ioctlcmd=0x%hx", a->u.op->cmd); + audit_getcwd(); break; } case LSM_AUDIT_DATA_DENTRY: { @@ -283,6 +286,7 @@ static void dump_common_audit_data(struct audit_buffer *ab, audit_log_untrustedstring(ab, inode->i_sb->s_id); audit_log_format(ab, " ino=%lu", inode->i_ino); } + audit_getcwd(); break; } case LSM_AUDIT_DATA_INODE: { @@ -300,6 +304,7 @@ static void dump_common_audit_data(struct audit_buffer *ab, audit_log_format(ab, " dev="); audit_log_untrustedstring(ab, inode->i_sb->s_id); audit_log_format(ab, " ino=%lu", inode->i_ino); + audit_getcwd(); break; } case LSM_AUDIT_DATA_TASK: {