This patch passes the full response so that the audit function can use all of it. The audit function was updated to log the additional information in the AUDIT_FANOTIFY record. Currently the only type of fanotify info that is defined is an audit rule number, but convert it to hex encoding to future-proof the field. Hex encoding suggested by Paul Moore <paul@xxxxxxxxxxxxxx>. Sample records: type=FANOTIFY msg=audit(1600385147.372:590): resp=2 fan_type=1 fan_info=3137 subj_trust=3 obj_trust=5 type=FANOTIFY msg=audit(1659730979.839:284): resp=1 fan_type=0 fan_info=3F subj_trust=2 obj_trust=2 Suggested-by: Steve Grubb <sgrubb@xxxxxxxxxx> Link: https://lore.kernel.org/r/3075502.aeNJFYEL58@x2 Signed-off-by: Richard Guy Briggs <rgb@xxxxxxxxxx> --- fs/notify/fanotify/fanotify.c | 3 ++- include/linux/audit.h | 9 +++++---- kernel/auditsc.c | 25 ++++++++++++++++++++++--- 3 files changed, 29 insertions(+), 8 deletions(-) diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index 24ec1d66d5a8..29bdd99b29fa 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -273,7 +273,8 @@ static int fanotify_get_response(struct fsnotify_group *group, /* Check if the response should be audited */ if (event->response & FAN_AUDIT) - audit_fanotify(event->response & ~FAN_AUDIT); + audit_fanotify(event->response & ~FAN_AUDIT, + &event->audit_rule); pr_debug("%s: group=%p event=%p about to return ret=%d\n", __func__, group, event, ret); diff --git a/include/linux/audit.h b/include/linux/audit.h index d6b7d0c7ce43..31086a72e32a 100644 --- a/include/linux/audit.h +++ b/include/linux/audit.h @@ -14,6 +14,7 @@ #include <linux/audit_arch.h> #include <uapi/linux/audit.h> #include <uapi/linux/netfilter/nf_tables.h> +#include <uapi/linux/fanotify.h> #define AUDIT_INO_UNSET ((unsigned long)-1) #define AUDIT_DEV_UNSET ((dev_t)-1) @@ -416,7 +417,7 @@ extern void __audit_log_capset(const struct cred *new, const struct cred *old); extern void __audit_mmap_fd(int fd, int flags); extern void __audit_openat2_how(struct open_how *how); extern void __audit_log_kern_module(char *name); -extern void __audit_fanotify(u32 response); +extern void __audit_fanotify(u32 response, struct fanotify_response_info_audit_rule *friar); extern void __audit_tk_injoffset(struct timespec64 offset); extern void __audit_ntp_log(const struct audit_ntp_data *ad); extern void __audit_log_nfcfg(const char *name, u8 af, unsigned int nentries, @@ -523,10 +524,10 @@ static inline void audit_log_kern_module(char *name) __audit_log_kern_module(name); } -static inline void audit_fanotify(u32 response) +static inline void audit_fanotify(u32 response, struct fanotify_response_info_audit_rule *friar) { if (!audit_dummy_context()) - __audit_fanotify(response); + __audit_fanotify(response, friar); } static inline void audit_tk_injoffset(struct timespec64 offset) @@ -679,7 +680,7 @@ static inline void audit_log_kern_module(char *name) { } -static inline void audit_fanotify(u32 response) +static inline void audit_fanotify(u32 response, struct fanotify_response_info_audit_rule *friar) { } static inline void audit_tk_injoffset(struct timespec64 offset) diff --git a/kernel/auditsc.c b/kernel/auditsc.c index d1fb821de104..8d523066d81f 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -64,6 +64,7 @@ #include <uapi/linux/limits.h> #include <uapi/linux/netfilter/nf_tables.h> #include <uapi/linux/openat2.h> // struct open_how +#include <uapi/linux/fanotify.h> #include "audit.h" @@ -2877,10 +2878,28 @@ void __audit_log_kern_module(char *name) context->type = AUDIT_KERN_MODULE; } -void __audit_fanotify(u32 response) +void __audit_fanotify(u32 response, struct fanotify_response_info_audit_rule *friar) { - audit_log(audit_context(), GFP_KERNEL, - AUDIT_FANOTIFY, "resp=%u", response); + struct audit_context *ctx = audit_context(); + struct audit_buffer *ab; + char numbuf[12]; + + if (friar->hdr.type == FAN_RESPONSE_INFO_NONE) { + audit_log(audit_context(), GFP_KERNEL, AUDIT_FANOTIFY, + "resp=%u fan_type=%u fan_info=3F subj_trust=2 obj_trust=2", + response, FAN_RESPONSE_INFO_NONE); + return; + } + ab = audit_log_start(ctx, GFP_KERNEL, AUDIT_FANOTIFY); + if (ab) { + audit_log_format(ab, "resp=%u fan_type=%u fan_info=", + response, friar->hdr.type); + snprintf(numbuf, sizeof(numbuf), "%u", friar->rule_number); + audit_log_n_hex(ab, numbuf, sizeof(numbuf)); + audit_log_format(ab, " subj_trust=%u obj_trust=%u", + friar->subj_trust, friar->obj_trust); + audit_log_end(ab); + } } void __audit_tk_injoffset(struct timespec64 offset) -- 2.27.0
