diff options
| author | Masami Hiramatsu (Google) <mhiramat@kernel.org> | 2026-04-20 23:00:48 +0900 |
|---|---|---|
| committer | Masami Hiramatsu (Google) <mhiramat@kernel.org> | 2026-04-21 23:59:29 +0900 |
| commit | 6ad51ada17ed80c9a5f205b4c01c424cac8b0d46 (patch) | |
| tree | e439a6f89037725c2c98cc56c45401d426bbd86d /kernel/trace/fprobe.c | |
| parent | b4e07588e743c989499ca24d49e752c074924a9a (diff) | |
tracing/fprobe: Reject registration of a registered fprobe before init
Reject registration of a registered fprobe which is on the fprobe
hash table before initializing fprobe.
The add_fprobe_hash() checks this re-register fprobe, but since
fprobe_init() clears hlist_array field, it is too late to check it.
It has to check the re-registration before touncing fprobe.
Link: https://lore.kernel.org/all/177669364845.132053.18375367916162315835.stgit@mhiramat.tok.corp.google.com/
Fixes: 4346ba160409 ("fprobe: Rewrite fprobe on function-graph tracer")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Diffstat (limited to 'kernel/trace/fprobe.c')
| -rw-r--r-- | kernel/trace/fprobe.c | 21 |
1 files changed, 10 insertions, 11 deletions
diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c index 56d145017902..af9ba7250874 100644 --- a/kernel/trace/fprobe.c +++ b/kernel/trace/fprobe.c @@ -4,6 +4,7 @@ */ #define pr_fmt(fmt) "fprobe: " fmt +#include <linux/cleanup.h> #include <linux/err.h> #include <linux/fprobe.h> #include <linux/kallsyms.h> @@ -107,7 +108,7 @@ static bool delete_fprobe_node(struct fprobe_hlist_node *node) } /* Check existence of the fprobe */ -static bool is_fprobe_still_exist(struct fprobe *fp) +static bool fprobe_registered(struct fprobe *fp) { struct hlist_head *head; struct fprobe_hlist *fph; @@ -120,7 +121,7 @@ static bool is_fprobe_still_exist(struct fprobe *fp) } return false; } -NOKPROBE_SYMBOL(is_fprobe_still_exist); +NOKPROBE_SYMBOL(fprobe_registered); static int add_fprobe_hash(struct fprobe *fp) { @@ -132,9 +133,6 @@ static int add_fprobe_hash(struct fprobe *fp) if (WARN_ON_ONCE(!fph)) return -EINVAL; - if (is_fprobe_still_exist(fp)) - return -EEXIST; - head = &fprobe_table[hash_ptr(fp, FPROBE_HASH_BITS)]; hlist_add_head_rcu(&fp->hlist_array->hlist, head); return 0; @@ -149,7 +147,7 @@ static int del_fprobe_hash(struct fprobe *fp) if (WARN_ON_ONCE(!fph)) return -EINVAL; - if (!is_fprobe_still_exist(fp)) + if (!fprobe_registered(fp)) return -ENOENT; fph->fp = NULL; @@ -480,7 +478,7 @@ static void fprobe_return(struct ftrace_graph_ret *trace, if (!fp) break; curr += FPROBE_HEADER_SIZE_IN_LONG; - if (is_fprobe_still_exist(fp) && !fprobe_disabled(fp)) { + if (fprobe_registered(fp) && !fprobe_disabled(fp)) { if (WARN_ON_ONCE(curr + size > size_words)) break; fp->exit_handler(fp, trace->func, ret_ip, fregs, @@ -839,12 +837,14 @@ int register_fprobe_ips(struct fprobe *fp, unsigned long *addrs, int num) struct fprobe_hlist *hlist_array; int ret, i; + guard(mutex)(&fprobe_mutex); + if (fprobe_registered(fp)) + return -EEXIST; + ret = fprobe_init(fp, addrs, num); if (ret) return ret; - mutex_lock(&fprobe_mutex); - hlist_array = fp->hlist_array; if (fprobe_is_ftrace(fp)) ret = fprobe_ftrace_add_ips(addrs, num); @@ -864,7 +864,6 @@ int register_fprobe_ips(struct fprobe *fp, unsigned long *addrs, int num) delete_fprobe_node(&hlist_array->array[i]); } } - mutex_unlock(&fprobe_mutex); if (ret) fprobe_fail_cleanup(fp); @@ -926,7 +925,7 @@ int unregister_fprobe(struct fprobe *fp) int ret = 0, i, count; mutex_lock(&fprobe_mutex); - if (!fp || !is_fprobe_still_exist(fp)) { + if (!fp || !fprobe_registered(fp)) { ret = -EINVAL; goto out; } |