5.4-stable review patch. If anyone has any objections, please let me know.
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From: Zilin Guan zilin@seu.edu.cn
[ Upstream commit 80f0d631dcc76ee1b7755bfca1d8417d91d71414 ]
The function create_field_var() allocates memory for 'val' through create_hist_field() inside parse_atom(), and for 'var' through create_var(), which in turn allocates var->type and var->var.name internally. Simply calling kfree() to release these structures will result in memory leaks.
Use destroy_hist_field() to properly free 'val', and explicitly release the memory of var->type and var->var.name before freeing 'var' itself.
Link: https://patch.msgid.link/20251106120132.3639920-1-zilin@seu.edu.cn Fixes: 02205a6752f22 ("tracing: Add support for 'field variables'") Signed-off-by: Zilin Guan zilin@seu.edu.cn Signed-off-by: Steven Rostedt (Google) rostedt@goodmis.org Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/trace/trace_events_hist.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index 1ede6d41ab8da..21d0731874448 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -3634,14 +3634,16 @@ static struct field_var *create_field_var(struct hist_trigger_data *hist_data, var = create_var(hist_data, file, field_name, val->size, val->type); if (IS_ERR(var)) { hist_err(tr, HIST_ERR_VAR_CREATE_FIND_FAIL, errpos(field_name)); - kfree(val); + destroy_hist_field(val, 0); ret = PTR_ERR(var); goto err; }
field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL); if (!field_var) { - kfree(val); + destroy_hist_field(val, 0); + kfree_const(var->type); + kfree(var->var.name); kfree(var); ret = -ENOMEM; goto err;