Hi,
Static analysis on linux-next with Coverity has detected a potential issue in the following commit:
commit 3f0638a0333bfdd0549985aa620f2ab69737af47 Author: Jaroslav Kysela perex@perex.cz Date: Wed Mar 17 18:29:41 2021 +0100
ALSA: control - add layer registration routines
The static analysis is as follows:
2072 void snd_ctl_disconnect_layer(struct snd_ctl_layer_ops *lops) 2073 { 2074 struct snd_ctl_layer_ops *lops2, *prev_lops2; 2075 2076 down_write(&snd_ctl_layer_rwsem);
assignment: Assigning: prev_lops2 = NULL.
2077 for (lops2 = snd_ctl_layer, prev_lops2 = NULL; lops2; lops2 = lops2->next) 2078 if (lops2 == lops) {
null: At condition prev_lops2, the value of prev_lops2 must be NULL. dead_error_condition: The condition !prev_lops2 must be true.
2079 if (!prev_lops2) 2080 snd_ctl_layer = lops->next; 2081 else
'Constant' variable guards dead code (DEADCODE) dead_error_line: Execution cannot reach this statement: prev_lops2->next = lops->next;. Local variable prev_lops2 is assigned only once, to a constant value, making it effectively constant throughout its scope. If this is not the intent, examine the logic to see if there is a missing assignment that would make prev_lops2 not remain constant.
2082 prev_lops2->next = lops->next; 2083 break; 2084 } 2085 up_write(&snd_ctl_layer_rwsem); 2086 }
I couldn't quite figure out the original intent of the prev_lops use, so I'd thought I'd report this issue as the code does look incorrect.
Colin