Hi,
Static analysis on linux-next with Coverity has detected a potential
issue in the following commit:
commit 3f0638a0333bfdd0549985aa620f2ab69737af47
Author: Jaroslav Kysela <perex@xxxxxxxx>
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
