1/// Find missing unlocks. This semantic match considers the specific case 2/// where the unlock is missing from an if branch, and there is a lock 3/// before the if and an unlock after the if. False positives are due to 4/// cases where the if branch represents a case where the function is 5/// supposed to exit with the lock held, or where there is some preceding 6/// function call that releases the lock. 7/// 8// Confidence: Moderate 9// Copyright: (C) 2010-2012 Nicolas Palix. GPLv2. 10// Copyright: (C) 2010-2012 Julia Lawall, INRIA/LIP6. GPLv2. 11// Copyright: (C) 2010-2012 Gilles Muller, INRIA/LiP6. GPLv2. 12// URL: http://coccinelle.lip6.fr/ 13// Comments: 14// Options: --no-includes --include-headers 15 16virtual context 17virtual org 18virtual report 19 20@prelocked@ 21position p1,p; 22expression E1; 23@@ 24 25( 26mutex_lock@p1 27| 28mutex_trylock@p1 29| 30spin_lock@p1 31| 32spin_trylock@p1 33| 34read_lock@p1 35| 36read_trylock@p1 37| 38write_lock@p1 39| 40write_trylock@p1 41| 42read_lock_irq@p1 43| 44write_lock_irq@p1 45| 46read_lock_irqsave@p1 47| 48write_lock_irqsave@p1 49| 50spin_lock_irq@p1 51| 52spin_lock_irqsave@p1 53) (E1@p,...); 54 55@looped@ 56position r; 57@@ 58 59for(...;...;...) { <+... return@r ...; ...+> } 60 61@err exists@ 62expression E1; 63position prelocked.p; 64position up != prelocked.p1; 65position r!=looped.r; 66identifier lock,unlock; 67@@ 68 69*lock(E1@p,...); 70<+... when != E1 71if (...) { 72 ... when != E1 73* return@r ...; 74} 75...+> 76*unlock@up(E1,...); 77 78@script:python depends on org@ 79p << prelocked.p1; 80lock << err.lock; 81unlock << err.unlock; 82p2 << err.r; 83@@ 84 85cocci.print_main(lock,p) 86cocci.print_secs(unlock,p2) 87 88@script:python depends on report@ 89p << prelocked.p1; 90lock << err.lock; 91unlock << err.unlock; 92p2 << err.r; 93@@ 94 95msg = "preceding lock on line %s" % (p[0].line) 96coccilib.report.print_report(p2[0],msg) 97