diff options
| -rw-r--r-- | Documentation/dev-tools/checkpatch.rst | 23 | ||||
| -rwxr-xr-x | scripts/checkpatch.pl | 6 |
2 files changed, 29 insertions, 0 deletions
diff --git a/Documentation/dev-tools/checkpatch.rst b/Documentation/dev-tools/checkpatch.rst index 4dccd1036870..84ccb52e120b 100644 --- a/Documentation/dev-tools/checkpatch.rst +++ b/Documentation/dev-tools/checkpatch.rst @@ -1009,6 +1009,29 @@ Functions and Variables return bar; + **UNINITIALIZED_PTR_WITH_FREE** + Pointers with __free attribute should be declared at the place of use + and initialized (see include/linux/cleanup.h). In this case + declarations at the top of the function rule can be relaxed. Not doing + so may lead to undefined behavior as the memory assigned (garbage, + in case not initialized) to the pointer is freed automatically when + the pointer goes out of scope. + + Also see: https://lore.kernel.org/lkml/58fd478f408a34b578ee8d949c5c4b4da4d4f41d.camel@HansenPartnership.com/ + + Example:: + + type var __free(free_func); + ... // var not used, but, in future someone might add a return here + var = malloc(var_size); + ... + + should be initialized as:: + + ... + type var __free(free_func) = malloc(var_size); + ... + Permissions ----------- diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index d58ca9655ab7..c0250244cf7a 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -7732,6 +7732,12 @@ sub process { ERROR("MISSING_SENTINEL", "missing sentinel in ID array\n" . "$here\n$stat\n"); } } + +# check for uninitialized pointers with __free attribute + while ($line =~ /\*\s*($Ident)\s+__free\s*\(\s*$Ident\s*\)\s*[,;]/g) { + ERROR("UNINITIALIZED_PTR_WITH_FREE", + "pointer '$1' with __free attribute should be initialized\n" . $herecurr); + } } # If we have no input at all, then there is nothing to report on |