Check that alloc and free types of functions match each other. Signed-off-by: Denis Efremov <efre...@linux.com> --- Changes in v2: - Lines are limited to 80 characters where possible - Confidence changed from High to Medium because of fs/btrfs/send.c:1119 false-positive - __vmalloc_area_node() explicitly excluded from analysis instead of !(file in "mm/vmalloc.c") condition Changes in v3: - prints style in org && report modes changed for python2 Changes in v4: - missing msg argument to print_todo fixed Changes in v5: - fix position p in kfree rule - move @kok and @v positions in choice rule after the arguments - remove kvmalloc suggestions Changes in v6: - more asterisks added in context mode - second @kok added to the choice rule Changes in v7: - file renamed to kfree_mismatch.cocci - python function relevant() removed - additional rule for filtering free positions added - btrfs false-positive fixed - confidence level changed to high - kvfree_switch rule added - names for position variables changed to @a (alloc) and @f (free)
scripts/coccinelle/api/kfree_mismatch.cocci | 229 ++++++++++++++++++++ 1 file changed, 229 insertions(+) create mode 100644 scripts/coccinelle/api/kfree_mismatch.cocci diff --git a/scripts/coccinelle/api/kfree_mismatch.cocci b/scripts/coccinelle/api/kfree_mismatch.cocci new file mode 100644 index 000000000000..9e9ef9fd7a25 --- /dev/null +++ b/scripts/coccinelle/api/kfree_mismatch.cocci @@ -0,0 +1,229 @@ +// SPDX-License-Identifier: GPL-2.0-only +/// +/// Check that kvmalloc'ed memory is freed by kfree functions, +/// vmalloc'ed by vfree functions and kvmalloc'ed by kvfree +/// functions. +/// +// Confidence: High +// Copyright: (C) 2020 Denis Efremov ISPRAS +// Options: --no-includes --include-headers +// + +virtual patch +virtual report +virtual org +virtual context + +@alloc@ +expression E, E1; +position kok, vok; +@@ + +( + if (...) { + ... + E = \(kmalloc\|kzalloc\|krealloc\|kcalloc\| + kmalloc_node\|kzalloc_node\|kmalloc_array\| + kmalloc_array_node\|kcalloc_node\)(...)@kok + ... + } else { + ... + E = \(vmalloc\|vzalloc\|vmalloc_user\|vmalloc_node\| + vzalloc_node\|vmalloc_exec\|vmalloc_32\| + vmalloc_32_user\|__vmalloc\|__vmalloc_node_range\| + __vmalloc_node\)(...)@vok + ... + } +| + E = \(kmalloc\|kzalloc\|krealloc\|kcalloc\|kmalloc_node\|kzalloc_node\| + kmalloc_array\|kmalloc_array_node\|kcalloc_node\)(...)@kok + ... when != E = E1 + when any + if (E == NULL) { + ... + E = \(vmalloc\|vzalloc\|vmalloc_user\|vmalloc_node\| + vzalloc_node\|vmalloc_exec\|vmalloc_32\| + vmalloc_32_user\|__vmalloc\|__vmalloc_node_range\| + __vmalloc_node\)(...)@vok + ... + } +) + +@free@ +expression E; +position fok; +@@ + + E = \(kvmalloc\|kvzalloc\|kvcalloc\|kvzalloc_node\|kvmalloc_node\| + kvmalloc_array\)(...) + ... + kvfree(E)@fok + +@vfree depends on !patch@ +expression E; +position a != alloc.kok; +position f != free.fok; +@@ + +* E = \(kmalloc\|kzalloc\|krealloc\|kcalloc\|kmalloc_node\| +* kzalloc_node\|kmalloc_array\|kmalloc_array_node\| +* kcalloc_node\)(...)@a + ... when != if (...) { ... E = \(vmalloc\|vzalloc\|vmalloc_user\|vmalloc_node\|vzalloc_node\|vmalloc_exec\|vmalloc_32\|vmalloc_32_user\|__vmalloc\|__vmalloc_node_range\|__vmalloc_node\)(...); ... } + when != is_vmalloc_addr(E) + when any +* \(vfree\|vfree_atomic\|kvfree\)(E)@f + +@depends on patch exists@ +expression E; +position a != alloc.kok; +position f != free.fok; +@@ + + E = \(kmalloc\|kzalloc\|krealloc\|kcalloc\|kmalloc_node\| + kzalloc_node\|kmalloc_array\|kmalloc_array_node\| + kcalloc_node\)(...)@a + ... when != if (...) { ... E = \(vmalloc\|vzalloc\|vmalloc_user\|vmalloc_node\|vzalloc_node\|vmalloc_exec\|vmalloc_32\|vmalloc_32_user\|__vmalloc\|__vmalloc_node_range\|__vmalloc_node\)(...); ... } + when != is_vmalloc_addr(E) + when any +- \(vfree\|vfree_atomic\|kvfree\)(E)@f ++ kfree(E) + +@kfree depends on !patch@ +expression E; +position a != alloc.vok; +position f != free.fok; +@@ + +* E = \(vmalloc\|vzalloc\|vmalloc_user\|vmalloc_node\|vzalloc_node\| +* vmalloc_exec\|vmalloc_32\|vmalloc_32_user\|__vmalloc\| +* __vmalloc_node_range\|__vmalloc_node\)(...)@a + ... when != is_vmalloc_addr(E) + when any +* \(kfree\|kzfree\|kvfree\)(E)@f + +@depends on patch exists@ +expression E; +position a != alloc.vok; +position f != free.fok; +@@ + + E = \(vmalloc\|vzalloc\|vmalloc_user\|vmalloc_node\|vzalloc_node\| + vmalloc_exec\|vmalloc_32\|vmalloc_32_user\|__vmalloc\| + __vmalloc_node_range\|__vmalloc_node\)(...)@a + ... when != is_vmalloc_addr(E) + when any +- \(kfree\|kvfree\)(E)@f ++ vfree(E) + +@kvfree depends on !patch@ +expression E; +position a, f; +@@ + +* E = \(kvmalloc\|kvzalloc\|kvcalloc\|kvzalloc_node\|kvmalloc_node\| +* kvmalloc_array\)(...)@a + ... when != is_vmalloc_addr(E) + when any +* \(kfree\|kzfree\|vfree\|vfree_atomic\)(E)@f + +@depends on patch exists@ +expression E; +@@ + + E = \(kvmalloc\|kvzalloc\|kvcalloc\|kvzalloc_node\|kvmalloc_node\| + kvmalloc_array\)(...) + ... when != is_vmalloc_addr(E) + when any +- \(kfree\|vfree\)(E) ++ kvfree(E) + +@kvfree_switch depends on !patch@ +expression alloc.E; +position f != free.fok; +@@ + + ... when != is_vmalloc_addr(E) + when any +* \(kfree\|kzfree\|vfree\|vfree_atomic\)(E)@f + +@depends on patch exists@ +expression alloc.E; +position f != free.fok; +@@ + + ... when != is_vmalloc_addr(E) + when any +( +- \(kfree\|vfree\)(E)@f ++ kvfree(E) +| +- kzfree(E)@f ++ kvfree_sensitive(E) +) + +@script: python depends on report@ +a << vfree.a; +f << vfree.f; +@@ + +msg = "WARNING: kmalloc is used to allocate this memory at line %s" % (a[0].line) +coccilib.report.print_report(f[0], msg) + +@script: python depends on org@ +a << vfree.a; +f << vfree.f; +@@ + +msg = "WARNING: kmalloc is used to allocate this memory at line %s" % (a[0].line) +coccilib.org.print_todo(f[0], msg) + +@script: python depends on report@ +a << kfree.a; +f << kfree.f; +@@ + +msg = "WARNING: vmalloc is used to allocate this memory at line %s" % (a[0].line) +coccilib.report.print_report(f[0], msg) + +@script: python depends on org@ +a << kfree.a; +f << kfree.f; +@@ + +msg = "WARNING: vmalloc is used to allocate this memory at line %s" % (a[0].line) +coccilib.org.print_todo(f[0], msg) + +@script: python depends on report@ +a << kvfree.a; +f << kvfree.f; +@@ + +msg = "WARNING: kvmalloc is used to allocate this memory at line %s" % (a[0].line) +coccilib.report.print_report(f[0], msg) + +@script: python depends on org@ +a << kvfree.a; +f << kvfree.f; +@@ + +msg = "WARNING: kvmalloc is used to allocate this memory at line %s" % (a[0].line) +coccilib.org.print_todo(f[0], msg) + +@script: python depends on report@ +ka << alloc.kok; +va << alloc.vok; +f << kvfree_switch.f; +@@ + +msg = "WARNING: kmalloc (line %s) && vmalloc (line %s) are used to allocate this memory" % (ka[0].line, va[0].line) +coccilib.report.print_report(f[0], msg) + +@script: python depends on org@ +ka << alloc.kok; +va << alloc.vok; +f << kvfree_switch.f; +@@ + +msg = "WARNING: kmalloc (line %s) && vmalloc (line %s) are used to allocate this memory" % (ka[0].line, va[0].line) +coccilib.org.print_todo(f[0], msg) + -- 2.26.2 _______________________________________________ Cocci mailing list Cocci@systeme.lip6.fr https://systeme.lip6.fr/mailman/listinfo/cocci