lkml.org 
[lkml]   [2020]   [Jun]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH] coccinelle: misc: add array_size_dup script to detect missed overlow checks
    Date
    Detect an opencoded expression that is used before or after
    array_size()/array3_size()/struct_size() to compute the same size.

    Cc: Kees Cook <keescook@chromium.org>
    Signed-off-by: Denis Efremov <efremov@linux.com>
    ---
    scripts/coccinelle/misc/array_size_dup.cocci | 347 +++++++++++++++++++
    1 file changed, 347 insertions(+)
    create mode 100644 scripts/coccinelle/misc/array_size_dup.cocci

    diff --git a/scripts/coccinelle/misc/array_size_dup.cocci b/scripts/coccinelle/misc/array_size_dup.cocci
    new file mode 100644
    index 000000000000..08919a938754
    --- /dev/null
    +++ b/scripts/coccinelle/misc/array_size_dup.cocci
    @@ -0,0 +1,347 @@
    +// SPDX-License-Identifier: GPL-2.0-only
    +///
    +/// Check for array_size(), array3_size(), struct_size() duplicates.
    +/// Three types of patterns for these functions:
    +/// 1. An opencoded expression is used before array_size() to compute the same size
    +/// 2. An opencoded expression is used after array_size() to compute the same size
    +/// 3. Consecutive calls of array_size() with the same values
    +/// From security point of view only first case is relevant. These functions
    +/// perform arithmetic overflow check. Thus, if we use an opencoded expression
    +/// before a call to the *_size() function we can miss an overflow.
    +///
    +// Confidence: High
    +// Copyright: (C) 2020 Denis Efremov ISPRAS
    +// Options: --no-includes --include-headers --no-loops
    +
    +virtual context
    +virtual report
    +virtual org
    +
    +@as@
    +expression E1, E2;
    +@@
    +
    +array_size(E1, E2)
    +
    +@as_next@
    +expression subE1 <= as.E1;
    +expression as.E1;
    +expression subE2 <= as.E2;
    +expression as.E2;
    +expression E3;
    +position p1, p2;
    +@@
    +
    +* E1 * E2@p1
    + ... when != \(E1\|E2\|subE1\|subE2\)=E3
    + when != \(E1\|E2\|subE1\|subE2\)+=E3
    + when != \(E1\|E2\|subE1\|subE2\)-=E3
    + when != \(E1\|E2\|subE1\|subE2\)*=E3
    + when != \(&E1\|&E2\|&subE1\|&subE2\)
    +* array_size(E1, E2)@p2
    +
    +@as_prev@
    +expression subE1 <= as.E1;
    +expression as.E1;
    +expression subE2 <= as.E2;
    +expression as.E2;
    +expression E3;
    +position p1, p2;
    +@@
    +
    +* array_size(E1, E2)@p1
    + ... when != \(E1\|E2\|subE1\|subE2\)=E3
    + when != \(E1\|E2\|subE1\|subE2\)+=E3
    + when != \(E1\|E2\|subE1\|subE2\)-=E3
    + when != \(E1\|E2\|subE1\|subE2\)*=E3
    + when != \(&E1\|&E2\|&subE1\|&subE2\)
    +* E1 * E2@p2
    +
    +@as_dup@
    +expression subE1 <= as.E1;
    +expression as.E1;
    +expression subE2 <= as.E2;
    +expression as.E2;
    +expression E3;
    +position p1, p2;
    +@@
    +
    +* array_size(E1, E2)@p1
    + ... when != \(E1\|E2\|subE1\|subE2\)=E3
    + when != \(E1\|E2\|subE1\|subE2\)+=E3
    + when != \(E1\|E2\|subE1\|subE2\)-=E3
    + when != \(E1\|E2\|subE1\|subE2\)*=E3
    + when != \(&E1\|&E2\|&subE1\|&subE2\)
    +* array_size(E1, E2)@p2
    +
    +@as3@
    +expression E1, E2, E3;
    +@@
    +
    +array3_size(E1, E2, E3)
    +
    +@as3_next@
    +expression subE1 <= as3.E1;
    +expression as3.E1;
    +expression subE2 <= as3.E2;
    +expression as3.E2;
    +expression subE3 <= as3.E3;
    +expression as3.E3;
    +expression E4;
    +position p1, p2;
    +@@
    +
    +* E1 * E2 * E3@p1
    + ... when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)=E4
    + when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)+=E4
    + when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)-=E4
    + when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)*=E4
    + when != \(&E1\|&E2\|&E3\|&subE1\|&subE2\|&subE3\)
    +* array3_size(E1, E2, E3)@p2
    +
    +@as3_prev@
    +expression subE1 <= as3.E1;
    +expression as3.E1;
    +expression subE2 <= as3.E2;
    +expression as3.E2;
    +expression subE3 <= as3.E3;
    +expression as3.E3;
    +expression E4;
    +position p1, p2;
    +@@
    +
    +* array3_size(E1, E2, E3)@p1
    + ... when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)=E4
    + when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)+=E4
    + when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)-=E4
    + when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)*=E4
    + when != \(&E1\|&E2\|&E3\|&subE1\|&subE2\|&subE3\)
    +* E1 * E2 * E3@p2
    +
    +@as3_dup@
    +expression subE1 <= as3.E1;
    +expression as3.E1;
    +expression subE2 <= as3.E2;
    +expression as3.E2;
    +expression subE3 <= as3.E3;
    +expression as3.E3;
    +expression E4;
    +position p1, p2;
    +@@
    +
    +* array3_size(E1, E2, E3)@p1
    + ... when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)=E4
    + when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)+=E4
    + when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)-=E4
    + when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)*=E4
    + when != \(&E1\|&E2\|&E3\|&subE1\|&subE2\|&subE3\)
    +* array3_size(E1, E2, E3)@p2
    +
    +@ss@
    +expression E1, E2, E3;
    +@@
    +
    +struct_size(E1, E2, E3)
    +
    +@ss_next@
    +expression subE1 <= ss.E1;
    +expression ss.E1;
    +expression subE2 <= ss.E2;
    +expression ss.E2;
    +expression subE3 <= ss.E3;
    +expression ss.E3;
    +expression E4;
    +position p1, p2;
    +@@
    +
    +* E1 * E2 + E3@p1
    + ... when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)=E4
    + when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)+=E4
    + when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)-=E4
    + when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)*=E4
    + when != \(&E1\|&E2\|&E3\|&subE1\|&subE2\|&subE3\)
    +* struct_size(E1, E2, E3)@p2
    +
    +@ss_prev@
    +expression subE1 <= ss.E1;
    +expression ss.E1;
    +expression subE2 <= ss.E2;
    +expression ss.E2;
    +expression subE3 <= ss.E3;
    +expression ss.E3;
    +expression E4;
    +position p1, p2;
    +@@
    +
    +* struct_size(E1, E2, E3)@p1
    + ... when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)=E4
    + when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)+=E4
    + when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)-=E4
    + when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)*=E4
    + when != \(&E1\|&E2\|&E3\|&subE1\|&subE2\|&subE3\)
    +* E1 * E2 + E3@p2
    +
    +@ss_dup@
    +expression subE1 <= ss.E1;
    +expression ss.E1;
    +expression subE2 <= ss.E2;
    +expression ss.E2;
    +expression subE3 <= ss.E3;
    +expression ss.E3;
    +expression E4;
    +position p1, p2;
    +@@
    +
    +* struct_size(E1, E2, E3)@p1
    + ... when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)=E4
    + when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)+=E4
    + when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)-=E4
    + when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)*=E4
    + when != \(&E1\|&E2\|&E3\|&subE1\|&subE2\|&subE3\)
    +* struct_size(E1, E2, E3)@p2
    +
    +@script:python depends on report@
    +p1 << as_next.p1;
    +p2 << as_next.p2;
    +@@
    +
    +msg = "WARNING: array_size is used down the code (line %s) to compute the same size" % (p2[0].line)
    +coccilib.report.print_report(p1[0], msg)
    +
    +@script:python depends on org@
    +p1 << as_next.p1;
    +p2 << as_next.p2;
    +@@
    +
    +msg = "WARNING: array_size is used down the code (line %s) to compute the same size" % (p2[0].line)
    +coccilib.org.print_todo(p1[0], msg)
    +
    +@script:python depends on report@
    +p1 << as_prev.p1;
    +p2 << as_prev.p2;
    +@@
    +
    +msg = "WARNING: array_size is already used (line %s) to compute the same size" % (p1[0].line)
    +coccilib.report.print_report(p2[0], msg)
    +
    +@script:python depends on org@
    +p1 << as_prev.p1;
    +p2 << as_prev.p2;
    +@@
    +
    +msg = "WARNING: array_size is already used (line %s) to compute the same size" % (p1[0].line)
    +coccilib.org.print_todo(p2[0], msg)
    +
    +@script:python depends on report@
    +p1 << as_dup.p1;
    +p2 << as_dup.p2;
    +@@
    +
    +msg = "WARNING: same array_size (line %s)" % (p1[0].line)
    +coccilib.report.print_report(p2[0], msg)
    +
    +@script:python depends on org@
    +p1 << as_dup.p1;
    +p2 << as_dup.p2;
    +@@
    +
    +msg = "WARNING: same array_size (line %s)" % (p1[0].line)
    +coccilib.org.print_todo(p2[0], msg)
    +
    +
    +@script:python depends on report@
    +p1 << as3_next.p1;
    +p2 << as3_next.p2;
    +@@
    +
    +msg = "WARNING: array3_size is used down the code (line %s) to compute the same size" % (p2[0].line)
    +coccilib.report.print_report(p1[0], msg)
    +
    +@script:python depends on org@
    +p1 << as3_next.p1;
    +p2 << as3_next.p2;
    +@@
    +
    +msg = "WARNING: array3_size is used down the code (line %s) to compute the same size" % (p2[0].line)
    +coccilib.org.print_todo(p1[0], msg)
    +
    +@script:python depends on report@
    +p1 << as3_prev.p1;
    +p2 << as3_prev.p2;
    +@@
    +
    +msg = "WARNING: array3_size is already used (line %s) to compute the same size" % (p1[0].line)
    +coccilib.report.print_report(p2[0], msg)
    +
    +@script:python depends on org@
    +p1 << as3_prev.p1;
    +p2 << as3_prev.p2;
    +@@
    +
    +msg = "WARNING: array3_size is already used (line %s) to compute the same size" % (p1[0].line)
    +coccilib.org.print_todo(p2[0], msg)
    +
    +@script:python depends on report@
    +p1 << as3_dup.p1;
    +p2 << as3_dup.p2;
    +@@
    +
    +msg = "WARNING: same array3_size (line %s)" % (p1[0].line)
    +coccilib.report.print_report(p2[0], msg)
    +
    +@script:python depends on org@
    +p1 << as3_dup.p1;
    +p2 << as3_dup.p2;
    +@@
    +
    +msg = "WARNING: same array3_size (line %s)" % (p1[0].line)
    +coccilib.org.print_todo(p2[0], msg)
    +
    +
    +@script:python depends on report@
    +p1 << ss_next.p1;
    +p2 << ss_next.p2;
    +@@
    +
    +msg = "WARNING: struct_size is used down the code (line %s) to compute the same size" % (p2[0].line)
    +coccilib.report.print_report(p1[0], msg)
    +
    +@script:python depends on org@
    +p1 << ss_next.p1;
    +p2 << ss_next.p2;
    +@@
    +
    +msg = "WARNING: struct_size is used down the code (line %s) to compute the same size" % (p2[0].line)
    +coccilib.org.print_todo(p1[0], msg)
    +
    +@script:python depends on report@
    +p1 << ss_prev.p1;
    +p2 << ss_prev.p2;
    +@@
    +
    +msg = "WARNING: struct_size is already used (line %s) to compute the same size" % (p1[0].line)
    +coccilib.report.print_report(p2[0], msg)
    +
    +@script:python depends on org@
    +p1 << ss_prev.p1;
    +p2 << ss_prev.p2;
    +@@
    +
    +msg = "WARNING: struct_size is already used (line %s) to compute the same size" % (p1[0].line)
    +coccilib.org.print_todo(p2[0], msg)
    +
    +@script:python depends on report@
    +p1 << ss_dup.p1;
    +p2 << ss_dup.p2;
    +@@
    +
    +msg = "WARNING: same struct_size (line %s)" % (p1[0].line)
    +coccilib.report.print_report(p2[0], msg)
    +
    +@script:python depends on org@
    +p1 << ss_dup.p1;
    +p2 << ss_dup.p2;
    +@@
    +
    +msg = "WARNING: same struct_size (line %s)" % (p1[0].line)
    +coccilib.org.print_todo(p2[0], msg)
    --
    2.26.2
    \
     
     \ /
      Last update: 2020-06-15 12:21    [W:5.265 / U:0.012 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site