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* [Bug middle-end/102453] New: buffer overflow by atomic built-ins not diagnosed @ 2021-09-22 15:17 msebor at gcc dot gnu.org 2021-09-22 15:17 ` [Bug middle-end/102453] " msebor at gcc dot gnu.org ` (3 more replies) 0 siblings, 4 replies; 5+ messages in thread From: msebor at gcc dot gnu.org @ 2021-09-22 15:17 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102453 Bug ID: 102453 Summary: buffer overflow by atomic built-ins not diagnosed Product: gcc Version: 12.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: middle-end Assignee: unassigned at gcc dot gnu.org Reporter: msebor at gcc dot gnu.org Target Milestone: --- The buffer overflow by the straight assignment in f() below is diagnosed as expected but the equivalent overflow by the atomic built-in in g() is not even though both should be. The problem is simply that due to an oversight, the access warnings lack support for atomic built-ins. $ cat y.c && gcc -O2 -S -Wall -fdump-tree-optimized=/dev/stdout y.c extern _Atomic char x; void f (void) { long *p = (long*)&x; *p = 0; } void g (void) { long *p = (long*)&x; __atomic_store_n (p, 0, 0); } y.c: In function ‘f’: y.c:7:3: warning: array subscript ‘long int[0]’ is partly outside array bounds of ‘_Atomic char[1]’ [-Warray-bounds] 7 | *p = 0; | ^~ y.c:1:21: note: object ‘x’ of size 1 1 | extern _Atomic char x; | ^ ;; Function f (f, funcdef_no=0, decl_uid=1979, cgraph_uid=1, symbol_order=0) void f () { <bb 2> [local count: 1073741824]: MEM[(long int *)&x] = 0; return; } ;; Function g (g, funcdef_no=1, decl_uid=1983, cgraph_uid=2, symbol_order=1) void g () { <bb 2> [local count: 1073741824]: __atomic_store_8 (&x, 0, 0); [tail call] return; } ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug middle-end/102453] buffer overflow by atomic built-ins not diagnosed 2021-09-22 15:17 [Bug middle-end/102453] New: buffer overflow by atomic built-ins not diagnosed msebor at gcc dot gnu.org @ 2021-09-22 15:17 ` msebor at gcc dot gnu.org 2021-10-11 21:49 ` msebor at gcc dot gnu.org ` (2 subsequent siblings) 3 siblings, 0 replies; 5+ messages in thread From: msebor at gcc dot gnu.org @ 2021-09-22 15:17 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102453 Martin Sebor <msebor at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Assignee|unassigned at gcc dot gnu.org |msebor at gcc dot gnu.org Status|UNCONFIRMED |ASSIGNED Keywords| |diagnostic Blocks| |56456 Ever confirmed|0 |1 Last reconfirmed| |2021-09-22 Referenced Bugs: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56456 [Bug 56456] [meta-bug] bogus/missing -Warray-bounds ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug middle-end/102453] buffer overflow by atomic built-ins not diagnosed 2021-09-22 15:17 [Bug middle-end/102453] New: buffer overflow by atomic built-ins not diagnosed msebor at gcc dot gnu.org 2021-09-22 15:17 ` [Bug middle-end/102453] " msebor at gcc dot gnu.org @ 2021-10-11 21:49 ` msebor at gcc dot gnu.org 2021-10-26 22:54 ` cvs-commit at gcc dot gnu.org 2021-10-26 23:02 ` msebor at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: msebor at gcc dot gnu.org @ 2021-10-11 21:49 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102453 Martin Sebor <msebor at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Keywords| |patch --- Comment #1 from Martin Sebor <msebor at gcc dot gnu.org> --- Patch: https://gcc.gnu.org/pipermail/gcc-patches/2021-October/581396.html ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug middle-end/102453] buffer overflow by atomic built-ins not diagnosed 2021-09-22 15:17 [Bug middle-end/102453] New: buffer overflow by atomic built-ins not diagnosed msebor at gcc dot gnu.org 2021-09-22 15:17 ` [Bug middle-end/102453] " msebor at gcc dot gnu.org 2021-10-11 21:49 ` msebor at gcc dot gnu.org @ 2021-10-26 22:54 ` cvs-commit at gcc dot gnu.org 2021-10-26 23:02 ` msebor at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: cvs-commit at gcc dot gnu.org @ 2021-10-26 22:54 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102453 --- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Martin Sebor <msebor@gcc.gnu.org>: https://gcc.gnu.org/g:88b504b7a8c5affb0ffa97990d22af2b199e36ed commit r12-4725-g88b504b7a8c5affb0ffa97990d22af2b199e36ed Author: Martin Sebor <msebor@redhat.com> Date: Tue Oct 26 14:34:16 2021 -0600 Detect overflow by atomic functions [PR102453]. Resolves: PR middle-end/102453 - buffer overflow by atomic built-ins not diagnosed gcc/ChangeLog: PR middle-end/102453 * gimple-ssa-warn-access.cc (pass_waccess::check_atomic_builtin): New. (pass_waccess::check_atomic_builtin): Call it. gcc/testsuite/ChangeLog: PR middle-end/102453 * gcc.dg/Warray-bounds-90.c: New test. * gcc.dg/Wstringop-overflow-77.c: New test. * gcc.dg/Wstringop-overflow-78.c: New test. * gcc.dg/Wstringop-overflow-79.c: New test. * gcc.dg/Wstringop-overflow-80.c: New test. * c-c++-common/gomp/atomic-4.c: Avoid an out-of-bounds access. ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug middle-end/102453] buffer overflow by atomic built-ins not diagnosed 2021-09-22 15:17 [Bug middle-end/102453] New: buffer overflow by atomic built-ins not diagnosed msebor at gcc dot gnu.org ` (2 preceding siblings ...) 2021-10-26 22:54 ` cvs-commit at gcc dot gnu.org @ 2021-10-26 23:02 ` msebor at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: msebor at gcc dot gnu.org @ 2021-10-26 23:02 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102453 Martin Sebor <msebor at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Resolution|--- |FIXED Status|ASSIGNED |RESOLVED Target Milestone|--- |12.0 --- Comment #3 from Martin Sebor <msebor at gcc dot gnu.org> --- Done in r12-4725. ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2021-10-26 23:02 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2021-09-22 15:17 [Bug middle-end/102453] New: buffer overflow by atomic built-ins not diagnosed msebor at gcc dot gnu.org 2021-09-22 15:17 ` [Bug middle-end/102453] " msebor at gcc dot gnu.org 2021-10-11 21:49 ` msebor at gcc dot gnu.org 2021-10-26 22:54 ` cvs-commit at gcc dot gnu.org 2021-10-26 23:02 ` msebor at gcc dot gnu.org
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