* [ammarfaizi2-block:akpm/mm/mm-unstable 82/99] mm/mmap.c:516 vma_prepare() error: we previously assumed 'vp->vma' could be null (see line 505)
@ 2023-02-28 14:24 Dan Carpenter
2023-02-28 18:04 ` Suren Baghdasaryan
0 siblings, 1 reply; 4+ messages in thread
From: Dan Carpenter @ 2023-02-28 14:24 UTC (permalink / raw)
To: oe-kbuild, Suren Baghdasaryan
Cc: lkp, oe-kbuild-all, Ammar Faizi, GNU/Weeb Mailing List,
Andrew Morton, Linux Memory Management List
tree: https://github.com/ammarfaizi2/linux-block akpm/mm/mm-unstable
head: 61edd3b68c3185673c9b05dfe48038692964c73b
commit: f517f7ae341d933856cdf4d9d773027681ed5dff [82/99] mm/mmap: write-lock VMAs in vma_prepare before modifying them
config: i386-randconfig-m021 (https://download.01.org/0day-ci/archive/20230228/[email protected]/config)
compiler: gcc-11 (Debian 11.3.0-8) 11.3.0
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <[email protected]>
| Reported-by: Dan Carpenter <[email protected]>
| Link: https://lore.kernel.org/r/[email protected]/
smatch warnings:
mm/mmap.c:516 vma_prepare() error: we previously assumed 'vp->vma' could be null (see line 505)
vim +516 mm/mmap.c
440703e082b9c7 Liam R. Howlett 2023-01-20 503 static inline void vma_prepare(struct vma_prepare *vp)
440703e082b9c7 Liam R. Howlett 2023-01-20 504 {
f517f7ae341d93 Suren Baghdasaryan 2023-02-27 @505 if (vp->vma)
Check presumes that vp->vma can be NULL. On my other system (with
yesterday's linux-next code) vp->vma can never be NULL.
f517f7ae341d93 Suren Baghdasaryan 2023-02-27 506 vma_start_write(vp->vma);
f517f7ae341d93 Suren Baghdasaryan 2023-02-27 507 if (vp->adj_next)
f517f7ae341d93 Suren Baghdasaryan 2023-02-27 508 vma_start_write(vp->adj_next);
f517f7ae341d93 Suren Baghdasaryan 2023-02-27 509 /* vp->insert is always a newly created VMA, no need for locking */
f517f7ae341d93 Suren Baghdasaryan 2023-02-27 510 if (vp->remove)
f517f7ae341d93 Suren Baghdasaryan 2023-02-27 511 vma_start_write(vp->remove);
f517f7ae341d93 Suren Baghdasaryan 2023-02-27 512 if (vp->remove2)
f517f7ae341d93 Suren Baghdasaryan 2023-02-27 513 vma_start_write(vp->remove2);
f517f7ae341d93 Suren Baghdasaryan 2023-02-27 514
440703e082b9c7 Liam R. Howlett 2023-01-20 515 if (vp->file) {
440703e082b9c7 Liam R. Howlett 2023-01-20 @516 uprobe_munmap(vp->vma, vp->vma->vm_start, vp->vma->vm_end);
^^^^^^^
Uncheck dereference.
440703e082b9c7 Liam R. Howlett 2023-01-20 517
440703e082b9c7 Liam R. Howlett 2023-01-20 518 if (vp->adj_next)
440703e082b9c7 Liam R. Howlett 2023-01-20 519 uprobe_munmap(vp->adj_next, vp->adj_next->vm_start,
440703e082b9c7 Liam R. Howlett 2023-01-20 520 vp->adj_next->vm_end);
440703e082b9c7 Liam R. Howlett 2023-01-20 521
440703e082b9c7 Liam R. Howlett 2023-01-20 522 i_mmap_lock_write(vp->mapping);
440703e082b9c7 Liam R. Howlett 2023-01-20 523 if (vp->insert && vp->insert->vm_file) {
440703e082b9c7 Liam R. Howlett 2023-01-20 524 /*
440703e082b9c7 Liam R. Howlett 2023-01-20 525 * Put into interval tree now, so instantiated pages
440703e082b9c7 Liam R. Howlett 2023-01-20 526 * are visible to arm/parisc __flush_dcache_page
440703e082b9c7 Liam R. Howlett 2023-01-20 527 * throughout; but we cannot insert into address
440703e082b9c7 Liam R. Howlett 2023-01-20 528 * space until vma start or end is updated.
440703e082b9c7 Liam R. Howlett 2023-01-20 529 */
440703e082b9c7 Liam R. Howlett 2023-01-20 530 __vma_link_file(vp->insert,
440703e082b9c7 Liam R. Howlett 2023-01-20 531 vp->insert->vm_file->f_mapping);
440703e082b9c7 Liam R. Howlett 2023-01-20 532 }
440703e082b9c7 Liam R. Howlett 2023-01-20 533 }
440703e082b9c7 Liam R. Howlett 2023-01-20 534
440703e082b9c7 Liam R. Howlett 2023-01-20 535 if (vp->anon_vma) {
440703e082b9c7 Liam R. Howlett 2023-01-20 536 anon_vma_lock_write(vp->anon_vma);
440703e082b9c7 Liam R. Howlett 2023-01-20 537 anon_vma_interval_tree_pre_update_vma(vp->vma);
More unchecked dereferences.
440703e082b9c7 Liam R. Howlett 2023-01-20 538 if (vp->adj_next)
440703e082b9c7 Liam R. Howlett 2023-01-20 539 anon_vma_interval_tree_pre_update_vma(vp->adj_next);
440703e082b9c7 Liam R. Howlett 2023-01-20 540 }
440703e082b9c7 Liam R. Howlett 2023-01-20 541
440703e082b9c7 Liam R. Howlett 2023-01-20 542 if (vp->file) {
440703e082b9c7 Liam R. Howlett 2023-01-20 543 flush_dcache_mmap_lock(vp->mapping);
440703e082b9c7 Liam R. Howlett 2023-01-20 544 vma_interval_tree_remove(vp->vma, &vp->mapping->i_mmap);
440703e082b9c7 Liam R. Howlett 2023-01-20 545 if (vp->adj_next)
440703e082b9c7 Liam R. Howlett 2023-01-20 546 vma_interval_tree_remove(vp->adj_next,
440703e082b9c7 Liam R. Howlett 2023-01-20 547 &vp->mapping->i_mmap);
440703e082b9c7 Liam R. Howlett 2023-01-20 548 }
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [ammarfaizi2-block:akpm/mm/mm-unstable 82/99] mm/mmap.c:516 vma_prepare() error: we previously assumed 'vp->vma' could be null (see line 505)
2023-02-28 14:24 [ammarfaizi2-block:akpm/mm/mm-unstable 82/99] mm/mmap.c:516 vma_prepare() error: we previously assumed 'vp->vma' could be null (see line 505) Dan Carpenter
@ 2023-02-28 18:04 ` Suren Baghdasaryan
2023-03-01 2:28 ` Suren Baghdasaryan
0 siblings, 1 reply; 4+ messages in thread
From: Suren Baghdasaryan @ 2023-02-28 18:04 UTC (permalink / raw)
To: Dan Carpenter
Cc: oe-kbuild, lkp, oe-kbuild-all, Ammar Faizi, GNU/Weeb Mailing List,
Andrew Morton, Linux Memory Management List
On Tue, Feb 28, 2023 at 6:24 AM Dan Carpenter <[email protected]> wrote:
>
> tree: https://github.com/ammarfaizi2/linux-block akpm/mm/mm-unstable
> head: 61edd3b68c3185673c9b05dfe48038692964c73b
> commit: f517f7ae341d933856cdf4d9d773027681ed5dff [82/99] mm/mmap: write-lock VMAs in vma_prepare before modifying them
> config: i386-randconfig-m021 (https://download.01.org/0day-ci/archive/20230228/[email protected]/config)
> compiler: gcc-11 (Debian 11.3.0-8) 11.3.0
>
> If you fix the issue, kindly add following tag where applicable
> | Reported-by: kernel test robot <[email protected]>
> | Reported-by: Dan Carpenter <[email protected]>
> | Link: https://lore.kernel.org/r/[email protected]/
Thanks for reporting!
>
> smatch warnings:
> mm/mmap.c:516 vma_prepare() error: we previously assumed 'vp->vma' could be null (see line 505)
>
> vim +516 mm/mmap.c
>
> 440703e082b9c7 Liam R. Howlett 2023-01-20 503 static inline void vma_prepare(struct vma_prepare *vp)
> 440703e082b9c7 Liam R. Howlett 2023-01-20 504 {
> f517f7ae341d93 Suren Baghdasaryan 2023-02-27 @505 if (vp->vma)
>
> Check presumes that vp->vma can be NULL. On my other system (with
> yesterday's linux-next code) vp->vma can never be NULL.
I think the check here is not needed since vp->vma should always be
non-NULL. I'll double-check and will remove it if that is confirmed.
Thanks,
Suren.
>
> f517f7ae341d93 Suren Baghdasaryan 2023-02-27 506 vma_start_write(vp->vma);
> f517f7ae341d93 Suren Baghdasaryan 2023-02-27 507 if (vp->adj_next)
> f517f7ae341d93 Suren Baghdasaryan 2023-02-27 508 vma_start_write(vp->adj_next);
> f517f7ae341d93 Suren Baghdasaryan 2023-02-27 509 /* vp->insert is always a newly created VMA, no need for locking */
> f517f7ae341d93 Suren Baghdasaryan 2023-02-27 510 if (vp->remove)
> f517f7ae341d93 Suren Baghdasaryan 2023-02-27 511 vma_start_write(vp->remove);
> f517f7ae341d93 Suren Baghdasaryan 2023-02-27 512 if (vp->remove2)
> f517f7ae341d93 Suren Baghdasaryan 2023-02-27 513 vma_start_write(vp->remove2);
> f517f7ae341d93 Suren Baghdasaryan 2023-02-27 514
> 440703e082b9c7 Liam R. Howlett 2023-01-20 515 if (vp->file) {
> 440703e082b9c7 Liam R. Howlett 2023-01-20 @516 uprobe_munmap(vp->vma, vp->vma->vm_start, vp->vma->vm_end);
> ^^^^^^^
> Uncheck dereference.
>
> 440703e082b9c7 Liam R. Howlett 2023-01-20 517
> 440703e082b9c7 Liam R. Howlett 2023-01-20 518 if (vp->adj_next)
> 440703e082b9c7 Liam R. Howlett 2023-01-20 519 uprobe_munmap(vp->adj_next, vp->adj_next->vm_start,
> 440703e082b9c7 Liam R. Howlett 2023-01-20 520 vp->adj_next->vm_end);
> 440703e082b9c7 Liam R. Howlett 2023-01-20 521
> 440703e082b9c7 Liam R. Howlett 2023-01-20 522 i_mmap_lock_write(vp->mapping);
> 440703e082b9c7 Liam R. Howlett 2023-01-20 523 if (vp->insert && vp->insert->vm_file) {
> 440703e082b9c7 Liam R. Howlett 2023-01-20 524 /*
> 440703e082b9c7 Liam R. Howlett 2023-01-20 525 * Put into interval tree now, so instantiated pages
> 440703e082b9c7 Liam R. Howlett 2023-01-20 526 * are visible to arm/parisc __flush_dcache_page
> 440703e082b9c7 Liam R. Howlett 2023-01-20 527 * throughout; but we cannot insert into address
> 440703e082b9c7 Liam R. Howlett 2023-01-20 528 * space until vma start or end is updated.
> 440703e082b9c7 Liam R. Howlett 2023-01-20 529 */
> 440703e082b9c7 Liam R. Howlett 2023-01-20 530 __vma_link_file(vp->insert,
> 440703e082b9c7 Liam R. Howlett 2023-01-20 531 vp->insert->vm_file->f_mapping);
> 440703e082b9c7 Liam R. Howlett 2023-01-20 532 }
> 440703e082b9c7 Liam R. Howlett 2023-01-20 533 }
> 440703e082b9c7 Liam R. Howlett 2023-01-20 534
> 440703e082b9c7 Liam R. Howlett 2023-01-20 535 if (vp->anon_vma) {
> 440703e082b9c7 Liam R. Howlett 2023-01-20 536 anon_vma_lock_write(vp->anon_vma);
> 440703e082b9c7 Liam R. Howlett 2023-01-20 537 anon_vma_interval_tree_pre_update_vma(vp->vma);
>
> More unchecked dereferences.
>
> 440703e082b9c7 Liam R. Howlett 2023-01-20 538 if (vp->adj_next)
> 440703e082b9c7 Liam R. Howlett 2023-01-20 539 anon_vma_interval_tree_pre_update_vma(vp->adj_next);
> 440703e082b9c7 Liam R. Howlett 2023-01-20 540 }
> 440703e082b9c7 Liam R. Howlett 2023-01-20 541
> 440703e082b9c7 Liam R. Howlett 2023-01-20 542 if (vp->file) {
> 440703e082b9c7 Liam R. Howlett 2023-01-20 543 flush_dcache_mmap_lock(vp->mapping);
> 440703e082b9c7 Liam R. Howlett 2023-01-20 544 vma_interval_tree_remove(vp->vma, &vp->mapping->i_mmap);
> 440703e082b9c7 Liam R. Howlett 2023-01-20 545 if (vp->adj_next)
> 440703e082b9c7 Liam R. Howlett 2023-01-20 546 vma_interval_tree_remove(vp->adj_next,
> 440703e082b9c7 Liam R. Howlett 2023-01-20 547 &vp->mapping->i_mmap);
> 440703e082b9c7 Liam R. Howlett 2023-01-20 548 }
>
> --
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests
>
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [ammarfaizi2-block:akpm/mm/mm-unstable 82/99] mm/mmap.c:516 vma_prepare() error: we previously assumed 'vp->vma' could be null (see line 505)
2023-02-28 18:04 ` Suren Baghdasaryan
@ 2023-03-01 2:28 ` Suren Baghdasaryan
2023-03-01 5:00 ` Dan Carpenter
0 siblings, 1 reply; 4+ messages in thread
From: Suren Baghdasaryan @ 2023-03-01 2:28 UTC (permalink / raw)
To: Dan Carpenter
Cc: oe-kbuild, lkp, oe-kbuild-all, Ammar Faizi, GNU/Weeb Mailing List,
Andrew Morton, Linux Memory Management List
On Tue, Feb 28, 2023 at 10:04 AM Suren Baghdasaryan <[email protected]> wrote:
>
> On Tue, Feb 28, 2023 at 6:24 AM Dan Carpenter <[email protected]> wrote:
> >
> > tree: https://github.com/ammarfaizi2/linux-block akpm/mm/mm-unstable
> > head: 61edd3b68c3185673c9b05dfe48038692964c73b
> > commit: f517f7ae341d933856cdf4d9d773027681ed5dff [82/99] mm/mmap: write-lock VMAs in vma_prepare before modifying them
> > config: i386-randconfig-m021 (https://download.01.org/0day-ci/archive/20230228/[email protected]/config)
> > compiler: gcc-11 (Debian 11.3.0-8) 11.3.0
> >
> > If you fix the issue, kindly add following tag where applicable
> > | Reported-by: kernel test robot <[email protected]>
> > | Reported-by: Dan Carpenter <[email protected]>
> > | Link: https://lore.kernel.org/r/[email protected]/
>
> Thanks for reporting!
>
> >
> > smatch warnings:
> > mm/mmap.c:516 vma_prepare() error: we previously assumed 'vp->vma' could be null (see line 505)
> >
> > vim +516 mm/mmap.c
> >
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 503 static inline void vma_prepare(struct vma_prepare *vp)
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 504 {
> > f517f7ae341d93 Suren Baghdasaryan 2023-02-27 @505 if (vp->vma)
> >
> > Check presumes that vp->vma can be NULL. On my other system (with
> > yesterday's linux-next code) vp->vma can never be NULL.
>
> I think the check here is not needed since vp->vma should always be
> non-NULL. I'll double-check and will remove it if that is confirmed.
Fix is posted at
https://lore.kernel.org/all/[email protected]/
> Thanks,
> Suren.
>
> >
> > f517f7ae341d93 Suren Baghdasaryan 2023-02-27 506 vma_start_write(vp->vma);
> > f517f7ae341d93 Suren Baghdasaryan 2023-02-27 507 if (vp->adj_next)
> > f517f7ae341d93 Suren Baghdasaryan 2023-02-27 508 vma_start_write(vp->adj_next);
> > f517f7ae341d93 Suren Baghdasaryan 2023-02-27 509 /* vp->insert is always a newly created VMA, no need for locking */
> > f517f7ae341d93 Suren Baghdasaryan 2023-02-27 510 if (vp->remove)
> > f517f7ae341d93 Suren Baghdasaryan 2023-02-27 511 vma_start_write(vp->remove);
> > f517f7ae341d93 Suren Baghdasaryan 2023-02-27 512 if (vp->remove2)
> > f517f7ae341d93 Suren Baghdasaryan 2023-02-27 513 vma_start_write(vp->remove2);
> > f517f7ae341d93 Suren Baghdasaryan 2023-02-27 514
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 515 if (vp->file) {
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 @516 uprobe_munmap(vp->vma, vp->vma->vm_start, vp->vma->vm_end);
> > ^^^^^^^
> > Uncheck dereference.
> >
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 517
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 518 if (vp->adj_next)
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 519 uprobe_munmap(vp->adj_next, vp->adj_next->vm_start,
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 520 vp->adj_next->vm_end);
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 521
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 522 i_mmap_lock_write(vp->mapping);
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 523 if (vp->insert && vp->insert->vm_file) {
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 524 /*
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 525 * Put into interval tree now, so instantiated pages
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 526 * are visible to arm/parisc __flush_dcache_page
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 527 * throughout; but we cannot insert into address
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 528 * space until vma start or end is updated.
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 529 */
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 530 __vma_link_file(vp->insert,
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 531 vp->insert->vm_file->f_mapping);
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 532 }
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 533 }
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 534
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 535 if (vp->anon_vma) {
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 536 anon_vma_lock_write(vp->anon_vma);
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 537 anon_vma_interval_tree_pre_update_vma(vp->vma);
> >
> > More unchecked dereferences.
> >
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 538 if (vp->adj_next)
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 539 anon_vma_interval_tree_pre_update_vma(vp->adj_next);
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 540 }
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 541
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 542 if (vp->file) {
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 543 flush_dcache_mmap_lock(vp->mapping);
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 544 vma_interval_tree_remove(vp->vma, &vp->mapping->i_mmap);
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 545 if (vp->adj_next)
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 546 vma_interval_tree_remove(vp->adj_next,
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 547 &vp->mapping->i_mmap);
> > 440703e082b9c7 Liam R. Howlett 2023-01-20 548 }
> >
> > --
> > 0-DAY CI Kernel Test Service
> > https://github.com/intel/lkp-tests
> >
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [ammarfaizi2-block:akpm/mm/mm-unstable 82/99] mm/mmap.c:516 vma_prepare() error: we previously assumed 'vp->vma' could be null (see line 505)
2023-03-01 2:28 ` Suren Baghdasaryan
@ 2023-03-01 5:00 ` Dan Carpenter
0 siblings, 0 replies; 4+ messages in thread
From: Dan Carpenter @ 2023-03-01 5:00 UTC (permalink / raw)
To: Suren Baghdasaryan
Cc: oe-kbuild, lkp, oe-kbuild-all, Ammar Faizi, GNU/Weeb Mailing List,
Andrew Morton, Linux Memory Management List
On Tue, Feb 28, 2023 at 06:28:36PM -0800, Suren Baghdasaryan wrote:
> On Tue, Feb 28, 2023 at 10:04 AM Suren Baghdasaryan <[email protected]> wrote:
> >
> > On Tue, Feb 28, 2023 at 6:24 AM Dan Carpenter <[email protected]> wrote:
> > >
> > > tree: https://github.com/ammarfaizi2/linux-block akpm/mm/mm-unstable
> > > head: 61edd3b68c3185673c9b05dfe48038692964c73b
> > > commit: f517f7ae341d933856cdf4d9d773027681ed5dff [82/99] mm/mmap: write-lock VMAs in vma_prepare before modifying them
> > > config: i386-randconfig-m021 (https://download.01.org/0day-ci/archive/20230228/[email protected]/config)
> > > compiler: gcc-11 (Debian 11.3.0-8) 11.3.0
> > >
> > > If you fix the issue, kindly add following tag where applicable
> > > | Reported-by: kernel test robot <[email protected]>
> > > | Reported-by: Dan Carpenter <[email protected]>
> > > | Link: https://lore.kernel.org/r/[email protected]/
> >
> > Thanks for reporting!
> >
> > >
> > > smatch warnings:
> > > mm/mmap.c:516 vma_prepare() error: we previously assumed 'vp->vma' could be null (see line 505)
> > >
> > > vim +516 mm/mmap.c
> > >
> > > 440703e082b9c7 Liam R. Howlett 2023-01-20 503 static inline void vma_prepare(struct vma_prepare *vp)
> > > 440703e082b9c7 Liam R. Howlett 2023-01-20 504 {
> > > f517f7ae341d93 Suren Baghdasaryan 2023-02-27 @505 if (vp->vma)
> > >
> > > Check presumes that vp->vma can be NULL. On my other system (with
> > > yesterday's linux-next code) vp->vma can never be NULL.
> >
> > I think the check here is not needed since vp->vma should always be
> > non-NULL. I'll double-check and will remove it if that is confirmed.
>
> Fix is posted at
> https://lore.kernel.org/all/[email protected]/
Thanks!
regards,
dan carpenter
^ permalink raw reply [flat|nested] 4+ messages in thread
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2023-02-28 14:24 [ammarfaizi2-block:akpm/mm/mm-unstable 82/99] mm/mmap.c:516 vma_prepare() error: we previously assumed 'vp->vma' could be null (see line 505) Dan Carpenter
2023-02-28 18:04 ` Suren Baghdasaryan
2023-03-01 2:28 ` Suren Baghdasaryan
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