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From: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> stable inclusion from stable-v5.10.231 commit 7a450540c82f4fa99f60727acd5b402f3d1786f7 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IB7051 CVE: CVE-2024-53096 Reference: https://lore.kernel.org/linux-mm/99f72d6dc52835126ca6d2e79732d397f6bfa20b.17... -------------------------------- [ Upstream commit 4080ef1579b2413435413988d14ac8c68e4d42c8 ] Incorrect invocation of VMA callbacks when the VMA is no longer in a consistent state is bug prone and risky to perform. With regards to the important vm_ops->close() callback We have gone to great lengths to try to track whether or not we ought to close VMAs. Rather than doing so and risking making a mistake somewhere, instead unconditionally close and reset vma->vm_ops to an empty dummy operations set with a NULL .close operator. We introduce a new function to do so - vma_close() - and simplify existing vms logic which tracked whether we needed to close or not. This simplifies the logic, avoids incorrect double-calling of the .close() callback and allows us to update error paths to simply call vma_close() unconditionally - making VMA closure idempotent. Link: https://lkml.kernel.org/r/28e89dda96f68c505cb6f8e9fc9b57c3e9f74b42.173022466... Fixes: deb0f6562884 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails") Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reported-by: Jann Horn <jannh@google.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reviewed-by: Jann Horn <jannh@google.com> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Helge Deller <deller@gmx.de> Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Brown <broonie@kernel.org> Cc: Peter Xu <peterx@redhat.com> Cc: Will Deacon <will@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ma Wupeng <mawupeng1@huawei.com> --- mm/internal.h | 7 +++++++ mm/mmap.c | 9 +++------ mm/nommu.c | 3 +-- mm/util.c | 15 +++++++++++++++ 4 files changed, 26 insertions(+), 8 deletions(-) diff --git a/mm/internal.h b/mm/internal.h index 6897a119a383..0f49e0e7a0aa 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -61,6 +61,13 @@ void page_writeback_init(void); */ int mmap_file(struct file *file, struct vm_area_struct *vma); +/* + * If the VMA has a close hook then close it, and since closing it might leave + * it in an inconsistent state which makes the use of any hooks suspect, clear + * them down by installing dummy empty hooks. + */ +void vma_close(struct vm_area_struct *vma); + vm_fault_t do_swap_page(struct vm_fault *vmf); void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma, diff --git a/mm/mmap.c b/mm/mmap.c index d4e1099be6e0..3a1f685bff50 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -185,8 +185,7 @@ static struct vm_area_struct *remove_vma(struct vm_area_struct *vma) struct vm_area_struct *next = vma->vm_next; might_sleep(); - if (vma->vm_ops && vma->vm_ops->close) - vma->vm_ops->close(vma); + vma_close(vma); if (vma->vm_file) fput(vma->vm_file); mpol_put(vma_policy(vma)); @@ -1959,8 +1958,7 @@ static unsigned long __mmap_region(struct mm_struct *mm, struct file *file, return addr; close_and_free_vma: - if (vma->vm_ops && vma->vm_ops->close) - vma->vm_ops->close(vma); + vma_close(vma); unmap_and_free_vma: vma->vm_file = NULL; fput(file); @@ -2885,8 +2883,7 @@ int __split_vma(struct mm_struct *mm, struct vm_area_struct *vma, return 0; /* Clean everything up if vma_adjust failed. */ - if (new->vm_ops && new->vm_ops->close) - new->vm_ops->close(new); + vma_close(new); if (new->vm_file) fput(new->vm_file); unlink_anon_vmas(new); diff --git a/mm/nommu.c b/mm/nommu.c index fdacc3d119c3..f46a883e93e4 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -662,8 +662,7 @@ static void delete_vma_from_mm(struct vm_area_struct *vma) */ static void delete_vma(struct mm_struct *mm, struct vm_area_struct *vma) { - if (vma->vm_ops && vma->vm_ops->close) - vma->vm_ops->close(vma); + vma_close(vma); if (vma->vm_file) fput(vma->vm_file); put_nommu_region(vma->vm_region); diff --git a/mm/util.c b/mm/util.c index 154335493dee..072c0251f652 100644 --- a/mm/util.c +++ b/mm/util.c @@ -1097,3 +1097,18 @@ int mmap_file(struct file *file, struct vm_area_struct *vma) return err; } + +void vma_close(struct vm_area_struct *vma) +{ + static const struct vm_operations_struct dummy_vm_ops = {}; + + if (vma->vm_ops && vma->vm_ops->close) { + vma->vm_ops->close(vma); + + /* + * The mapping is in an inconsistent state, and no further hooks + * may be invoked upon it. + */ + vma->vm_ops = &dummy_vm_ops; + } +} -- 2.43.0