When the loop over the VMA is terminated early due to an error, the return code could be overwritten with ENOMEM. Fix the return code by only setting the error on early loop termination when the error is not set.
Fixes: 2286a6914c77 ("mm: change mprotect_fixup to vma iterator") Cc: stable@vger.kernel.org Signed-off-by: Liam R. Howlett Liam.Howlett@oracle.com --- mm/mprotect.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/mprotect.c b/mm/mprotect.c index 13e84d8c0797..36351a00c0e8 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -838,7 +838,7 @@ static int do_mprotect_pkey(unsigned long start, size_t len, } tlb_finish_mmu(&tlb);
- if (vma_iter_end(&vmi) < end) + if (!error && vma_iter_end(&vmi) < end) error = -ENOMEM;
out:
On Thu, 6 Apr 2023 15:30:50 -0400 "Liam R. Howlett" Liam.Howlett@oracle.com wrote:
When the loop over the VMA is terminated early due to an error, the return code could be overwritten with ENOMEM. Fix the return code by only setting the error on early loop termination when the error is not set.
Fixes: 2286a6914c77 ("mm: change mprotect_fixup to vma iterator") Cc: stable@vger.kernel.org
I do think we should always describe the user-visible effects when proposing a backport.
a) so the -stable maintainers understand why we're recommending the backport and
b) to help some poor soul who is looking at the patch wondering if it will fix his customer's bug report.
How's this?
: User-visible effects include: attempts to run mprotect() against a special : mapping or with a poorly-aligned hugetlb address should return -EINVAL, : but they presently return -ENOMEM.
* Andrew Morton akpm@linux-foundation.org [230406 17:53]:
On Thu, 6 Apr 2023 15:30:50 -0400 "Liam R. Howlett" Liam.Howlett@oracle.com wrote:
When the loop over the VMA is terminated early due to an error, the return code could be overwritten with ENOMEM. Fix the return code by only setting the error on early loop termination when the error is not set.
Fixes: 2286a6914c77 ("mm: change mprotect_fixup to vma iterator") Cc: stable@vger.kernel.org
I do think we should always describe the user-visible effects when proposing a backport.
a) so the -stable maintainers understand why we're recommending the backport and
b) to help some poor soul who is looking at the patch wondering if it will fix his customer's bug report.
Thanks, I'll keep this in mind.
How's this?
: User-visible effects include: attempts to run mprotect() against a special : mapping or with a poorly-aligned hugetlb address should return -EINVAL, : but they presently return -ENOMEM.
That sounds reasonable, although this isn't an exhaustive list. It could be an -EACCESS for multiple reasons, or anything the vm_ops returns.
linux-stable-mirror@lists.linaro.org
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Andrew Morton -
Liam R. Howlett -
Liam R. Howlett