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charset=us-ascii Content-Disposition: inline In-Reply-To: <8408d8901e9d7ee6b78db4c6cba04b78@ispras.ru> X-Rspamd-Queue-Id: 4B3EEA0014 X-Stat-Signature: eh9ihayji98nwuciintow85sez1jfgok X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1678279029-446790 X-HE-Meta: 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 cJ0jwuCO p9ZjMr4ZQ5lOFUjqHPX+pZZn49QQAL61JZWCB78iae6T2cJzbZAGYLSC+0cifYnFOG+uAAW/U/QUfqbW8O/ay6X8nfA0qq/83Tm0HVu+xmYulreAFMHsRW6y73wgzQJ1uea7cCkvbNnkSEjGyA/S16D7MdTPxDQVqwK1fn24ARmDcT/NH4E+TCvmU36fbC78DG2Ctcdr6wXkot5tcgWtw4RAmbF/JUWrajWvc90+bOeewtNpGiBP5nSn3LBIWCGVQixrQ7gziF5HYPFfVRw5+JKFU4+jwOPGvpqvBO4y/YSryhGFPFPb0m+Hump1WZxNHOWB7rr3CHDld91j2oWoOpGOot+KKsK0JK4R59SpnxbulokcIGd7cTVADD4o6o3ABgyaxczomhfNXKXREur4t6RQ1R9spCSQno7dVdoTEuE3hfRE/mkBKomH9FA== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Mar 07, 2023 at 04:01:56PM +0300, Alexey Izbyshev wrote: > On 2023-01-19 19:03, Joey Gouly wrote: > > diff --git a/mm/mmap.c b/mm/mmap.c > > index 87d929316d57..99a4d9e2b0d8 100644 > > --- a/mm/mmap.c > > +++ b/mm/mmap.c > > @@ -2665,6 +2665,16 @@ unsigned long mmap_region(struct file *file, > > unsigned long addr, > > vma_set_anonymous(vma); > > } > > > > + if (map_deny_write_exec(vma, vma->vm_flags)) { > > + error = -EACCES; > > + if (file) > > + goto close_and_free_vma; > > + else if (vma->vm_file) > > + goto unmap_and_free_vma; > > + else > > + goto free_vma; > > + } > > + > > Why is the cleanup dispatch logic duplicated here, instead of simply doing > "goto close_and_free_vma" (where basically the same dispatch is done)? Yes, though that's only possible after commit cc8d1b097de7 ("mmap: clean up mmap_region() unrolling") in 6.3-rc1. It's worth adding a separate patch to simplify this before final 6.3. > > diff --git a/mm/mprotect.c b/mm/mprotect.c > > index 908df12caa26..bc0587df042f 100644 > > --- a/mm/mprotect.c > > +++ b/mm/mprotect.c > > @@ -762,6 +762,11 @@ static int do_mprotect_pkey(unsigned long start, > > size_t len, > > break; > > } > > > > + if (map_deny_write_exec(vma, newflags)) { > > + error = -EACCES; > > + goto out; > > + } > > + > > Why does this check use "goto out", thereby skipping post-loop cleanup, > instead of "break" like all other checks? This looks like a bug to me. Ah, good point, thanks. I think that's a left-over from my early attempt at this series. The loop was changed in 5.19 with commit 4a18419f71cd ("mm/mprotect: use mmu_gather") but the patch not updated. So yeah, it needs fixing. Joey, could you please send fixes for both issues above? Thanks. -- Catalin