Messages in this thread | | | Date | Wed, 24 Aug 2022 16:00:54 +0200 | Subject | Re: [POSSIBLE BUG] Dereferencing of NULL pointer | From | Juergen Gross <> |
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On 24.08.22 15:59, Jan Beulich wrote: > On 20.08.2022 19:30, Rustam Subkhankulov wrote: >> Version: 6.0-rc1 >> >> Description: >> >> In function 'privcmd_ioctl_dm_op' (drivers/xen/privcmd.c: 615)return >> value of 'kcalloc' with GFP_KERNEL flag is assigned to "pages" >> variable. GFP_KERNEL flag does not guarantee, that the return value >> will not be NULL. In that case, there is a jump to the "out" label. > > The problem is wider than that, because earlier errors would also > lead to "out" (e.g. after copy_from_user() failed). Plus I guess > unlock_pages() shouldn't be called at all (or with its 2nd arg set > to zero) before lock_pages() was actually called. But I agree with > the further analysis below. Would you mind sending a patch?
Just started writing it. :-)
Juergen [unhandled content-type:application/pgp-keys][unhandled content-type:application/pgp-signature] | |