RE: [PATCHES] uaccess simple access_ok() removals
From: Al Viro > Sent: 10 May 2020 00:41 > > One of the uaccess-related branches; this one is just the > cases when access_ok() calls are trivially pointless - the address > in question gets fed only to primitives that do access_ok() checks > themselves. There is also the check in rw_copy_check_uvector() that should always be replicated by the copy_to/from_user() in _copy_to/from_iter(). And the strange call to rw_copy_check_uvector() in mm/process_vm_access.c which carefully avoids the access_ok() check for the target process. I did a quick look, but failed to see an obvious check further down the call path. The code is doing a read/write from another process, not sure when it is used - not by gdb. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
Re: [PATCHES] uaccess simple access_ok() removals
On Sat, May 09, 2020 at 05:34:58PM -0700, Linus Torvalds wrote: > On Sat, May 9, 2020 at 4:41 PM Al Viro wrote: > > > > Individual patches in followups; if nobody screams - into #for-next > > it goes... > > Looks fine to me, although I only read your commit logs, I didn't > verify that what you stated was actually true (ie the whole "only used > for xyz" parts). > > But I'll take your word for it. Particularly the double-underscore > versions are getting rare (and presumably some of the other branches > you have make it rarer still). I have - FWIW, right now I'm going through the patch series for netdev; once I'm done with turning commit messages into something printable (and finish rereading the patches themselves), there it goes, hopefully tonight. Then a bunch of small branches + repost of csum one + some of the weird shit (comedi compat ioctls - the largest pile of __get_user() and __put_user() outside of arch/* is festering there). Then regset stuff + (probably) resurrection of i915 stuff. I've got a bunch of stuff around execve(), but that'll have to wait until I get through the recently posted execve-related patchsets... Then there's e.g. mempolicy compat stuff, etc., but I'd rather wait for several days before posting that, reviewers' bandwidth being finite...
Re: [PATCHES] uaccess simple access_ok() removals
On Sat, May 9, 2020 at 4:41 PM Al Viro wrote: > > Individual patches in followups; if nobody screams - into #for-next > it goes... Looks fine to me, although I only read your commit logs, I didn't verify that what you stated was actually true (ie the whole "only used for xyz" parts). But I'll take your word for it. Particularly the double-underscore versions are getting rare (and presumably some of the other branches you have make it rarer still). Linus
[PATCHES] uaccess simple access_ok() removals
One of the uaccess-related branches; this one is just the cases when access_ok() calls are trivially pointless - the address in question gets fed only to primitives that do access_ok() checks themselves. This stuff sits in git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs.git #uaccess.access_ok and it's on top of #fixes (which is already merged into mainline on Apr 28). Individual patches in followups; if nobody screams - into #for-next it goes... There are other uaccess-related branches; I'll be posting them for review over the next few days. My apologies if this one comes with a buggered Cc - this is the first time I have to deal with a series with Cc lists varying that much; I hope I manage to get git-send-email do the right thing, but... Shortlog: Al Viro (20): dlmfs_file_write(): get rid of pointless access_ok() fat_dir_ioctl(): hadn't needed that access_ok() for more than a decade... btrfs_ioctl_send(): don't bother with access_ok() FIEMAP: don't bother with access_ok() tomoyo_write_control(): get rid of pointless access_ok() n_hdlc_tty_read(): remove pointless access_ok() nvram: drop useless access_ok() cm4000_cs.c cmm_ioctl(): get rid of pointless access_ok() drivers/fpga/dfl-fme-pr.c: get rid of pointless access_ok() drivers/fpga/dfl-afu-dma-region.c: get rid of pointless access_ok() amifb: get rid of pointless access_ok() calls omapfb: get rid of pointless access_ok() calls drivers/crypto/ccp/sev-dev.c: get rid of pointless access_ok() via-pmu: don't bother with access_ok() drm_read(): get rid of pointless access_ok() efi_test: get rid of pointless access_ok() lpfc_debugfs: get rid of pointless access_ok() usb: get rid of pointless access_ok() calls hfi1: get rid of pointless access_ok() vmci_host: get rid of pointless access_ok() Diffstat: drivers/char/nvram.c| 4 drivers/char/pcmcia/cm4000_cs.c | 14 -- drivers/crypto/ccp/sev-dev.c| 15 +++ drivers/firmware/efi/test/efi_test.c| 12 drivers/fpga/dfl-afu-dma-region.c | 4 drivers/fpga/dfl-fme-pr.c | 4 drivers/gpu/drm/drm_file.c | 3 --- drivers/infiniband/hw/hfi1/user_exp_rcv.c | 7 --- drivers/macintosh/via-pmu.c | 2 -- drivers/misc/vmw_vmci/vmci_host.c | 2 -- drivers/scsi/lpfc/lpfc_debugfs.c| 12 drivers/tty/n_hdlc.c| 7 --- drivers/usb/core/devices.c | 2 -- drivers/usb/core/devio.c| 9 - drivers/usb/gadget/function/f_hid.c | 6 -- drivers/video/fbdev/amifb.c | 4 drivers/video/fbdev/omap2/omapfb/omapfb-ioctl.c | 3 --- fs/btrfs/send.c | 7 --- fs/ext4/ioctl.c | 5 - fs/fat/dir.c| 4 fs/ioctl.c | 5 - fs/ocfs2/dlmfs/dlmfs.c | 3 --- security/tomoyo/common.c| 2 -- 23 files changed, 3 insertions(+), 133 deletions(-)
