On Tue, 2017-11-14 at 16:47 +0300, Vitaly Lipatov wrote: > for fcntl64 with F_GETLK64 we need use checking against COMPAT_LOFF_T_MAX. > > Fixes: 94073ad77fff2 "fs/locks: don't mess with the address limit in > compat_fcntl64" > > Signed-off-by: Vitaly Lipatov <[email protected]> > --- > fs/fcntl.c | 14 +++++++------- > 1 file changed, 7 insertions(+), 7 deletions(-) > > diff --git a/fs/fcntl.c b/fs/fcntl.c > index 30f47d0..e9443d9 100644 > --- a/fs/fcntl.c > +++ b/fs/fcntl.c > @@ -590,17 +590,17 @@ convert_fcntl_cmd(unsigned int cmd) > * GETLK was successful and we need to return the data, but it needs to fit > in > * the compat structure. > * l_start shouldn't be too big, unless the original start + end is greater > than > - * COMPAT_OFF_T_MAX, in which case the app was asking for trouble, so we > return > + * COMPAT_OFF_T_MAX/COMPAT_LOFF_T_MAX, in which case the app was asking for > trouble, so we return > * -EOVERFLOW in that case. l_len could be too big, in which case we just > * truncate it, and only allow the app to see that part of the conflicting > lock > * that might make sense to it anyway > */ > -static int fixup_compat_flock(struct flock *flock) > +static int fixup_compat_flock(struct flock *flock, loff_t off_t_max) > { > - if (flock->l_start > COMPAT_OFF_T_MAX) > + if (flock->l_start > off_t_max) > return -EOVERFLOW; > - if (flock->l_len > COMPAT_OFF_T_MAX) > - flock->l_len = COMPAT_OFF_T_MAX; > + if (flock->l_len > off_t_max) > + flock->l_len = off_t_max; > return 0; > } > > @@ -631,7 +631,7 @@ COMPAT_SYSCALL_DEFINE3(fcntl64, unsigned int, fd, > unsigned int, cmd, > err = fcntl_getlk(f.file, convert_fcntl_cmd(cmd), &flock); > if (err) > break; > - err = fixup_compat_flock(&flock); > + err = fixup_compat_flock(&flock, COMPAT_OFF_T_MAX); > if (err) > return err; > err = put_compat_flock(&flock, compat_ptr(arg)); > @@ -644,7 +644,7 @@ COMPAT_SYSCALL_DEFINE3(fcntl64, unsigned int, fd, > unsigned int, cmd, > err = fcntl_getlk(f.file, convert_fcntl_cmd(cmd), &flock); > if (err) > break; > - err = fixup_compat_flock(&flock); > + err = fixup_compat_flock(&flock, COMPAT_OFF_T_MAX);
I think you want COMPAT_LOFF_T_MAX here? In any case, I'm fine with the first version, and just renaming the function. I'll plan to push that one unless you have a reason that we should do it this way. > if (err) > return err; > err = put_compat_flock64(&flock, compat_ptr(arg)); Thanks, -- Jeff Layton <[email protected]>
