diff options
| author | Jens Axboe | 2020-10-26 18:03:18 -0600 |
|---|---|---|
| committer | Linus Torvalds | 2020-10-27 09:57:46 -0700 |
| commit | 38dc5079da7081e8b09b14e255e9da82c451a531 (patch) | |
| tree | f1c872f5a3cad39a3ac3d69766f3ccb0b56916f0 /mm | |
| parent | 4525c8781ec0701ce824e8bd379ae1b129e26568 (diff) | |
Fix compat regression in process_vm_rw()
The removal of compat_process_vm_{readv,writev} didn't change
process_vm_rw(), which always assumes it's not doing a compat syscall.
Instead of passing in 'false' unconditionally for 'compat', make it
conditional on in_compat_syscall().
[ Both Al and Christoph point out that trying to access a 64-bit process
from a 32-bit one cannot work anyway, and is likely better prohibited,
but that's a separate issue - Linus ]
Fixes: c3973b401ef2 ("mm: remove compat_process_vm_{readv,writev}")
Reported-and-tested-by: Kyle Huey <me@kylehuey.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/process_vm_access.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/mm/process_vm_access.c b/mm/process_vm_access.c index fd12da80b6f2..05676722d9cd 100644 --- a/mm/process_vm_access.c +++ b/mm/process_vm_access.c @@ -273,7 +273,8 @@ static ssize_t process_vm_rw(pid_t pid, return rc; if (!iov_iter_count(&iter)) goto free_iov_l; - iov_r = iovec_from_user(rvec, riovcnt, UIO_FASTIOV, iovstack_r, false); + iov_r = iovec_from_user(rvec, riovcnt, UIO_FASTIOV, iovstack_r, + in_compat_syscall()); if (IS_ERR(iov_r)) { rc = PTR_ERR(iov_r); goto free_iov_l; |