Message ID | 0-v1-d5b86dab17dc+28c25-ucma_syz_min_jgg@nvidia.com (mailing list archive) |
---|---|
State | Mainlined |
Commit | 31142a4ba617f5aa8aefdf1c65561ca30d43f360 |
Delegated to: | Jason Gunthorpe |
Headers | show |
Series | RDMA/cm: Add min length checks to user structure copies | expand |
On Fri, Jul 24, 2020 at 10:19:29AM -0300, Jason Gunthorpe wrote: > These are missing throughout ucma, it harmlessly copies garbage from > userspace, but in this new code which uses min to compute the copy length > it can result in uninitialized stack memory. Check for minimum length at > the very start. > > BUG: KMSAN: uninit-value in ucma_connect+0x2aa/0xab0 drivers/infiniband/core/ucma.c:1091 > CPU: 0 PID: 8457 Comm: syz-executor069 Not tainted 5.8.0-rc5-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:77 [inline] > dump_stack+0x1df/0x240 lib/dump_stack.c:118 > kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121 > __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215 > ucma_connect+0x2aa/0xab0 drivers/infiniband/core/ucma.c:1091 > ucma_write+0x5c5/0x630 drivers/infiniband/core/ucma.c:1764 > do_loop_readv_writev fs/read_write.c:737 [inline] > do_iter_write+0x710/0xdc0 fs/read_write.c:1020 > vfs_writev fs/read_write.c:1091 [inline] > do_writev+0x42d/0x8f0 fs/read_write.c:1134 > __do_sys_writev fs/read_write.c:1207 [inline] > __se_sys_writev+0x9b/0xb0 fs/read_write.c:1204 > __x64_sys_writev+0x4a/0x70 fs/read_write.c:1204 > do_syscall_64+0xb0/0x150 arch/x86/entry/common.c:386 > entry_SYSCALL_64_after_hwframe+0x44/0xa9 > > Fixes: 34e2ab57a911 ("RDMA/ucma: Extend ucma_connect to receive ECE parameters") > Fixes: 0cb15372a615 ("RDMA/cma: Connect ECE to rdma_accept") > Reported-by: syzbot+086ab5ca9eafd2379aa6@syzkaller.appspotmail.com > Reported-by: syzbot+7446526858b83c8828b2@syzkaller.appspotmail.com > Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> > --- > drivers/infiniband/core/ucma.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c > index 5b87eee8ccc8b6..d03dacaef78805 100644 > --- a/drivers/infiniband/core/ucma.c > +++ b/drivers/infiniband/core/ucma.c > @@ -1084,6 +1084,8 @@ static ssize_t ucma_connect(struct ucma_file *file, const char __user *inbuf, > size_t in_size; > int ret; > > + if (in_len < offsetofend(typeof(cmd), reserved)) > + return -EINVAL; This check wasn't before the patches citied in Fixes lines. This is why I didn't add them while extended ucma_*. > in_size = min_t(size_t, in_len, sizeof(cmd)); > if (copy_from_user(&cmd, inbuf, in_size)) > return -EFAULT; > @@ -1141,6 +1143,8 @@ static ssize_t ucma_accept(struct ucma_file *file, const char __user *inbuf, > size_t in_size; > int ret; > > + if (in_len < offsetofend(typeof(cmd), reserved)) > + return -EINVAL; > in_size = min_t(size_t, in_len, sizeof(cmd)); > if (copy_from_user(&cmd, inbuf, in_size)) > return -EFAULT; > -- > 2.27.0 >
On Fri, Jul 24, 2020 at 04:45:45PM +0300, Leon Romanovsky wrote: > On Fri, Jul 24, 2020 at 10:19:29AM -0300, Jason Gunthorpe wrote: > > These are missing throughout ucma, it harmlessly copies garbage from > > userspace, but in this new code which uses min to compute the copy length > > it can result in uninitialized stack memory. Check for minimum length at > > the very start. > > > > BUG: KMSAN: uninit-value in ucma_connect+0x2aa/0xab0 drivers/infiniband/core/ucma.c:1091 > > CPU: 0 PID: 8457 Comm: syz-executor069 Not tainted 5.8.0-rc5-syzkaller #0 > > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > > Call Trace: > > __dump_stack lib/dump_stack.c:77 [inline] > > dump_stack+0x1df/0x240 lib/dump_stack.c:118 > > kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121 > > __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215 > > ucma_connect+0x2aa/0xab0 drivers/infiniband/core/ucma.c:1091 > > ucma_write+0x5c5/0x630 drivers/infiniband/core/ucma.c:1764 > > do_loop_readv_writev fs/read_write.c:737 [inline] > > do_iter_write+0x710/0xdc0 fs/read_write.c:1020 > > vfs_writev fs/read_write.c:1091 [inline] > > do_writev+0x42d/0x8f0 fs/read_write.c:1134 > > __do_sys_writev fs/read_write.c:1207 [inline] > > __se_sys_writev+0x9b/0xb0 fs/read_write.c:1204 > > __x64_sys_writev+0x4a/0x70 fs/read_write.c:1204 > > do_syscall_64+0xb0/0x150 arch/x86/entry/common.c:386 > > entry_SYSCALL_64_after_hwframe+0x44/0xa9 > > > > Fixes: 34e2ab57a911 ("RDMA/ucma: Extend ucma_connect to receive ECE parameters") > > Fixes: 0cb15372a615 ("RDMA/cma: Connect ECE to rdma_accept") > > Reported-by: syzbot+086ab5ca9eafd2379aa6@syzkaller.appspotmail.com > > Reported-by: syzbot+7446526858b83c8828b2@syzkaller.appspotmail.com > > Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> > > drivers/infiniband/core/ucma.c | 4 ++++ > > 1 file changed, 4 insertions(+) > > > > diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c > > index 5b87eee8ccc8b6..d03dacaef78805 100644 > > +++ b/drivers/infiniband/core/ucma.c > > @@ -1084,6 +1084,8 @@ static ssize_t ucma_connect(struct ucma_file *file, const char __user *inbuf, > > size_t in_size; > > int ret; > > > > + if (in_len < offsetofend(typeof(cmd), reserved)) > > + return -EINVAL; > > This check wasn't before the patches citied in Fixes lines. This is why > I didn't add them while extended ucma_*. It wasn't a bug before. > > in_size = min_t(size_t, in_len, sizeof(cmd)); > > if (copy_from_user(&cmd, inbuf, in_size)) > > return -EFAULT; Because this used to be: if (copy_from_user(&cmd, inbuf, sizeof(cmd))) Which always completely filled the stack memory. Jason
On Fri, Jul 24, 2020 at 10:52:44AM -0300, Jason Gunthorpe wrote: > On Fri, Jul 24, 2020 at 04:45:45PM +0300, Leon Romanovsky wrote: > > On Fri, Jul 24, 2020 at 10:19:29AM -0300, Jason Gunthorpe wrote: > > > These are missing throughout ucma, it harmlessly copies garbage from > > > userspace, but in this new code which uses min to compute the copy length > > > it can result in uninitialized stack memory. Check for minimum length at > > > the very start. > > > > > > BUG: KMSAN: uninit-value in ucma_connect+0x2aa/0xab0 drivers/infiniband/core/ucma.c:1091 > > > CPU: 0 PID: 8457 Comm: syz-executor069 Not tainted 5.8.0-rc5-syzkaller #0 > > > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > > > Call Trace: > > > __dump_stack lib/dump_stack.c:77 [inline] > > > dump_stack+0x1df/0x240 lib/dump_stack.c:118 > > > kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121 > > > __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215 > > > ucma_connect+0x2aa/0xab0 drivers/infiniband/core/ucma.c:1091 > > > ucma_write+0x5c5/0x630 drivers/infiniband/core/ucma.c:1764 > > > do_loop_readv_writev fs/read_write.c:737 [inline] > > > do_iter_write+0x710/0xdc0 fs/read_write.c:1020 > > > vfs_writev fs/read_write.c:1091 [inline] > > > do_writev+0x42d/0x8f0 fs/read_write.c:1134 > > > __do_sys_writev fs/read_write.c:1207 [inline] > > > __se_sys_writev+0x9b/0xb0 fs/read_write.c:1204 > > > __x64_sys_writev+0x4a/0x70 fs/read_write.c:1204 > > > do_syscall_64+0xb0/0x150 arch/x86/entry/common.c:386 > > > entry_SYSCALL_64_after_hwframe+0x44/0xa9 > > > > > > Fixes: 34e2ab57a911 ("RDMA/ucma: Extend ucma_connect to receive ECE parameters") > > > Fixes: 0cb15372a615 ("RDMA/cma: Connect ECE to rdma_accept") > > > Reported-by: syzbot+086ab5ca9eafd2379aa6@syzkaller.appspotmail.com > > > Reported-by: syzbot+7446526858b83c8828b2@syzkaller.appspotmail.com > > > Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> > > > drivers/infiniband/core/ucma.c | 4 ++++ > > > 1 file changed, 4 insertions(+) > > > > > > diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c > > > index 5b87eee8ccc8b6..d03dacaef78805 100644 > > > +++ b/drivers/infiniband/core/ucma.c > > > @@ -1084,6 +1084,8 @@ static ssize_t ucma_connect(struct ucma_file *file, const char __user *inbuf, > > > size_t in_size; > > > int ret; > > > > > > + if (in_len < offsetofend(typeof(cmd), reserved)) > > > + return -EINVAL; > > > > This check wasn't before the patches citied in Fixes lines. This is why > > I didn't add them while extended ucma_*. > > It wasn't a bug before. > > > > in_size = min_t(size_t, in_len, sizeof(cmd)); > > > if (copy_from_user(&cmd, inbuf, in_size)) > > > return -EFAULT; > > Because this used to be: > > if (copy_from_user(&cmd, inbuf, sizeof(cmd))) > > Which always completely filled the stack memory. I see, thanks. > > Jason
On Fri, Jul 24, 2020 at 10:19:29AM -0300, Jason Gunthorpe wrote: > These are missing throughout ucma, it harmlessly copies garbage from > userspace, but in this new code which uses min to compute the copy length > it can result in uninitialized stack memory. Check for minimum length at > the very start. > > BUG: KMSAN: uninit-value in ucma_connect+0x2aa/0xab0 drivers/infiniband/core/ucma.c:1091 > CPU: 0 PID: 8457 Comm: syz-executor069 Not tainted 5.8.0-rc5-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:77 [inline] > dump_stack+0x1df/0x240 lib/dump_stack.c:118 > kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121 > __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215 > ucma_connect+0x2aa/0xab0 drivers/infiniband/core/ucma.c:1091 > ucma_write+0x5c5/0x630 drivers/infiniband/core/ucma.c:1764 > do_loop_readv_writev fs/read_write.c:737 [inline] > do_iter_write+0x710/0xdc0 fs/read_write.c:1020 > vfs_writev fs/read_write.c:1091 [inline] > do_writev+0x42d/0x8f0 fs/read_write.c:1134 > __do_sys_writev fs/read_write.c:1207 [inline] > __se_sys_writev+0x9b/0xb0 fs/read_write.c:1204 > __x64_sys_writev+0x4a/0x70 fs/read_write.c:1204 > do_syscall_64+0xb0/0x150 arch/x86/entry/common.c:386 > entry_SYSCALL_64_after_hwframe+0x44/0xa9 > > Fixes: 34e2ab57a911 ("RDMA/ucma: Extend ucma_connect to receive ECE parameters") > Fixes: 0cb15372a615 ("RDMA/cma: Connect ECE to rdma_accept") > Reported-by: syzbot+086ab5ca9eafd2379aa6@syzkaller.appspotmail.com > Reported-by: syzbot+7446526858b83c8828b2@syzkaller.appspotmail.com > Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> > --- > drivers/infiniband/core/ucma.c | 4 ++++ > 1 file changed, 4 insertions(+) > Thanks, Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
On Fri, Jul 24, 2020 at 10:19:29AM -0300, Jason Gunthorpe wrote: > These are missing throughout ucma, it harmlessly copies garbage from > userspace, but in this new code which uses min to compute the copy length > it can result in uninitialized stack memory. Check for minimum length at > the very start. > > BUG: KMSAN: uninit-value in ucma_connect+0x2aa/0xab0 drivers/infiniband/core/ucma.c:1091 > CPU: 0 PID: 8457 Comm: syz-executor069 Not tainted 5.8.0-rc5-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:77 [inline] > dump_stack+0x1df/0x240 lib/dump_stack.c:118 > kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121 > __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215 > ucma_connect+0x2aa/0xab0 drivers/infiniband/core/ucma.c:1091 > ucma_write+0x5c5/0x630 drivers/infiniband/core/ucma.c:1764 > do_loop_readv_writev fs/read_write.c:737 [inline] > do_iter_write+0x710/0xdc0 fs/read_write.c:1020 > vfs_writev fs/read_write.c:1091 [inline] > do_writev+0x42d/0x8f0 fs/read_write.c:1134 > __do_sys_writev fs/read_write.c:1207 [inline] > __se_sys_writev+0x9b/0xb0 fs/read_write.c:1204 > __x64_sys_writev+0x4a/0x70 fs/read_write.c:1204 > do_syscall_64+0xb0/0x150 arch/x86/entry/common.c:386 > entry_SYSCALL_64_after_hwframe+0x44/0xa9 > > Fixes: 34e2ab57a911 ("RDMA/ucma: Extend ucma_connect to receive ECE parameters") > Fixes: 0cb15372a615 ("RDMA/cma: Connect ECE to rdma_accept") > Reported-by: syzbot+086ab5ca9eafd2379aa6@syzkaller.appspotmail.com > Reported-by: syzbot+7446526858b83c8828b2@syzkaller.appspotmail.com > Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> > Reviewed-by: Leon Romanovsky <leonro@mellanox.com> > --- > drivers/infiniband/core/ucma.c | 4 ++++ > 1 file changed, 4 insertions(+) Applied to for-rc Jason
diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c index 5b87eee8ccc8b6..d03dacaef78805 100644 --- a/drivers/infiniband/core/ucma.c +++ b/drivers/infiniband/core/ucma.c @@ -1084,6 +1084,8 @@ static ssize_t ucma_connect(struct ucma_file *file, const char __user *inbuf, size_t in_size; int ret; + if (in_len < offsetofend(typeof(cmd), reserved)) + return -EINVAL; in_size = min_t(size_t, in_len, sizeof(cmd)); if (copy_from_user(&cmd, inbuf, in_size)) return -EFAULT; @@ -1141,6 +1143,8 @@ static ssize_t ucma_accept(struct ucma_file *file, const char __user *inbuf, size_t in_size; int ret; + if (in_len < offsetofend(typeof(cmd), reserved)) + return -EINVAL; in_size = min_t(size_t, in_len, sizeof(cmd)); if (copy_from_user(&cmd, inbuf, in_size)) return -EFAULT;
These are missing throughout ucma, it harmlessly copies garbage from userspace, but in this new code which uses min to compute the copy length it can result in uninitialized stack memory. Check for minimum length at the very start. BUG: KMSAN: uninit-value in ucma_connect+0x2aa/0xab0 drivers/infiniband/core/ucma.c:1091 CPU: 0 PID: 8457 Comm: syz-executor069 Not tainted 5.8.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1df/0x240 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215 ucma_connect+0x2aa/0xab0 drivers/infiniband/core/ucma.c:1091 ucma_write+0x5c5/0x630 drivers/infiniband/core/ucma.c:1764 do_loop_readv_writev fs/read_write.c:737 [inline] do_iter_write+0x710/0xdc0 fs/read_write.c:1020 vfs_writev fs/read_write.c:1091 [inline] do_writev+0x42d/0x8f0 fs/read_write.c:1134 __do_sys_writev fs/read_write.c:1207 [inline] __se_sys_writev+0x9b/0xb0 fs/read_write.c:1204 __x64_sys_writev+0x4a/0x70 fs/read_write.c:1204 do_syscall_64+0xb0/0x150 arch/x86/entry/common.c:386 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 34e2ab57a911 ("RDMA/ucma: Extend ucma_connect to receive ECE parameters") Fixes: 0cb15372a615 ("RDMA/cma: Connect ECE to rdma_accept") Reported-by: syzbot+086ab5ca9eafd2379aa6@syzkaller.appspotmail.com Reported-by: syzbot+7446526858b83c8828b2@syzkaller.appspotmail.com Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> --- drivers/infiniband/core/ucma.c | 4 ++++ 1 file changed, 4 insertions(+)