diff mbox series

[v4] net/qrtr: fix __netdev_alloc_skb call

Message ID 20210228232240.972205-1-paskripkin@gmail.com (mailing list archive)
State Accepted
Commit 093b036aa94e01a0bea31a38d7f0ee28a2749023
Delegated to: Netdev Maintainers
Headers show
Series [v4] net/qrtr: fix __netdev_alloc_skb call | expand

Checks

Context Check Description
netdev/cover_letter success Link
netdev/fixes_present success Link
netdev/patch_count success Link
netdev/tree_selection success Guessed tree name to be net-next
netdev/subject_prefix warning Target tree name not specified in the subject
netdev/cc_maintainers warning 10 maintainers not CCed: dan.carpenter@oracle.com mani@kernel.org kuba@kernel.org davem@davemloft.net necip@google.com bjorn.andersson@linaro.org cjhuang@codeaurora.org loic.poulain@linaro.org miaoqinglang@huawei.com edumazet@google.com
netdev/source_inline success Was 0 now: 0
netdev/verify_signedoff success Link
netdev/module_param success Was 0 now: 0
netdev/build_32bit success Errors and warnings before: 3 this patch: 3
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/verify_fixes success Link
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 8 lines checked
netdev/build_allmodconfig_warn success Errors and warnings before: 3 this patch: 3
netdev/header_inline success Link
netdev/stable success Stable not CCed

Commit Message

Pavel Skripkin Feb. 28, 2021, 11:22 p.m. UTC
syzbot found WARNING in __alloc_pages_nodemask()[1] when order >= MAX_ORDER.
It was caused by a huge length value passed from userspace to qrtr_tun_write_iter(),
which tries to allocate skb. Since the value comes from the untrusted source 
there is no need to raise a warning in __alloc_pages_nodemask().

[1] WARNING in __alloc_pages_nodemask+0x5f8/0x730 mm/page_alloc.c:5014
Call Trace:
 __alloc_pages include/linux/gfp.h:511 [inline]
 __alloc_pages_node include/linux/gfp.h:524 [inline]
 alloc_pages_node include/linux/gfp.h:538 [inline]
 kmalloc_large_node+0x60/0x110 mm/slub.c:3999
 __kmalloc_node_track_caller+0x319/0x3f0 mm/slub.c:4496
 __kmalloc_reserve net/core/skbuff.c:150 [inline]
 __alloc_skb+0x4e4/0x5a0 net/core/skbuff.c:210
 __netdev_alloc_skb+0x70/0x400 net/core/skbuff.c:446
 netdev_alloc_skb include/linux/skbuff.h:2832 [inline]
 qrtr_endpoint_post+0x84/0x11b0 net/qrtr/qrtr.c:442
 qrtr_tun_write_iter+0x11f/0x1a0 net/qrtr/tun.c:98
 call_write_iter include/linux/fs.h:1901 [inline]
 new_sync_write+0x426/0x650 fs/read_write.c:518
 vfs_write+0x791/0xa30 fs/read_write.c:605
 ksys_write+0x12d/0x250 fs/read_write.c:658
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported-by: syzbot+80dccaee7c6630fa9dcf@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
---
 net/qrtr/qrtr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Alexander Lobakin Feb. 28, 2021, 11:53 p.m. UTC | #1
From: Pavel Skripkin <paskripkin@gmail.com>
Date: Mon, 1 Mar 2021 02:22:40 +0300

> syzbot found WARNING in __alloc_pages_nodemask()[1] when order >= MAX_ORDER.
> It was caused by a huge length value passed from userspace to qrtr_tun_write_iter(),
> which tries to allocate skb. Since the value comes from the untrusted source
> there is no need to raise a warning in __alloc_pages_nodemask().
>
> [1] WARNING in __alloc_pages_nodemask+0x5f8/0x730 mm/page_alloc.c:5014
> Call Trace:
>  __alloc_pages include/linux/gfp.h:511 [inline]
>  __alloc_pages_node include/linux/gfp.h:524 [inline]
>  alloc_pages_node include/linux/gfp.h:538 [inline]
>  kmalloc_large_node+0x60/0x110 mm/slub.c:3999
>  __kmalloc_node_track_caller+0x319/0x3f0 mm/slub.c:4496
>  __kmalloc_reserve net/core/skbuff.c:150 [inline]
>  __alloc_skb+0x4e4/0x5a0 net/core/skbuff.c:210
>  __netdev_alloc_skb+0x70/0x400 net/core/skbuff.c:446
>  netdev_alloc_skb include/linux/skbuff.h:2832 [inline]
>  qrtr_endpoint_post+0x84/0x11b0 net/qrtr/qrtr.c:442
>  qrtr_tun_write_iter+0x11f/0x1a0 net/qrtr/tun.c:98
>  call_write_iter include/linux/fs.h:1901 [inline]
>  new_sync_write+0x426/0x650 fs/read_write.c:518
>  vfs_write+0x791/0xa30 fs/read_write.c:605
>  ksys_write+0x12d/0x250 fs/read_write.c:658
>  do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
>  entry_SYSCALL_64_after_hwframe+0x44/0xa9
>
> Reported-by: syzbot+80dccaee7c6630fa9dcf@syzkaller.appspotmail.com
> Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>

Acked-by: Alexander Lobakin <alobakin@pm.me>

Thanks!

> ---
>  net/qrtr/qrtr.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/net/qrtr/qrtr.c b/net/qrtr/qrtr.c
> index b34358282f37..82d2eb8c21d1 100644
> --- a/net/qrtr/qrtr.c
> +++ b/net/qrtr/qrtr.c
> @@ -439,7 +439,7 @@ int qrtr_endpoint_post(struct qrtr_endpoint *ep, const void *data, size_t len)
>  	if (len == 0 || len & 3)
>  		return -EINVAL;
>
> -	skb = netdev_alloc_skb(NULL, len);
> +	skb = __netdev_alloc_skb(NULL, len, GFP_ATOMIC | __GFP_NOWARN);
>  	if (!skb)
>  		return -ENOMEM;
>
> --
> 2.25.1

Al
patchwork-bot+netdevbpf@kernel.org March 1, 2021, 9:30 p.m. UTC | #2
Hello:

This patch was applied to netdev/net.git (refs/heads/master):

On Mon,  1 Mar 2021 02:22:40 +0300 you wrote:
> syzbot found WARNING in __alloc_pages_nodemask()[1] when order >= MAX_ORDER.
> It was caused by a huge length value passed from userspace to qrtr_tun_write_iter(),
> which tries to allocate skb. Since the value comes from the untrusted source
> there is no need to raise a warning in __alloc_pages_nodemask().
> 
> [1] WARNING in __alloc_pages_nodemask+0x5f8/0x730 mm/page_alloc.c:5014
> Call Trace:
>  __alloc_pages include/linux/gfp.h:511 [inline]
>  __alloc_pages_node include/linux/gfp.h:524 [inline]
>  alloc_pages_node include/linux/gfp.h:538 [inline]
>  kmalloc_large_node+0x60/0x110 mm/slub.c:3999
>  __kmalloc_node_track_caller+0x319/0x3f0 mm/slub.c:4496
>  __kmalloc_reserve net/core/skbuff.c:150 [inline]
>  __alloc_skb+0x4e4/0x5a0 net/core/skbuff.c:210
>  __netdev_alloc_skb+0x70/0x400 net/core/skbuff.c:446
>  netdev_alloc_skb include/linux/skbuff.h:2832 [inline]
>  qrtr_endpoint_post+0x84/0x11b0 net/qrtr/qrtr.c:442
>  qrtr_tun_write_iter+0x11f/0x1a0 net/qrtr/tun.c:98
>  call_write_iter include/linux/fs.h:1901 [inline]
>  new_sync_write+0x426/0x650 fs/read_write.c:518
>  vfs_write+0x791/0xa30 fs/read_write.c:605
>  ksys_write+0x12d/0x250 fs/read_write.c:658
>  do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
>  entry_SYSCALL_64_after_hwframe+0x44/0xa9
> 
> [...]

Here is the summary with links:
  - [v4] net/qrtr: fix __netdev_alloc_skb call
    https://git.kernel.org/netdev/net/c/093b036aa94e

You are awesome, thank you!
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diff mbox series

Patch

diff --git a/net/qrtr/qrtr.c b/net/qrtr/qrtr.c
index b34358282f37..82d2eb8c21d1 100644
--- a/net/qrtr/qrtr.c
+++ b/net/qrtr/qrtr.c
@@ -439,7 +439,7 @@  int qrtr_endpoint_post(struct qrtr_endpoint *ep, const void *data, size_t len)
 	if (len == 0 || len & 3)
 		return -EINVAL;
 
-	skb = netdev_alloc_skb(NULL, len);
+	skb = __netdev_alloc_skb(NULL, len, GFP_ATOMIC | __GFP_NOWARN);
 	if (!skb)
 		return -ENOMEM;