Re: [PATCH v2] net: fix NULL pointer reference in cipso_v4_doi_free
From: Paul Moore <paul@paul-moore.com>
Date: 2021-08-30 16:50:48
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lkml, netdev
On Mon, Aug 30, 2021 at 12:45 PM Jakub Kicinski [off-list ref] wrote:
On Mon, 30 Aug 2021 10:17:05 -0400 Paul Moore wrote:quoted
On Mon, Aug 30, 2021 at 6:28 AM 王贇 [off-list ref] wrote:quoted
In netlbl_cipsov4_add_std() when 'doi_def->map.std' alloc failed, we sometime observe panic: BUG: kernel NULL pointer dereference, address: ... RIP: 0010:cipso_v4_doi_free+0x3a/0x80 ... Call Trace: netlbl_cipsov4_add_std+0xf4/0x8c0 netlbl_cipsov4_add+0x13f/0x1b0 genl_family_rcv_msg_doit.isra.15+0x132/0x170 genl_rcv_msg+0x125/0x240 This is because in cipso_v4_doi_free() there is no check on 'doi_def->map.std' when doi_def->type got value 1, which is possibe, since netlbl_cipsov4_add_std() haven't initialize it before alloc 'doi_def->map.std'. This patch just add the check to prevent panic happen in similar cases. Reported-by: Abaci <redacted> Signed-off-by: Michael Wang <redacted> --- net/netlabel/netlabel_cipso_v4.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)I see this was already merged, but it looks good to me, thanks for making those changes.FWIW it looks like v1 was also merged: https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git/commit/?id=733c99ee8b
Yeah, that is unfortunate, there was a brief discussion about that over on one of the -stable patches for the v1 patch (odd that I never saw a patchbot post for the v1 patch?). Having both merged should be harmless, but we want to revert the v1 patch as soon as we can. Michael, can you take care of this? -- paul moore www.paul-moore.com