The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x eebff19acaa35820cb09ce2ccb3d21bee2156ffb # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2023112205-eleven-enrich-934c@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
eebff19acaa3 ("ksmbd: fix slab out of bounds write in smb_inherit_dacl()")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From eebff19acaa35820cb09ce2ccb3d21bee2156ffb Mon Sep 17 00:00:00 2001 From: Namjae Jeon linkinjeon@kernel.org Date: Sun, 5 Nov 2023 12:46:24 +0900 Subject: [PATCH] ksmbd: fix slab out of bounds write in smb_inherit_dacl()
slab out-of-bounds write is caused by that offsets is bigger than pntsd allocation size. This patch add the check to validate 3 offsets using allocation size.
Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-22271 Cc: stable@vger.kernel.org Signed-off-by: Namjae Jeon linkinjeon@kernel.org Signed-off-by: Steve French stfrench@microsoft.com
diff --git a/fs/smb/server/smbacl.c b/fs/smb/server/smbacl.c index 6c0305be895e..51b8bfab7481 100644 --- a/fs/smb/server/smbacl.c +++ b/fs/smb/server/smbacl.c @@ -1107,6 +1107,7 @@ int smb_inherit_dacl(struct ksmbd_conn *conn, struct smb_acl *pdacl; struct smb_sid *powner_sid = NULL, *pgroup_sid = NULL; int powner_sid_size = 0, pgroup_sid_size = 0, pntsd_size; + int pntsd_alloc_size;
if (parent_pntsd->osidoffset) { powner_sid = (struct smb_sid *)((char *)parent_pntsd + @@ -1119,9 +1120,10 @@ int smb_inherit_dacl(struct ksmbd_conn *conn, pgroup_sid_size = 1 + 1 + 6 + (pgroup_sid->num_subauth * 4); }
- pntsd = kzalloc(sizeof(struct smb_ntsd) + powner_sid_size + - pgroup_sid_size + sizeof(struct smb_acl) + - nt_size, GFP_KERNEL); + pntsd_alloc_size = sizeof(struct smb_ntsd) + powner_sid_size + + pgroup_sid_size + sizeof(struct smb_acl) + nt_size; + + pntsd = kzalloc(pntsd_alloc_size, GFP_KERNEL); if (!pntsd) { rc = -ENOMEM; goto free_aces_base; @@ -1136,6 +1138,27 @@ int smb_inherit_dacl(struct ksmbd_conn *conn, pntsd->gsidoffset = parent_pntsd->gsidoffset; pntsd->dacloffset = parent_pntsd->dacloffset;
+ if ((u64)le32_to_cpu(pntsd->osidoffset) + powner_sid_size > + pntsd_alloc_size) { + rc = -EINVAL; + kfree(pntsd); + goto free_aces_base; + } + + if ((u64)le32_to_cpu(pntsd->gsidoffset) + pgroup_sid_size > + pntsd_alloc_size) { + rc = -EINVAL; + kfree(pntsd); + goto free_aces_base; + } + + if ((u64)le32_to_cpu(pntsd->dacloffset) + sizeof(struct smb_acl) + nt_size > + pntsd_alloc_size) { + rc = -EINVAL; + kfree(pntsd); + goto free_aces_base; + } + if (pntsd->osidoffset) { struct smb_sid *owner_sid = (struct smb_sid *)((char *)pntsd + le32_to_cpu(pntsd->osidoffset));