The hci_conn_unlink function is being called by hci_conn_del, which
means it should not call hci_conn_del with the input parameter conn
again. If it does, conn may have already been released when
hci_conn_unlink returns, leading to potential UAF and double-free
issues.
This patch resolves the problem by modifying hci_conn_unlink to release
only conn's child links when necessary, but never release conn itself.
Reported-by: [email protected]
Closes: https://lore.kernel.org/linux-bluetooth/[email protected]/
Fixes: 06149746e720 ("Bluetooth: hci_conn: Add support for linking multiple hcon")
Signed-off-by: Ruihan Li <[email protected]>
---
net/bluetooth/hci_conn.c | 21 ++++++++++++---------
1 file changed, 12 insertions(+), 9 deletions(-)
diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
index 640b951bf..70e1655a9 100644
--- a/net/bluetooth/hci_conn.c
+++ b/net/bluetooth/hci_conn.c
@@ -1083,8 +1083,18 @@ static void hci_conn_unlink(struct hci_conn *conn)
if (!conn->parent) {
struct hci_link *link, *t;
- list_for_each_entry_safe(link, t, &conn->link_list, list)
- hci_conn_unlink(link->conn);
+ list_for_each_entry_safe(link, t, &conn->link_list, list) {
+ struct hci_conn *child = link->conn;
+
+ hci_conn_unlink(child);
+
+ /* Due to race, SCO connection might be not established
+ * yet at this point. Delete it now, otherwise it is
+ * possible for it to be stuck and can't be deleted.
+ */
+ if (child->handle == HCI_CONN_HANDLE_UNSET)
+ hci_conn_del(child);
+ }
return;
}
@@ -1100,13 +1110,6 @@ static void hci_conn_unlink(struct hci_conn *conn)
kfree(conn->link);
conn->link = NULL;
-
- /* Due to race, SCO connection might be not established
- * yet at this point. Delete it now, otherwise it is
- * possible for it to be stuck and can't be deleted.
- */
- if (conn->handle == HCI_CONN_HANDLE_UNSET)
- hci_conn_del(conn);
}
int hci_conn_del(struct hci_conn *conn)
--
2.40.0
This is automated email and please do not reply to this email!
Dear submitter,
Thank you for submitting the patches to the linux bluetooth mailing list.
This is a CI test results with your patch series:
PW Link:https://patchwork.kernel.org/project/bluetooth/list/?series=744426
---Test result---
Test Summary:
CheckPatch FAIL 4.18 seconds
GitLint FAIL 2.05 seconds
SubjectPrefix PASS 0.60 seconds
BuildKernel PASS 32.22 seconds
CheckAllWarning PASS 35.05 seconds
CheckSparse PASS 39.69 seconds
CheckSmatch PASS 110.75 seconds
BuildKernel32 PASS 31.05 seconds
TestRunnerSetup PASS 440.47 seconds
TestRunner_l2cap-tester PASS 16.56 seconds
TestRunner_iso-tester PASS 20.35 seconds
TestRunner_bnep-tester PASS 5.36 seconds
TestRunner_mgmt-tester PASS 113.08 seconds
TestRunner_rfcomm-tester PASS 8.52 seconds
TestRunner_sco-tester PASS 7.90 seconds
TestRunner_ioctl-tester PASS 9.26 seconds
TestRunner_mesh-tester PASS 6.76 seconds
TestRunner_smp-tester PASS 7.93 seconds
TestRunner_userchan-tester PASS 5.61 seconds
IncrementalBuild PASS 75.99 seconds
Details
##############################
Test: CheckPatch - FAIL
Desc: Run checkpatch.pl script
Output:
[v3,1/6] Bluetooth: Fix potential double free caused by hci_conn_unlink
WARNING: Reported-by: should be immediately followed by Link: with a URL to the report
#83:
Reported-by: [email protected]
Closes: https://lore.kernel.org/linux-bluetooth/[email protected]/
WARNING: Possible unwrapped commit description (prefer a maximum 75 chars per line)
#84:
Closes: https://lore.kernel.org/linux-bluetooth/[email protected]/
WARNING: Unknown link reference 'Closes:', use 'Link:' instead
#84:
Closes: https://lore.kernel.org/linux-bluetooth/[email protected]/
total: 0 errors, 3 warnings, 0 checks, 33 lines checked
NOTE: For some of the reported defects, checkpatch may be able to
mechanically convert to the typical style using --fix or --fix-inplace.
/github/workspace/src/src/13229025.patch has style problems, please review.
NOTE: Ignored message types: UNKNOWN_COMMIT_ID
NOTE: If any of the errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.
[v3,2/6] Bluetooth: Refcnt drop must be placed last in hci_conn_unlink
WARNING: Reported-by: should be immediately followed by Link: with a URL to the report
#82:
Reported-by: Luiz Augusto von Dentz <[email protected]>
Closes: https://lore.kernel.org/linux-bluetooth/CABBYNZ+1kce8_RJrLNOXd_8=Mdpb=2bx4Nto-hFORk=qiOkoCg@mail.gmail.com/
WARNING: Possible unwrapped commit description (prefer a maximum 75 chars per line)
#83:
Closes: https://lore.kernel.org/linux-bluetooth/CABBYNZ+1kce8_RJrLNOXd_8=Mdpb=2bx4Nto-hFORk=qiOkoCg@mail.gmail.com/
WARNING: Unknown link reference 'Closes:', use 'Link:' instead
#83:
Closes: https://lore.kernel.org/linux-bluetooth/CABBYNZ+1kce8_RJrLNOXd_8=Mdpb=2bx4Nto-hFORk=qiOkoCg@mail.gmail.com/
total: 0 errors, 3 warnings, 0 checks, 15 lines checked
NOTE: For some of the reported defects, checkpatch may be able to
mechanically convert to the typical style using --fix or --fix-inplace.
/github/workspace/src/src/13229023.patch has style problems, please review.
NOTE: Ignored message types: UNKNOWN_COMMIT_ID
NOTE: If any of the errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.
[v3,3/6] Bluetooth: Fix UAF in hci_conn_hash_flush again
WARNING: Reported-by: should be immediately followed by Link: with a URL to the report
#93:
Reported-by: [email protected]
Closes: https://lore.kernel.org/linux-bluetooth/[email protected]/
WARNING: Possible unwrapped commit description (prefer a maximum 75 chars per line)
#94:
Closes: https://lore.kernel.org/linux-bluetooth/[email protected]/
WARNING: Unknown link reference 'Closes:', use 'Link:' instead
#94:
Closes: https://lore.kernel.org/linux-bluetooth/[email protected]/
total: 0 errors, 3 warnings, 0 checks, 58 lines checked
NOTE: For some of the reported defects, checkpatch may be able to
mechanically convert to the typical style using --fix or --fix-inplace.
/github/workspace/src/src/13229024.patch has style problems, please review.
NOTE: Ignored message types: UNKNOWN_COMMIT_ID
NOTE: If any of the errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.
##############################
Test: GitLint - FAIL
Desc: Run gitlint
Output:
[v3,1/6] Bluetooth: Fix potential double free caused by hci_conn_unlink
WARNING: I3 - ignore-body-lines: gitlint will be switching from using Python regex 'match' (match beginning) to 'search' (match anywhere) semantics. Please review your ignore-body-lines.regex option accordingly. To remove this warning, set general.regex-style-search=True. More details: https://jorisroovers.github.io/gitlint/configuration/#regex-style-search
13: B1 Line exceeds max length (88>80): "Closes: https://lore.kernel.org/linux-bluetooth/[email protected]/"
[v3,2/6] Bluetooth: Refcnt drop must be placed last in hci_conn_unlink
WARNING: I3 - ignore-body-lines: gitlint will be switching from using Python regex 'match' (match beginning) to 'search' (match anywhere) semantics. Please review your ignore-body-lines.regex option accordingly. To remove this warning, set general.regex-style-search=True. More details: https://jorisroovers.github.io/gitlint/configuration/#regex-style-search
13: B1 Line exceeds max length (115>80): "Closes: https://lore.kernel.org/linux-bluetooth/CABBYNZ+1kce8_RJrLNOXd_8=Mdpb=2bx4Nto-hFORk=qiOkoCg@mail.gmail.com/"
[v3,3/6] Bluetooth: Fix UAF in hci_conn_hash_flush again
WARNING: I3 - ignore-body-lines: gitlint will be switching from using Python regex 'match' (match beginning) to 'search' (match anywhere) semantics. Please review your ignore-body-lines.regex option accordingly. To remove this warning, set general.regex-style-search=True. More details: https://jorisroovers.github.io/gitlint/configuration/#regex-style-search
24: B1 Line exceeds max length (88>80): "Closes: https://lore.kernel.org/linux-bluetooth/[email protected]/"
[v3,4/6] Bluetooth: Perform hci_conn_drop in hci_conn_unlink
WARNING: I3 - ignore-body-lines: gitlint will be switching from using Python regex 'match' (match beginning) to 'search' (match anywhere) semantics. Please review your ignore-body-lines.regex option accordingly. To remove this warning, set general.regex-style-search=True. More details: https://jorisroovers.github.io/gitlint/configuration/#regex-style-search
13: B3 Line contains hard tab characters (\t): " hci_conn_unlink(conn) [conn->parent == NULL]"
14: B3 Line contains hard tab characters (\t): " -> hci_conn_unlink(child) [child->parent == conn]"
15: B3 Line contains hard tab characters (\t): " -> hci_conn_drop(child->parent)"
16: B3 Line contains hard tab characters (\t): " -> queue_delayed_work(&conn->disc_work)"
[v3,5/6] Bluetooth: Unlink CISes when LE disconnects in hci_conn_del
WARNING: I3 - ignore-body-lines: gitlint will be switching from using Python regex 'match' (match beginning) to 'search' (match anywhere) semantics. Please review your ignore-body-lines.regex option accordingly. To remove this warning, set general.regex-style-search=True. More details: https://jorisroovers.github.io/gitlint/configuration/#regex-style-search
13: B3 Line contains hard tab characters (\t): " All SCO, eSCO, and CIS connections on a physical link should be"
14: B3 Line contains hard tab characters (\t): " disconnected before the ACL connection on the same physical"
15: B3 Line contains hard tab characters (\t): " connection is disconnected. If it does not, they will be"
16: B3 Line contains hard tab characters (\t): " implicitly disconnected as part of the ACL disconnection."
17: B3 Line contains hard tab characters (\t): " ..."
18: B3 Line contains hard tab characters (\t): " Note: As specified in Section 7.7.5, on the Central, the handle"
19: B3 Line contains hard tab characters (\t): " for a CIS remains valid even after disconnection and, therefore,"
20: B3 Line contains hard tab characters (\t): " the Host can recreate a disconnected CIS at a later point in"
21: B3 Line contains hard tab characters (\t): " time using the same connection handle."
---
Regards,
Linux Bluetooth