From 8d59fba49362c65332395789fd82771f1028d87e Mon Sep 17 00:00:00 2001 From: Ilia Gavrilov Date: Mon, 20 Oct 2025 15:12:55 +0000 Subject: [PATCH] Bluetooth: MGMT: Fix OOB access in parse_adv_monitor_pattern() In the parse_adv_monitor_pattern() function, the value of the 'length' variable is currently limited to HCI_MAX_EXT_AD_LENGTH(251). The size of the 'value' array in the mgmt_adv_pattern structure is 31. If the value of 'pattern[i].length' is set in the user space and exceeds 31, the 'patterns[i].value' array can be accessed out of bound when copied. Increasing the size of the 'value' array in the 'mgmt_adv_pattern' structure will break the userspace. Considering this, and to avoid OOB access revert the limits for 'offset' and 'length' back to the value of HCI_MAX_AD_LENGTH. Found by InfoTeCS on behalf of Linux Verification Center (linuxtesting.org) with SVACE. Fixes: db08722fc7d4 ("Bluetooth: hci_core: Fix missing instances using HCI_MAX_AD_LENGTH") Cc: stable@vger.kernel.org Signed-off-by: Ilia Gavrilov Signed-off-by: Luiz Augusto von Dentz --- include/net/bluetooth/mgmt.h | 2 +- net/bluetooth/mgmt.c | 6 +++--- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/include/net/bluetooth/mgmt.h b/include/net/bluetooth/mgmt.h index bca0333f1e99..f5be96f08b9d 100644 --- a/include/net/bluetooth/mgmt.h +++ b/include/net/bluetooth/mgmt.h @@ -780,7 +780,7 @@ struct mgmt_adv_pattern { __u8 ad_type; __u8 offset; __u8 length; - __u8 value[31]; + __u8 value[HCI_MAX_AD_LENGTH]; } __packed; #define MGMT_OP_ADD_ADV_PATTERNS_MONITOR 0x0052 diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c index 24e335e3a727..79762bfaea5f 100644 --- a/net/bluetooth/mgmt.c +++ b/net/bluetooth/mgmt.c @@ -5395,9 +5395,9 @@ static u8 parse_adv_monitor_pattern(struct adv_monitor *m, u8 pattern_count, for (i = 0; i < pattern_count; i++) { offset = patterns[i].offset; length = patterns[i].length; - if (offset >= HCI_MAX_EXT_AD_LENGTH || - length > HCI_MAX_EXT_AD_LENGTH || - (offset + length) > HCI_MAX_EXT_AD_LENGTH) + if (offset >= HCI_MAX_AD_LENGTH || + length > HCI_MAX_AD_LENGTH || + (offset + length) > HCI_MAX_AD_LENGTH) return MGMT_STATUS_INVALID_PARAMS; p = kmalloc(sizeof(*p), GFP_KERNEL); -- 2.47.3