diff options
| author | Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> | 2025-11-05 11:25:46 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-12-03 12:45:20 +0100 |
| commit | 63f511d3855f7f4b35dd63dbc58fc3d935a81268 (patch) | |
| tree | 5069ee6a50196f6f4ffa7757d2ffffb708fadaf5 | |
| parent | 11eeee00c94d770d4e45364060b5f1526dfe567b (diff) | |
scsi: target: tcm_loop: Fix segfault in tcm_loop_tpg_address_show()
commit e6965188f84a7883e6a0d3448e86b0cf29b24dfc upstream.
If the allocation of tl_hba->sh fails in tcm_loop_driver_probe() and we
attempt to dereference it in tcm_loop_tpg_address_show() we will get a
segfault, see below for an example. So, check tl_hba->sh before
dereferencing it.
Unable to allocate struct scsi_host
BUG: kernel NULL pointer dereference, address: 0000000000000194
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 1 PID: 8356 Comm: tokio-runtime-w Not tainted 6.6.104.2-4.azl3 #1
Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 09/28/2024
RIP: 0010:tcm_loop_tpg_address_show+0x2e/0x50 [tcm_loop]
...
Call Trace:
<TASK>
configfs_read_iter+0x12d/0x1d0 [configfs]
vfs_read+0x1b5/0x300
ksys_read+0x6f/0xf0
...
Cc: stable@vger.kernel.org
Fixes: 2628b352c3d4 ("tcm_loop: Show address of tpg in configfs")
Signed-off-by: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Allen Pais <apais@linux.microsoft.com>
Link: https://patch.msgid.link/1762370746-6304-1-git-send-email-hamzamahfooz@linux.microsoft.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/target/loopback/tcm_loop.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/target/loopback/tcm_loop.c b/drivers/target/loopback/tcm_loop.c index 5ae5d94c5b93..9360148e1f4e 100644 --- a/drivers/target/loopback/tcm_loop.c +++ b/drivers/target/loopback/tcm_loop.c @@ -933,6 +933,9 @@ static ssize_t tcm_loop_tpg_address_show(struct config_item *item, struct tcm_loop_tpg, tl_se_tpg); struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba; + if (!tl_hba->sh) + return -ENODEV; + return snprintf(page, PAGE_SIZE, "%d:0:%d\n", tl_hba->sh->host_no, tl_tpg->tl_tpgt); } |