| From e9bd28a7c35c0261b83f945f18c5a351c15837b1 Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Mon, 15 Apr 2024 12:51:55 +0530 |
| Subject: scsi: qedi: Fix crash while reading debugfs attribute |
| |
| From: Manish Rangankar <mrangankar@marvell.com> |
| |
| [ Upstream commit 28027ec8e32ecbadcd67623edb290dad61e735b5 ] |
| |
| The qedi_dbg_do_not_recover_cmd_read() function invokes sprintf() directly |
| on a __user pointer, which results into the crash. |
| |
| To fix this issue, use a small local stack buffer for sprintf() and then |
| call simple_read_from_buffer(), which in turns make the copy_to_user() |
| call. |
| |
| BUG: unable to handle page fault for address: 00007f4801111000 |
| PGD 8000000864df6067 P4D 8000000864df6067 PUD 864df7067 PMD 846028067 PTE 0 |
| Oops: 0002 [#1] PREEMPT SMP PTI |
| Hardware name: HPE ProLiant DL380 Gen10/ProLiant DL380 Gen10, BIOS U30 06/15/2023 |
| RIP: 0010:memcpy_orig+0xcd/0x130 |
| RSP: 0018:ffffb7a18c3ffc40 EFLAGS: 00010202 |
| RAX: 00007f4801111000 RBX: 00007f4801111000 RCX: 000000000000000f |
| RDX: 000000000000000f RSI: ffffffffc0bfd7a0 RDI: 00007f4801111000 |
| RBP: ffffffffc0bfd7a0 R08: 725f746f6e5f6f64 R09: 3d7265766f636572 |
| R10: ffffb7a18c3ffd08 R11: 0000000000000000 R12: 00007f4881110fff |
| R13: 000000007fffffff R14: ffffb7a18c3ffca0 R15: ffffffffc0bfd7af |
| FS: 00007f480118a740(0000) GS:ffff98e38af00000(0000) knlGS:0000000000000000 |
| CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 |
| CR2: 00007f4801111000 CR3: 0000000864b8e001 CR4: 00000000007706e0 |
| DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 |
| DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 |
| PKRU: 55555554 |
| Call Trace: |
| <TASK> |
| ? __die_body+0x1a/0x60 |
| ? page_fault_oops+0x183/0x510 |
| ? exc_page_fault+0x69/0x150 |
| ? asm_exc_page_fault+0x22/0x30 |
| ? memcpy_orig+0xcd/0x130 |
| vsnprintf+0x102/0x4c0 |
| sprintf+0x51/0x80 |
| qedi_dbg_do_not_recover_cmd_read+0x2f/0x50 [qedi 6bcfdeeecdea037da47069eca2ba717c84a77324] |
| full_proxy_read+0x50/0x80 |
| vfs_read+0xa5/0x2e0 |
| ? folio_add_new_anon_rmap+0x44/0xa0 |
| ? set_pte_at+0x15/0x30 |
| ? do_pte_missing+0x426/0x7f0 |
| ksys_read+0xa5/0xe0 |
| do_syscall_64+0x58/0x80 |
| ? __count_memcg_events+0x46/0x90 |
| ? count_memcg_event_mm+0x3d/0x60 |
| ? handle_mm_fault+0x196/0x2f0 |
| ? do_user_addr_fault+0x267/0x890 |
| ? exc_page_fault+0x69/0x150 |
| entry_SYSCALL_64_after_hwframe+0x72/0xdc |
| RIP: 0033:0x7f4800f20b4d |
| |
| Tested-by: Martin Hoyer <mhoyer@redhat.com> |
| Reviewed-by: John Meneghini <jmeneghi@redhat.com> |
| Signed-off-by: Manish Rangankar <mrangankar@marvell.com> |
| Link: https://lore.kernel.org/r/20240415072155.30840-1-mrangankar@marvell.com |
| Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| drivers/scsi/qedi/qedi_debugfs.c | 12 ++++-------- |
| 1 file changed, 4 insertions(+), 8 deletions(-) |
| |
| diff --git a/drivers/scsi/qedi/qedi_debugfs.c b/drivers/scsi/qedi/qedi_debugfs.c |
| index 42f5afb60055c..6e724f47ab9e8 100644 |
| --- a/drivers/scsi/qedi/qedi_debugfs.c |
| +++ b/drivers/scsi/qedi/qedi_debugfs.c |
| @@ -120,15 +120,11 @@ static ssize_t |
| qedi_dbg_do_not_recover_cmd_read(struct file *filp, char __user *buffer, |
| size_t count, loff_t *ppos) |
| { |
| - size_t cnt = 0; |
| - |
| - if (*ppos) |
| - return 0; |
| + char buf[64]; |
| + int len; |
| |
| - cnt = sprintf(buffer, "do_not_recover=%d\n", qedi_do_not_recover); |
| - cnt = min_t(int, count, cnt - *ppos); |
| - *ppos += cnt; |
| - return cnt; |
| + len = sprintf(buf, "do_not_recover=%d\n", qedi_do_not_recover); |
| + return simple_read_from_buffer(buffer, count, ppos, buf, len); |
| } |
| |
| static int |
| -- |
| 2.43.0 |
| |
