From: Manish Rangankar <mrangankar@xxxxxxxxxxx> [ 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@xxxxxxxxxx> Reviewed-by: John Meneghini <jmeneghi@xxxxxxxxxx> Signed-off-by: Manish Rangankar <mrangankar@xxxxxxxxxxx> Link: https://lore.kernel.org/r/20240415072155.30840-1-mrangankar@xxxxxxxxxxx Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- 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
