5.4-stable review patch. If anyone has any objections, please let me know.
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From: Bart Van Assche bvanassche@acm.org
commit 90449f2d1e1f020835cba5417234636937dd657e upstream.
sg_finish_rem_req() calls blk_rq_unmap_user(). The latter function may sleep. Hence, call sg_finish_rem_req() with interrupts enabled instead of disabled.
Reported-by: syzbot+c01f8e6e73f20459912e@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-scsi/691560c4.a70a0220.3124cb.001a.GAE@google.... Cc: Hannes Reinecke hare@suse.de Cc: stable@vger.kernel.org Fixes: 97d27b0dd015 ("scsi: sg: close race condition in sg_remove_sfp_usercontext()") Signed-off-by: Bart Van Assche bvanassche@acm.org Link: https://patch.msgid.link/20251113181643.1108973-1-bvanassche@acm.org Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/scsi/sg.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
--- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -2214,9 +2214,17 @@ sg_remove_sfp_usercontext(struct work_st write_lock_irqsave(&sfp->rq_list_lock, iflags); while (!list_empty(&sfp->rq_list)) { srp = list_first_entry(&sfp->rq_list, Sg_request, entry); - sg_finish_rem_req(srp); list_del(&srp->entry); + write_unlock_irqrestore(&sfp->rq_list_lock, iflags); + + sg_finish_rem_req(srp); + /* + * sg_rq_end_io() uses srp->parentfp. Hence, only clear + * srp->parentfp after blk_mq_free_request() has been called. + */ srp->parentfp = NULL; + + write_lock_irqsave(&sfp->rq_list_lock, iflags); } write_unlock_irqrestore(&sfp->rq_list_lock, iflags);