mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-04-29 11:44:39 -04:00
0355d6c1d5
After commita2c11b0341("kcm: use BPF_PROG_RUN") syzbot easily triggers the warning in cant_sleep(). As explained in commit6cab5e90ab("bpf: run bpf programs with preemption disabled") we need to disable preemption before running bpf programs. BUG: assuming atomic context at net/kcm/kcmsock.c:382 in_atomic(): 0, irqs_disabled(): 0, pid: 7, name: kworker/u4:0 3 locks held by kworker/u4:0/7: #0: ffff888216726128 ((wq_completion)kstrp){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff888216726128 ((wq_completion)kstrp){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888216726128 ((wq_completion)kstrp){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff888216726128 ((wq_completion)kstrp){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff888216726128 ((wq_completion)kstrp){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff888216726128 ((wq_completion)kstrp){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff888216726128 ((wq_completion)kstrp){+.+.}, at: process_one_work+0x88b/0x1740 kernel/workqueue.c:2240 #1: ffff8880a989fdc0 ((work_completion)(&strp->work)){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2244 #2: ffff888098998d10 (sk_lock-AF_INET){+.+.}, at: lock_sock include/net/sock.h:1522 [inline] #2: ffff888098998d10 (sk_lock-AF_INET){+.+.}, at: strp_sock_lock+0x2e/0x40 net/strparser/strparser.c:440 CPU: 0 PID: 7 Comm: kworker/u4:0 Not tainted 5.3.0+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: kstrp strp_work Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 __cant_sleep kernel/sched/core.c:6826 [inline] __cant_sleep.cold+0xa4/0xbc kernel/sched/core.c:6803 kcm_parse_func_strparser+0x54/0x200 net/kcm/kcmsock.c:382 __strp_recv+0x5dc/0x1b20 net/strparser/strparser.c:221 strp_recv+0xcf/0x10b net/strparser/strparser.c:343 tcp_read_sock+0x285/0xa00 net/ipv4/tcp.c:1639 strp_read_sock+0x14d/0x200 net/strparser/strparser.c:366 do_strp_work net/strparser/strparser.c:414 [inline] strp_work+0xe3/0x130 net/strparser/strparser.c:423 process_one_work+0x9af/0x1740 kernel/workqueue.c:2269 Fixes:a2c11b0341("kcm: use BPF_PROG_RUN") Fixes:6cab5e90ab("bpf: run bpf programs with preemption disabled") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.