From: Herbert Xu herbert@gondor.apana.org.au
[ Upstream commit 58329c4312031603bb1786b44265c26d5065fe72 ]
As the old padata code can execute in softirq context, disable softirqs for the new padata_do_mutithreaded code too as otherwise lockdep will get antsy.
Reported-by: syzbot+0cb5bb0f4bf9e79db3b3@syzkaller.appspotmail.com Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Acked-by: Daniel Jordan daniel.m.jordan@oracle.com Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/padata.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/kernel/padata.c b/kernel/padata.c index fdcd78302cd72..471ccbc44541d 100644 --- a/kernel/padata.c +++ b/kernel/padata.c @@ -111,7 +111,7 @@ static int __init padata_work_alloc_mt(int nworks, void *data, { int i;
- spin_lock(&padata_works_lock); + spin_lock_bh(&padata_works_lock); /* Start at 1 because the current task participates in the job. */ for (i = 1; i < nworks; ++i) { struct padata_work *pw = padata_work_alloc(); @@ -121,7 +121,7 @@ static int __init padata_work_alloc_mt(int nworks, void *data, padata_work_init(pw, padata_mt_helper, data, 0); list_add(&pw->pw_list, head); } - spin_unlock(&padata_works_lock); + spin_unlock_bh(&padata_works_lock);
return i; } @@ -139,12 +139,12 @@ static void __init padata_works_free(struct list_head *works) if (list_empty(works)) return;
- spin_lock(&padata_works_lock); + spin_lock_bh(&padata_works_lock); list_for_each_entry_safe(cur, next, works, pw_list) { list_del(&cur->pw_list); padata_work_free(cur); } - spin_unlock(&padata_works_lock); + spin_unlock_bh(&padata_works_lock); }
static void padata_parallel_worker(struct work_struct *parallel_work)
From: "Paul E. McKenney" paulmck@kernel.org
[ Upstream commit 8b9b443fa860276822b25057cb3ff3b28734dec0 ]
The "pipe_count > RCU_TORTURE_PIPE_LEN" check has a comment saying "Should not happen, but...". This is only true when testing an RCU whose grace periods are always long enough. This commit therefore fixes this comment.
Reported-by: Linus Torvalds torvalds@linux-foundation.org Closes: https://lore.kernel.org/lkml/CAHk-=wi7rJ-eGq+xaxVfzFEgbL9tdf6Kc8Z89rCpfcQOKm... Signed-off-by: Paul E. McKenney paulmck@kernel.org Signed-off-by: Uladzislau Rezki (Sony) urezki@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/rcu/rcutorture.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index 6c1aea48a79a1..c413eb4a95667 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -1407,7 +1407,8 @@ static bool rcu_torture_one_read(struct torture_random_state *trsp) preempt_disable(); pipe_count = READ_ONCE(p->rtort_pipe_count); if (pipe_count > RCU_TORTURE_PIPE_LEN) { - /* Should not happen, but... */ + // Should not happen in a correct RCU implementation, + // happens quite often for torture_type=busted. pipe_count = RCU_TORTURE_PIPE_LEN; } completed = cur_ops->get_gp_seq();
From: Zqiang qiang.zhang1211@gmail.com
[ Upstream commit 668c0406d887467d53f8fe79261dda1d22d5b671 ]
When the torture_type is set srcu or srcud and cb_barrier is non-zero, running the rcutorture test will trigger the following warning:
[ 163.910989][ C1] BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48 [ 163.910994][ C1] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 0, name: swapper/1 [ 163.910999][ C1] preempt_count: 10001, expected: 0 [ 163.911002][ C1] RCU nest depth: 0, expected: 0 [ 163.911005][ C1] INFO: lockdep is turned off. [ 163.911007][ C1] irq event stamp: 30964 [ 163.911010][ C1] hardirqs last enabled at (30963): [<ffffffffabc7df52>] do_idle+0x362/0x500 [ 163.911018][ C1] hardirqs last disabled at (30964): [<ffffffffae616eff>] sysvec_call_function_single+0xf/0xd0 [ 163.911025][ C1] softirqs last enabled at (0): [<ffffffffabb6475f>] copy_process+0x16ff/0x6580 [ 163.911033][ C1] softirqs last disabled at (0): [<0000000000000000>] 0x0 [ 163.911038][ C1] Preemption disabled at: [ 163.911039][ C1] [<ffffffffacf1964b>] stack_depot_save_flags+0x24b/0x6c0 [ 163.911063][ C1] CPU: 1 PID: 0 Comm: swapper/1 Tainted: G W 6.8.0-rc4-rt4-yocto-preempt-rt+ #3 1e39aa9a737dd024a3275c4f835a872f673a7d3a [ 163.911071][ C1] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014 [ 163.911075][ C1] Call Trace: [ 163.911078][ C1] <IRQ> [ 163.911080][ C1] dump_stack_lvl+0x88/0xd0 [ 163.911089][ C1] dump_stack+0x10/0x20 [ 163.911095][ C1] __might_resched+0x36f/0x530 [ 163.911105][ C1] rt_spin_lock+0x82/0x1c0 [ 163.911112][ C1] spin_lock_irqsave_ssp_contention+0xb8/0x100 [ 163.911121][ C1] srcu_gp_start_if_needed+0x782/0xf00 [ 163.911128][ C1] ? _raw_spin_unlock_irqrestore+0x46/0x70 [ 163.911136][ C1] ? debug_object_active_state+0x336/0x470 [ 163.911148][ C1] ? __pfx_srcu_gp_start_if_needed+0x10/0x10 [ 163.911156][ C1] ? __pfx_lock_release+0x10/0x10 [ 163.911165][ C1] ? __pfx_rcu_torture_barrier_cbf+0x10/0x10 [ 163.911188][ C1] __call_srcu+0x9f/0xe0 [ 163.911196][ C1] call_srcu+0x13/0x20 [ 163.911201][ C1] srcu_torture_call+0x1b/0x30 [ 163.911224][ C1] rcu_torture_barrier1cb+0x4a/0x60 [ 163.911247][ C1] __flush_smp_call_function_queue+0x267/0xca0 [ 163.911256][ C1] ? __pfx_rcu_torture_barrier1cb+0x10/0x10 [ 163.911281][ C1] generic_smp_call_function_single_interrupt+0x13/0x20 [ 163.911288][ C1] __sysvec_call_function_single+0x7d/0x280 [ 163.911295][ C1] sysvec_call_function_single+0x93/0xd0 [ 163.911302][ C1] </IRQ> [ 163.911304][ C1] <TASK> [ 163.911308][ C1] asm_sysvec_call_function_single+0x1b/0x20 [ 163.911313][ C1] RIP: 0010:default_idle+0x17/0x20 [ 163.911326][ C1] RSP: 0018:ffff888001997dc8 EFLAGS: 00000246 [ 163.911333][ C1] RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffffffffae618b51 [ 163.911337][ C1] RDX: 0000000000000000 RSI: ffffffffaea80920 RDI: ffffffffaec2de80 [ 163.911342][ C1] RBP: ffff888001997dc8 R08: 0000000000000001 R09: ffffed100d740cad [ 163.911346][ C1] R10: ffffed100d740cac R11: ffff88806ba06563 R12: 0000000000000001 [ 163.911350][ C1] R13: ffffffffafe460c0 R14: ffffffffafe460c0 R15: 0000000000000000 [ 163.911358][ C1] ? ct_kernel_exit.constprop.3+0x121/0x160 [ 163.911369][ C1] ? lockdep_hardirqs_on+0xc4/0x150 [ 163.911376][ C1] arch_cpu_idle+0x9/0x10 [ 163.911383][ C1] default_idle_call+0x7a/0xb0 [ 163.911390][ C1] do_idle+0x362/0x500 [ 163.911398][ C1] ? __pfx_do_idle+0x10/0x10 [ 163.911404][ C1] ? complete_with_flags+0x8b/0xb0 [ 163.911416][ C1] cpu_startup_entry+0x58/0x70 [ 163.911423][ C1] start_secondary+0x221/0x280 [ 163.911430][ C1] ? __pfx_start_secondary+0x10/0x10 [ 163.911440][ C1] secondary_startup_64_no_verify+0x17f/0x18b [ 163.911455][ C1] </TASK>
This commit therefore use smp_call_on_cpu() instead of smp_call_function_single(), make rcu_torture_barrier1cb() invoked happens on task-context.
Signed-off-by: Zqiang qiang.zhang1211@gmail.com Signed-off-by: Paul E. McKenney paulmck@kernel.org Signed-off-by: Uladzislau Rezki (Sony) urezki@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/rcu/rcutorture.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index c413eb4a95667..9f505688291e5 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -2210,11 +2210,12 @@ static void rcu_torture_barrier_cbf(struct rcu_head *rcu) }
/* IPI handler to get callback posted on desired CPU, if online. */ -static void rcu_torture_barrier1cb(void *rcu_void) +static int rcu_torture_barrier1cb(void *rcu_void) { struct rcu_head *rhp = rcu_void;
cur_ops->call(rhp, rcu_torture_barrier_cbf); + return 0; }
/* kthread function to register callbacks used to test RCU barriers. */ @@ -2240,11 +2241,9 @@ static int rcu_torture_barrier_cbs(void *arg) * The above smp_load_acquire() ensures barrier_phase load * is ordered before the following ->call(). */ - if (smp_call_function_single(myid, rcu_torture_barrier1cb, - &rcu, 1)) { - // IPI failed, so use direct call from current CPU. + if (smp_call_on_cpu(myid, rcu_torture_barrier1cb, &rcu, 1)) cur_ops->call(&rcu, rcu_torture_barrier_cbf); - } + if (atomic_dec_and_test(&barrier_cbs_count)) wake_up(&barrier_wq); } while (!torture_must_stop());
From: Kees Cook keescook@chromium.org
[ Upstream commit 2a5eb9995528441447d33838727f6ec1caf08139 ]
Currently the brk starts its randomization immediately after .bss, which means there is a chance that when the random offset is 0, linear overflows from .bss can reach into the brk area. Leave at least a single page gap between .bss and brk (when it has not already been explicitly relocated into the mmap range).
Reported-by: y0un9n132@gmail.com Closes: https://lore.kernel.org/linux-hardening/CA+2EKTVLvc8hDZc+2Yhwmus=dzOUG5E4gV7... Link: https://lore.kernel.org/r/20240217062545.1631668-2-keescook@chromium.org Signed-off-by: Kees Cook keescook@chromium.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/binfmt_elf.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c index ccc4c6d8a578f..d5f9ad0651ea5 100644 --- a/fs/binfmt_elf.c +++ b/fs/binfmt_elf.c @@ -1286,6 +1286,9 @@ static int load_elf_binary(struct linux_binprm *bprm) if (IS_ENABLED(CONFIG_ARCH_HAS_ELF_RANDOMIZE) && elf_ex->e_type == ET_DYN && !interpreter) { mm->brk = mm->start_brk = ELF_ET_DYN_BASE; + } else { + /* Otherwise leave a gap between .bss and brk. */ + mm->brk = mm->start_brk = mm->brk + PAGE_SIZE; }
mm->brk = mm->start_brk = arch_randomize_brk(mm);
From: Justin Stitt justinstitt@google.com
[ Upstream commit ccb326b5f9e623eb7f130fbbf2505ec0e2dcaff9 ]
Running syzkaller with the newly reintroduced signed integer overflow sanitizer shows this report:
[ 62.982337] ------------[ cut here ]------------ [ 62.985692] cgroup: Invalid name [ 62.986211] UBSAN: signed-integer-overflow in ../block/ioctl.c:36:46 [ 62.989370] 9pnet_fd: p9_fd_create_tcp (7343): problem connecting socket to 127.0.0.1 [ 62.992992] 9223372036854775807 + 4095 cannot be represented in type 'long long' [ 62.997827] 9pnet_fd: p9_fd_create_tcp (7345): problem connecting socket to 127.0.0.1 [ 62.999369] random: crng reseeded on system resumption [ 63.000634] GUP no longer grows the stack in syz-executor.2 (7353): 20002000-20003000 (20001000) [ 63.000668] CPU: 0 PID: 7353 Comm: syz-executor.2 Not tainted 6.8.0-rc2-00035-gb3ef86b5a957 #1 [ 63.000677] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 63.000682] Call Trace: [ 63.000686] <TASK> [ 63.000731] dump_stack_lvl+0x93/0xd0 [ 63.000919] __get_user_pages+0x903/0xd30 [ 63.001030] __gup_longterm_locked+0x153e/0x1ba0 [ 63.001041] ? _raw_read_unlock_irqrestore+0x17/0x50 [ 63.001072] ? try_get_folio+0x29c/0x2d0 [ 63.001083] internal_get_user_pages_fast+0x1119/0x1530 [ 63.001109] iov_iter_extract_pages+0x23b/0x580 [ 63.001206] bio_iov_iter_get_pages+0x4de/0x1220 [ 63.001235] iomap_dio_bio_iter+0x9b6/0x1410 [ 63.001297] __iomap_dio_rw+0xab4/0x1810 [ 63.001316] iomap_dio_rw+0x45/0xa0 [ 63.001328] ext4_file_write_iter+0xdde/0x1390 [ 63.001372] vfs_write+0x599/0xbd0 [ 63.001394] ksys_write+0xc8/0x190 [ 63.001403] do_syscall_64+0xd4/0x1b0 [ 63.001421] ? arch_exit_to_user_mode_prepare+0x3a/0x60 [ 63.001479] entry_SYSCALL_64_after_hwframe+0x6f/0x77 [ 63.001535] RIP: 0033:0x7f7fd3ebf539 [ 63.001551] Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 [ 63.001562] RSP: 002b:00007f7fd32570c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 63.001584] RAX: ffffffffffffffda RBX: 00007f7fd3ff3f80 RCX: 00007f7fd3ebf539 [ 63.001590] RDX: 4db6d1e4f7e43360 RSI: 0000000020000000 RDI: 0000000000000004 [ 63.001595] RBP: 00007f7fd3f1e496 R08: 0000000000000000 R09: 0000000000000000 [ 63.001599] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 63.001604] R13: 0000000000000006 R14: 00007f7fd3ff3f80 R15: 00007ffd415ad2b8 ... [ 63.018142] ---[ end trace ]---
Historically, the signed integer overflow sanitizer did not work in the kernel due to its interaction with `-fwrapv` but this has since been changed [1] in the newest version of Clang; It was re-enabled in the kernel with Commit 557f8c582a9ba8ab ("ubsan: Reintroduce signed overflow sanitizer").
Let's rework this overflow checking logic to not actually perform an overflow during the check itself, thus avoiding the UBSAN splat.
[1]: https://github.com/llvm/llvm-project/pull/82432
Signed-off-by: Justin Stitt justinstitt@google.com Reviewed-by: Christoph Hellwig hch@lst.de Link: https://lore.kernel.org/r/20240507-b4-sio-block-ioctl-v3-1-ba0c2b32275e@goog... Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- block/ioctl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/block/ioctl.c b/block/ioctl.c index bc97698e0e8a3..11e692741f17c 100644 --- a/block/ioctl.c +++ b/block/ioctl.c @@ -32,7 +32,7 @@ static int blkpg_do_ioctl(struct block_device *bdev, if (op == BLKPG_DEL_PARTITION) return bdev_del_partition(bdev, p.pno);
- if (p.start < 0 || p.length <= 0 || p.start + p.length < 0) + if (p.start < 0 || p.length <= 0 || LLONG_MAX - p.length < p.start) return -EINVAL; /* Check that the partition is aligned to the block size */ if (!IS_ALIGNED(p.start | p.length, bdev_logical_block_size(bdev)))
linux-stable-mirror@lists.linaro.org