BUG: KASAN: slab-out-of-bounds in try_to_unmap_one+0x1c4/0x1af0
Compiling kernel on an aarch64 server with the latest mainline (rc2) triggered this, [ 1463.931841] BUG: KASAN: slab-out-of-bounds in try_to_unmap_one+0x1c4/0x1af0 [ 1463.938969] Write of size 32 at addr 80897ce87b58 by task kworker/u513:0/5209 [ 1463.946678] [ 1463.948656] CPU: 38 PID: 5209 Comm: kworker/u513:0 Kdump: loaded Tainted: G WL4.20.0-rc2+ #4 [ 1463.958485] Hardware name: HPE Apollo 70 /C01_APACHE_MB , BIOS L50_5.13_1.0.6 07/10/2018 [ 1463.968450] Workqueue: writeback wb_workfn (flush-253:0) [ 1463.973848] Call trace: [ 1463.976622] dump_backtrace+0x0/0x2c8 [ 1463.980642] [ 1463.982239] Allocated by task 2: [ 1463.985528] kasan_kmalloc.part.1+0x40/0x108 [ 1463.989842] kasan_kmalloc+0xb4/0xc8 [ 1463.993500] kasan_slab_alloc+0x14/0x20 [ 1463.997630] kmem_cache_alloc_node+0x140/0x430 [ 1464.002241] copy_process.isra.2+0x39c/0x2e20 [ 1464.007009] _do_fork+0x120/0xa28 [ 1464.010595] kernel_thread+0x48/0x58 [ 1464.014206] kthreadd+0x3dc/0x478 [ 1464.017698] ret_from_fork+0x10/0x1c [ 1464.021466] [ 1464.022981] Freed by task 1391: [ 1464.026214] __kasan_slab_free+0x114/0x228 [ 1464.030447] kasan_slab_free+0x10/0x18 [ 1464.034305] kmem_cache_free+0x9c/0x3a8 [ 1464.038284] put_task_stack+0x94/0x110 [ 1464.042169] finish_task_switch+0x3b0/0x488 [ 1464.046850] __schedule+0x5e4/0xda0 [ 1464.050665] schedule+0xdc/0x240 [ 1464.054012] worker_thread+0x278/0xa70 [ 1464.058021] kthread+0x1c4/0x1d0 [ 1464.061393] ret_from_fork+0x10/0x1c [ 1464.065051] [ 1464.067005] The buggy address belongs to the object at 80897ce88000 [ 1464.067005] which belongs to the cache thread_stack of size 32768 [ 1464.080107] The buggy address is located 1192 bytes to the left of [ 1464.080107] 32768-byte region [80897ce88000, 80897ce9) [ 1464.092578] The buggy address belongs to the page: [ 1464.097529] page:7fe0225f3a00 count:1 mapcount:0 mapping:8089c0014d80 index:0x0 compound_mapcount: 0 [ 1464.107724] flags: 0x1f010200(slab|head) [ 1464.112648] raw: 1f010200 7fe02266a408 7fe022459408 8089c0014d80 [ 1464.120496] raw: 00050005 0001 [ 1464.128284] page dumped because: kasan: bad access detected [ 1464.134011] [ 1464.135619] Memory state around the buggy address: [ 1464.140576] 80897ce87a00: fc fc fc fc fc fc fc fc fc fc fc fc f1 f1 f1 f1 [ 1464.148063] 00 f2 f2 f2 f2 f2^ [ 1464.168846]7c00: f2 f2 f2 f2
BUG: KASAN: slab-out-of-bounds in try_to_unmap_one+0x1c4/0x1af0
Compiling kernel on an aarch64 server with the latest mainline (rc2) triggered this, [ 1463.931841] BUG: KASAN: slab-out-of-bounds in try_to_unmap_one+0x1c4/0x1af0 [ 1463.938969] Write of size 32 at addr 80897ce87b58 by task kworker/u513:0/5209 [ 1463.946678] [ 1463.948656] CPU: 38 PID: 5209 Comm: kworker/u513:0 Kdump: loaded Tainted: G WL4.20.0-rc2+ #4 [ 1463.958485] Hardware name: HPE Apollo 70 /C01_APACHE_MB , BIOS L50_5.13_1.0.6 07/10/2018 [ 1463.968450] Workqueue: writeback wb_workfn (flush-253:0) [ 1463.973848] Call trace: [ 1463.976622] dump_backtrace+0x0/0x2c8 [ 1463.980642] [ 1463.982239] Allocated by task 2: [ 1463.985528] kasan_kmalloc.part.1+0x40/0x108 [ 1463.989842] kasan_kmalloc+0xb4/0xc8 [ 1463.993500] kasan_slab_alloc+0x14/0x20 [ 1463.997630] kmem_cache_alloc_node+0x140/0x430 [ 1464.002241] copy_process.isra.2+0x39c/0x2e20 [ 1464.007009] _do_fork+0x120/0xa28 [ 1464.010595] kernel_thread+0x48/0x58 [ 1464.014206] kthreadd+0x3dc/0x478 [ 1464.017698] ret_from_fork+0x10/0x1c [ 1464.021466] [ 1464.022981] Freed by task 1391: [ 1464.026214] __kasan_slab_free+0x114/0x228 [ 1464.030447] kasan_slab_free+0x10/0x18 [ 1464.034305] kmem_cache_free+0x9c/0x3a8 [ 1464.038284] put_task_stack+0x94/0x110 [ 1464.042169] finish_task_switch+0x3b0/0x488 [ 1464.046850] __schedule+0x5e4/0xda0 [ 1464.050665] schedule+0xdc/0x240 [ 1464.054012] worker_thread+0x278/0xa70 [ 1464.058021] kthread+0x1c4/0x1d0 [ 1464.061393] ret_from_fork+0x10/0x1c [ 1464.065051] [ 1464.067005] The buggy address belongs to the object at 80897ce88000 [ 1464.067005] which belongs to the cache thread_stack of size 32768 [ 1464.080107] The buggy address is located 1192 bytes to the left of [ 1464.080107] 32768-byte region [80897ce88000, 80897ce9) [ 1464.092578] The buggy address belongs to the page: [ 1464.097529] page:7fe0225f3a00 count:1 mapcount:0 mapping:8089c0014d80 index:0x0 compound_mapcount: 0 [ 1464.107724] flags: 0x1f010200(slab|head) [ 1464.112648] raw: 1f010200 7fe02266a408 7fe022459408 8089c0014d80 [ 1464.120496] raw: 00050005 0001 [ 1464.128284] page dumped because: kasan: bad access detected [ 1464.134011] [ 1464.135619] Memory state around the buggy address: [ 1464.140576] 80897ce87a00: fc fc fc fc fc fc fc fc fc fc fc fc f1 f1 f1 f1 [ 1464.148063] 00 f2 f2 f2 f2 f2^ [ 1464.168846]7c00: f2 f2 f2 f2
