| Message ID | 20211013033913.2551004-2-yebin10@huawei.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | Fix out-of-bound read in resp_readcap16 and resp_report_tgtpgs | expand |
On 2021-10-12 11:39 p.m., Ye Bin wrote: > We got following warning when runing syzkaller: > [ 3813.830724] sg_write: data in/out 65466/242 bytes for SCSI command 0x9e-- guessing data in; > [ 3813.830724] program syz-executor not setting count and/or reply_len properly > [ 3813.836956] ================================================================== > [ 3813.839465] BUG: KASAN: stack-out-of-bounds in sg_copy_buffer+0x157/0x1e0 > [ 3813.841773] Read of size 4096 at addr ffff8883cf80f540 by task syz-executor/1549 > [ 3813.846612] Call Trace: > [ 3813.846995] dump_stack+0x108/0x15f > [ 3813.847524] print_address_description+0xa5/0x372 > [ 3813.848243] kasan_report.cold+0x236/0x2a8 > [ 3813.849439] check_memory_region+0x240/0x270 > [ 3813.850094] memcpy+0x30/0x80 > [ 3813.850553] sg_copy_buffer+0x157/0x1e0 > [ 3813.853032] sg_copy_from_buffer+0x13/0x20 > [ 3813.853660] fill_from_dev_buffer+0x135/0x370 > [ 3813.854329] resp_readcap16+0x1ac/0x280 > [ 3813.856917] schedule_resp+0x41f/0x1630 > [ 3813.858203] scsi_debug_queuecommand+0xb32/0x17e0 > [ 3813.862699] scsi_dispatch_cmd+0x330/0x950 > [ 3813.863329] scsi_request_fn+0xd8e/0x1710 > [ 3813.863946] __blk_run_queue+0x10b/0x230 > [ 3813.864544] blk_execute_rq_nowait+0x1d8/0x400 > [ 3813.865220] sg_common_write.isra.0+0xe61/0x2420 > [ 3813.871637] sg_write+0x6c8/0xef0 > [ 3813.878853] __vfs_write+0xe4/0x800 > [ 3813.883487] vfs_write+0x17b/0x530 > [ 3813.884008] ksys_write+0x103/0x270 > [ 3813.886268] __x64_sys_write+0x77/0xc0 > [ 3813.886841] do_syscall_64+0x106/0x360 > [ 3813.887415] entry_SYSCALL_64_after_hwframe+0x44/0xa9 > > We can reproduce this issue with following syzkaller log: > r0 = openat(0xffffffffffffff9c, &(0x7f0000000040)='./file0\x00', 0x26e1, 0x0) > r1 = syz_open_procfs(0xffffffffffffffff, &(0x7f0000000000)='fd/3\x00') > open_by_handle_at(r1, &(0x7f00000003c0)=ANY=[@ANYRESHEX], 0x602000) > r2 = syz_open_dev$sg(&(0x7f0000000000), 0x0, 0x40782) > write$binfmt_aout(r2, &(0x7f0000000340)=ANY=[@ANYBLOB="00000000deff000000000000000000000000000000000000000000000000000047f007af9e107a41ec395f1bded7be24277a1501ff6196a83366f4e6362bc0ff2b247f68a972989b094b2da4fb3607fcf611a22dd04310d28c75039d"], 0x126) > > As in resp_readcap16 we get "int alloc_len" value -1104926854, and then pass > huge arr_len to fill_from_dev_buffer, but arr is only has 32 bytes space. So > lead to OOB in sg_copy_buffer. > To solve this issue just define alloc_len with U32 type. > > Signed-off-by: Ye Bin <yebin10@huawei.com> Acked-by: Douglas Gilbert <dgilbert@interlog.com> Thanks. > --- > drivers/scsi/scsi_debug.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c > index 66f507469a31..be0440545744 100644 > --- a/drivers/scsi/scsi_debug.c > +++ b/drivers/scsi/scsi_debug.c > @@ -1856,7 +1856,7 @@ static int resp_readcap16(struct scsi_cmnd *scp, > { > unsigned char *cmd = scp->cmnd; > unsigned char arr[SDEBUG_READCAP16_ARR_SZ]; > - int alloc_len; > + u32 alloc_len; > > alloc_len = get_unaligned_be32(cmd + 10); > /* following just in case virtual_gb changed */ > @@ -1885,7 +1885,7 @@ static int resp_readcap16(struct scsi_cmnd *scp, > } > > return fill_from_dev_buffer(scp, arr, > - min_t(int, alloc_len, SDEBUG_READCAP16_ARR_SZ)); > + min_t(u32, alloc_len, SDEBUG_READCAP16_ARR_SZ)); > } > > #define SDEBUG_MAX_TGTPGS_ARR_SZ 1412 >
diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c index 66f507469a31..be0440545744 100644 --- a/drivers/scsi/scsi_debug.c +++ b/drivers/scsi/scsi_debug.c @@ -1856,7 +1856,7 @@ static int resp_readcap16(struct scsi_cmnd *scp, { unsigned char *cmd = scp->cmnd; unsigned char arr[SDEBUG_READCAP16_ARR_SZ]; - int alloc_len; + u32 alloc_len; alloc_len = get_unaligned_be32(cmd + 10); /* following just in case virtual_gb changed */ @@ -1885,7 +1885,7 @@ static int resp_readcap16(struct scsi_cmnd *scp, } return fill_from_dev_buffer(scp, arr, - min_t(int, alloc_len, SDEBUG_READCAP16_ARR_SZ)); + min_t(u32, alloc_len, SDEBUG_READCAP16_ARR_SZ)); } #define SDEBUG_MAX_TGTPGS_ARR_SZ 1412
We got following warning when runing syzkaller: [ 3813.830724] sg_write: data in/out 65466/242 bytes for SCSI command 0x9e-- guessing data in; [ 3813.830724] program syz-executor not setting count and/or reply_len properly [ 3813.836956] ================================================================== [ 3813.839465] BUG: KASAN: stack-out-of-bounds in sg_copy_buffer+0x157/0x1e0 [ 3813.841773] Read of size 4096 at addr ffff8883cf80f540 by task syz-executor/1549 [ 3813.846612] Call Trace: [ 3813.846995] dump_stack+0x108/0x15f [ 3813.847524] print_address_description+0xa5/0x372 [ 3813.848243] kasan_report.cold+0x236/0x2a8 [ 3813.849439] check_memory_region+0x240/0x270 [ 3813.850094] memcpy+0x30/0x80 [ 3813.850553] sg_copy_buffer+0x157/0x1e0 [ 3813.853032] sg_copy_from_buffer+0x13/0x20 [ 3813.853660] fill_from_dev_buffer+0x135/0x370 [ 3813.854329] resp_readcap16+0x1ac/0x280 [ 3813.856917] schedule_resp+0x41f/0x1630 [ 3813.858203] scsi_debug_queuecommand+0xb32/0x17e0 [ 3813.862699] scsi_dispatch_cmd+0x330/0x950 [ 3813.863329] scsi_request_fn+0xd8e/0x1710 [ 3813.863946] __blk_run_queue+0x10b/0x230 [ 3813.864544] blk_execute_rq_nowait+0x1d8/0x400 [ 3813.865220] sg_common_write.isra.0+0xe61/0x2420 [ 3813.871637] sg_write+0x6c8/0xef0 [ 3813.878853] __vfs_write+0xe4/0x800 [ 3813.883487] vfs_write+0x17b/0x530 [ 3813.884008] ksys_write+0x103/0x270 [ 3813.886268] __x64_sys_write+0x77/0xc0 [ 3813.886841] do_syscall_64+0x106/0x360 [ 3813.887415] entry_SYSCALL_64_after_hwframe+0x44/0xa9 We can reproduce this issue with following syzkaller log: r0 = openat(0xffffffffffffff9c, &(0x7f0000000040)='./file0\x00', 0x26e1, 0x0) r1 = syz_open_procfs(0xffffffffffffffff, &(0x7f0000000000)='fd/3\x00') open_by_handle_at(r1, &(0x7f00000003c0)=ANY=[@ANYRESHEX], 0x602000) r2 = syz_open_dev$sg(&(0x7f0000000000), 0x0, 0x40782) write$binfmt_aout(r2, &(0x7f0000000340)=ANY=[@ANYBLOB="00000000deff000000000000000000000000000000000000000000000000000047f007af9e107a41ec395f1bded7be24277a1501ff6196a83366f4e6362bc0ff2b247f68a972989b094b2da4fb3607fcf611a22dd04310d28c75039d"], 0x126) As in resp_readcap16 we get "int alloc_len" value -1104926854, and then pass huge arr_len to fill_from_dev_buffer, but arr is only has 32 bytes space. So lead to OOB in sg_copy_buffer. To solve this issue just define alloc_len with U32 type. Signed-off-by: Ye Bin <yebin10@huawei.com> --- drivers/scsi/scsi_debug.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)