On Mon, Sep 13, 2021 at 09:52:33PM +0530, Naresh Kamboju wrote:
On Mon, 13 Sept 2021 at 19:51, Greg Kroah-Hartman gregkh@linuxfoundation.org wrote:
From: Baokun Li libaokun1@huawei.com
[ Upstream commit fad7cd3310db3099f95dd34312c77740fbc455e5 ]
If user specify a large enough value of NBD blocks option, it may trigger signed integer overflow which may lead to nbd->config->bytesize becomes a large or small value, zero in particular.
UBSAN: Undefined behaviour in drivers/block/nbd.c:325:31 signed integer overflow: 1024 * 4611686155866341414 cannot be represented in type 'long long int' [...] Call trace: [...] handle_overflow+0x188/0x1dc lib/ubsan.c:192 __ubsan_handle_mul_overflow+0x34/0x44 lib/ubsan.c:213 nbd_size_set drivers/block/nbd.c:325 [inline] __nbd_ioctl drivers/block/nbd.c:1342 [inline] nbd_ioctl+0x998/0xa10 drivers/block/nbd.c:1395 __blkdev_driver_ioctl block/ioctl.c:311 [inline] [...]
Although it is not a big deal, still silence the UBSAN by limit the input value.
Reported-by: Hulk Robot hulkci@huawei.com Signed-off-by: Baokun Li libaokun1@huawei.com Reviewed-by: Josef Bacik josef@toxicpanda.com Link: https://lore.kernel.org/r/20210804021212.990223-1-libaokun1@huawei.com [axboe: dropped unlikely()] Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org
drivers/block/nbd.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index 19f5d5a8b16a..acf3f85bf3c7 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -1388,6 +1388,7 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd, unsigned int cmd, unsigned long arg) { struct nbd_config *config = nbd->config;
loff_t bytesize; switch (cmd) { case NBD_DISCONNECT:@@ -1402,8 +1403,9 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd, case NBD_SET_SIZE: return nbd_set_size(nbd, arg, config->blksize); case NBD_SET_SIZE_BLOCKS:
return nbd_set_size(nbd, arg * config->blksize,config->blksize);
if (check_mul_overflow((loff_t)arg, config->blksize, &bytesize))return -EINVAL;return nbd_set_size(nbd, bytesize, config->blksize); case NBD_SET_TIMEOUT: nbd_set_cmd_timeout(nbd, arg); return 0;arm clang-10, clang-11, clang-12 and clang-13 builds failed. due to this commit on 5.14 and 5.13 on following configs,
- footbridge_defconfig
- mini2440_defconfig
- s3c2410_defconfig
This was already reported on the mailing list.
ERROR: modpost: "__mulodi4" [drivers/block/nbd.ko] undefined! #1438 https://github.com/ClangBuiltLinux/linux/issues/1438
[PATCH 00/10] raise minimum GCC version to 5.1 https://lore.kernel.org/lkml/20210910234047.1019925-1-ndesaulniers@google.co...
linux-next: build failure while building Linus' tree https://lore.kernel.org/all/20210909182525.372ee687@canb.auug.org.au/
Full build log, https://gitlab.com/Linaro/lkft/mirrors/stable/linux-stable-rc/-/jobs/1585407...
Has anyone submitted a fix for this upstream yet? I can't seem to find one :(