diff options
author | Chaitanya Kulkarni <kch@nvidia.com> | 2022-02-15 13:33:07 -0800 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-04-20 09:06:38 +0200 |
commit | 0e0d0dc27dad0036874d18f712b76ff05a3b89f9 (patch) | |
tree | 3b571a199291beb4614238d0fb18c754f29bb8da | |
parent | 6f7fad6056af08a202cd34e499f214668dae157e (diff) |
loop: use sysfs_emit() in the sysfs xxx show()
[ Upstream commit b27824d31f09ea7b4a6ba2c1b18bd328df3e8bed ]
sprintf does not know the PAGE_SIZE maximum of the temporary buffer
used for outputting sysfs content and it's possible to overrun the
PAGE_SIZE buffer length.
Use a generic sysfs_emit function that knows the size of the
temporary buffer and ensures that no overrun is done for offset
attribute in
loop_attr_[offset|sizelimit|autoclear|partscan|dio]_show() callbacks.
Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Link: https://lore.kernel.org/r/20220215213310.7264-2-kch@nvidia.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
-rw-r--r-- | drivers/block/loop.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/drivers/block/loop.c b/drivers/block/loop.c index f236b7984b94..2ff17b397cd2 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -773,33 +773,33 @@ static ssize_t loop_attr_backing_file_show(struct loop_device *lo, char *buf) static ssize_t loop_attr_offset_show(struct loop_device *lo, char *buf) { - return sprintf(buf, "%llu\n", (unsigned long long)lo->lo_offset); + return sysfs_emit(buf, "%llu\n", (unsigned long long)lo->lo_offset); } static ssize_t loop_attr_sizelimit_show(struct loop_device *lo, char *buf) { - return sprintf(buf, "%llu\n", (unsigned long long)lo->lo_sizelimit); + return sysfs_emit(buf, "%llu\n", (unsigned long long)lo->lo_sizelimit); } static ssize_t loop_attr_autoclear_show(struct loop_device *lo, char *buf) { int autoclear = (lo->lo_flags & LO_FLAGS_AUTOCLEAR); - return sprintf(buf, "%s\n", autoclear ? "1" : "0"); + return sysfs_emit(buf, "%s\n", autoclear ? "1" : "0"); } static ssize_t loop_attr_partscan_show(struct loop_device *lo, char *buf) { int partscan = (lo->lo_flags & LO_FLAGS_PARTSCAN); - return sprintf(buf, "%s\n", partscan ? "1" : "0"); + return sysfs_emit(buf, "%s\n", partscan ? "1" : "0"); } static ssize_t loop_attr_dio_show(struct loop_device *lo, char *buf) { int dio = (lo->lo_flags & LO_FLAGS_DIRECT_IO); - return sprintf(buf, "%s\n", dio ? "1" : "0"); + return sysfs_emit(buf, "%s\n", dio ? "1" : "0"); } LOOP_ATTR_RO(backing_file); |