kernel/git/stable/linux-stable.git/fs/fat, branch linux-4.19.y

fat: fix uninitialized variable

2024-11-08T15:19:19+00:00

commit 963a7f4d3b90ee195b895ca06b95757fcba02d1a upstream. syszbot produced this with a corrupted fs image. In theory, however an IO error would trigger this also. This affects just an error report, so should not be a serious error. Link: https://lkml.kernel.org/r/87r08wjsnh.fsf@mail.parknet.co.jp Link: https://lkml.kernel.org/r/66ff2c95.050a0220.49194.03e9.GAE@google.com Signed-off-by: OGAWA Hirofumi Reported-by: syzbot+ef0d7bc412553291aa86@syzkaller.appspotmail.com Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

fat: fix uninitialized field in nostale filehandles

2024-04-13T10:50:04+00:00

[ Upstream commit fde2497d2bc3a063d8af88b258dbadc86bd7b57c ] When fat_encode_fh_nostale() encodes file handle without a parent it stores only first 10 bytes of the file handle. However the length of the file handle must be a multiple of 4 so the file handle is actually 12 bytes long and the last two bytes remain uninitialized. This is not great at we potentially leak uninitialized information with the handle to userspace. Properly initialize the full handle length. Link: https://lkml.kernel.org/r/20240205122626.13701-1-jack@suse.cz Reported-by: syzbot+3ce5dea5b1539ff36769@syzkaller.appspotmail.com Fixes: ea3983ace6b7 ("fat: restructure export_operations") Signed-off-by: Jan Kara Acked-by: OGAWA Hirofumi Cc: Amir Goldstein Cc: Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin

treewide: Remove uninitialized_var() usage

2023-08-11T09:45:01+00:00

commit 3f649ab728cda8038259d8f14492fe400fbab911 upstream. Using uninitialized_var() is dangerous as it papers over real bugs[1] (or can in the future), and suppresses unrelated compiler warnings (e.g. "unused variable"). If the compiler thinks it is uninitialized, either simply initialize the variable or make compiler changes. In preparation for removing[2] the[3] macro[4], remove all remaining needless uses with the following script: git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \ xargs perl -pi -e \ 's/\buninitialized_var$([^$]+)\)/\1/g; s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;' drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid pathological white-space. No outstanding warnings were found building allmodconfig with GCC 9.3.0 for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64, alpha, and m68k. [1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/ [2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/ [3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/ [4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/ Reviewed-by: Leon Romanovsky # drivers/infiniband and mlx4/mlx5 Acked-by: Jason Gunthorpe # IB Acked-by: Kalle Valo # wireless drivers Reviewed-by: Chao Yu # erofs Signed-off-by: Kees Cook Signed-off-by: Greg Kroah-Hartman

fat: add ratelimit to fat*_ent_bread()

2022-06-14T14:59:18+00:00

[ Upstream commit 183c3237c928109d2008c0456dff508baf692b20 ] fat*_ent_bread() can be the cause of too many report on I/O error path. So use fat_msg_ratelimit() instead. Link: https://lkml.kernel.org/r/87bkxogfeq.fsf@mail.parknet.co.jp Signed-off-by: OGAWA Hirofumi Reported-by: qianfan Tested-by: qianfan Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin

fat: don't allow to mount if the FAT length == 0

2020-06-22T07:05:08+00:00

commit b1b65750b8db67834482f758fc385bfa7560d228 upstream. If FAT length == 0, the image doesn't have any data. And it can be the cause of overlapping the root dir and FAT entries. Also Windows treats it as invalid format. Reported-by: syzbot+6f1624f937d9d6911e2d@syzkaller.appspotmail.com Signed-off-by: OGAWA Hirofumi Signed-off-by: Andrew Morton Cc: Marco Elver Cc: Dmitry Vyukov Link: http://lkml.kernel.org/r/87r1wz8mrd.fsf@mail.parknet.co.jp Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

fat: fix uninit-memory access for partial initialized inode

2020-03-11T13:15:01+00:00

commit bc87302a093f0eab45cd4e250c2021299f712ec6 upstream. When get an error in the middle of reading an inode, some fields in the inode might be still not initialized. And then the evict_inode path may access those fields via iput(). To fix, this makes sure that inode fields are initialized. Reported-by: syzbot+9d82b8de2992579da5d0@syzkaller.appspotmail.com Signed-off-by: Andrew Morton Signed-off-by: OGAWA Hirofumi Cc: Link: http://lkml.kernel.org/r/871rqnreqx.fsf@mail.parknet.co.jp Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

fat: work around race with userspace's read via blockdev while mounting

2019-10-07T16:57:14+00:00

[ Upstream commit 07bfa4415ab607e459b69bd86aa7e7602ce10b4f ] If userspace reads the buffer via blockdev while mounting, sb_getblk()+modify can race with buffer read via blockdev. For example, FS userspace bh = sb_getblk() modify bh->b_data read ll_rw_block(bh) fill bh->b_data by on-disk data /* lost modified data by FS */ set_buffer_uptodate(bh) set_buffer_uptodate(bh) Userspace should not use the blockdev while mounting though, the udev seems to be already doing this. Although I think the udev should try to avoid this, workaround the race by small overhead. Link: http://lkml.kernel.org/r/87pnk7l3sw.fsf_-_@mail.parknet.co.jp Signed-off-by: OGAWA Hirofumi Reported-by: Jan Stancek Tested-by: Jan Stancek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

fs/fat/file.c: issue flush after the writeback of FAT

2019-06-15T09:53:59+00:00

[ Upstream commit bd8309de0d60838eef6fb575b0c4c7e95841cf73 ] fsync() needs to make sure the data & meta-data of file are persistent after the return of fsync(), even when a power-failure occurs later. In the case of fat-fs, the FAT belongs to the meta-data of file, so we need to issue a flush after the writeback of FAT instead before. Also bail out early when any stage of fsync fails. Link: http://lkml.kernel.org/r/20190409030158.136316-1-houtao1@huawei.com Signed-off-by: Hou Tao Acked-by: OGAWA Hirofumi Cc: Al Viro Cc: Jan Kara Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

fs/fat/fatent.c: add cond_resched() to fat_count_free_clusters()

2018-10-13T07:31:03+00:00

On non-preempt kernels this loop can take a long time (more than 50 ticks) processing through entries. Link: http://lkml.kernel.org/r/20181010172623.57033-1-khazhy@google.com Signed-off-by: Khazhismel Kumykov Acked-by: OGAWA Hirofumi Reviewed-by: Andrew Morton Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

fat: propagate 64-bit inode timestamps

2018-08-22T17:52:50+00:00

Now that we pass down 64-bit timestamps from VFS, we just need to convert that correctly into on-disk timestamps. To make that work correctly, this changes the last use of time_to_tm() in the kernel to time64_to_tm(), which also lets use remove that deprecated interfaces. Similarly, the time_t use in fat_time_fat2unix() truncates the timestamp on the way in, which can be avoided by using types that are wide enough to hold the intermediate values during the conversion. [hirofumi@mail.parknet.co.jp: remove useless temporary variable, needless long long] Link: http://lkml.kernel.org/r/20180619153646.3637529-1-arnd@arndb.de Signed-off-by: Arnd Bergmann Acked-by: OGAWA Hirofumi Cc: Jeff Layton Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds