kernel/linux.git/fs/fat/dir.c, branch v6.12.80

fs: add kernel-doc comments to fat_parse_long()

2024-04-26T04:07:02+00:00

Add kernel-doc style comments with complete parameter descriptions for fat_parse_long(). Link: https://lkml.kernel.org/r/20240322073724.102332-1-yang.lee@linux.alibaba.com Signed-off-by: Yang Li Acked-by: OGAWA Hirofumi Signed-off-by: Andrew Morton

Change calling conventions for filldir_t

2022-08-17T21:25:04+00:00

filldir_t instances (directory iterators callbacks) used to return 0 for "OK, keep going" or -E... for "stop". Note that it's *NOT* how the error values are reported - the rules for those are callback-dependent and ->iterate{,_shared}() instances only care about zero vs. non-zero (look at emit_dir() and friends). So let's just return bool ("should we keep going?") - it's less confusing that way. The choice between "true means keep going" and "true means stop" is bikesheddable; we have two groups of callbacks - do something for everything in directory, until we run into problem and find an entry in directory and do something to it. The former tended to use 0/-E... conventions - -E on failure. The latter tended to use 0/1, 1 being "stop, we are done". The callers treated anything non-zero as "stop", ignoring which non-zero value did they get. "true means stop" would be more natural for the second group; "true means keep going" - for the first one. I tried both variants and the things like if allocation failed something = -ENOMEM; return true; just looked unnatural and asking for trouble. [folded suggestion from Matthew Wilcox ] Acked-by: Christian Brauner (Microsoft) Signed-off-by: Al Viro

fat: use pointer to simple type in put_user()

2022-03-24T02:00:34+00:00

The put_user(val,ptr) macro wants a pointer to a simple type, but in fat_ioctl_filldir() the d_name field references an "array of chars". Be more accurate and explicitly give the pointer to the first character of the d_name[] array. I noticed that issue while trying to optimize the parisc put_user() macro and used an intermediate variable to store the pointer. In that case I got this error: In file included from include/linux/uaccess.h:11, from include/linux/compat.h:17, from fs/fat/dir.c:18: fs/fat/dir.c: In function `fat_ioctl_filldir': fs/fat/dir.c:725:33: error: invalid initializer 725 | if (put_user(0, d2->d_name) || \ | ^~ include/asm/uaccess.h:152:33: note: in definition of macro `__put_user' 152 | __typeof__(ptr) __ptr = ptr; \ | ^~~ fs/fat/dir.c:759:1: note: in expansion of macro `FAT_IOCTL_FILLDIR_FUNC' 759 | FAT_IOCTL_FILLDIR_FUNC(fat_ioctl_filldir, __fat_dirent) Andreas Schwab suggested to use __typeof__(&*(ptr)) __ptr = ptr; instead. This works, but nevertheless it's probably reasonable to fix the original caller too. Link: https://lkml.kernel.org/r/Ygo+A9MREmC1H3kr@p100 Signed-off-by: Helge Deller Acked-by: OGAWA Hirofumi Cc: David Laight Cc: Andreas Schwab Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

treewide: Remove uninitialized_var() usage

2020-07-16T19:35:15+00:00

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

fat_dir_ioctl(): hadn't needed that access_ok() for more than a decade...

2020-05-09T19:57:04+00:00

address is passed only to put_user() and copy_to_user() Signed-off-by: Al Viro

fat: delete an unnecessary check before brelse()

2019-09-26T00:51:40+00:00

brelse() tests whether its argument is NULL and then returns immediately. Thus the test around the call is not needed. This issue was detected by using the Coccinelle software. Link: http://lkml.kernel.org/r/cfff3b81-fb5d-af26-7b5e-724266509045@web.de Signed-off-by: Markus Elfring Acked-by: OGAWA Hirofumi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

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

2019-09-24T22:54:06+00:00

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

treewide: Add SPDX license identifier for missed files

2019-05-21T08:50:45+00:00

Add SPDX license identifiers to all files which: - Have no license information of any form - Have EXPORT_.*_SYMBOL_GPL inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

Merge branch 'akpm' (patches from Andrew)

2019-01-05T17:16:18+00:00

Merge more updates from Andrew Morton: - procfs updates - various misc bits - lib/ updates - epoll updates - autofs - fatfs - a few more MM bits * emailed patches from Andrew Morton : (58 commits) mm/page_io.c: fix polled swap page in checkpatch: add Co-developed-by to signature tags docs: fix Co-Developed-by docs drivers/base/platform.c: kmemleak ignore a known leak fs: don't open code lru_to_page() fs/: remove caller signal_pending branch predictions mm/: remove caller signal_pending branch predictions arch/arc/mm/fault.c: remove caller signal_pending_branch predictions kernel/sched/: remove caller signal_pending branch predictions kernel/locking/mutex.c: remove caller signal_pending branch predictions mm: select HAVE_MOVE_PMD on x86 for faster mremap mm: speed up mremap by 20x on large regions mm: treewide: remove unused address argument from pte_alloc functions initramfs: cleanup incomplete rootfs scripts/gdb: fix lx-version string output kernel/kcov.c: mark write_comp_data() as notrace kernel/sysctl: add panic_print into sysctl panic: add options to print system info when panic happens bfs: extra sanity checking and static inode bitmap exec: separate MM_ANONPAGES and RLIMIT_STACK accounting ...

fat: new inline functions to determine the FAT variant (32, 16 or 12)

2019-01-04T21:13:47+00:00

This patch introduces 3 new inline functions - is_fat12, is_fat16 and is_fat32, and replaces every occurrence in the code in which the FS variant (whether this is FAT12, FAT16 or FAT32) was previously checked using msdos_sb_info->fat_bits. Link: http://lkml.kernel.org/r/1544990640-11604-4-git-send-email-carmeli.tamir@gmail.com Signed-off-by: Carmeli Tamir Acked-by: OGAWA Hirofumi Reviewed-by: Sergey Senozhatsky Cc: Johannes Thumshirn Cc: Bart Van Assche Cc: Martin K. Petersen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds