From 034dd340b08be1f2f0477ad16131d609f9dbd53c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 30 Aug 2026 09:22:00 -0700 Subject: Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure --- fs/exfat/misc.c | 207 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 207 insertions(+) create mode 100644 fs/exfat/misc.c (limited to 'fs/exfat/misc.c') diff --git a/fs/exfat/misc.c b/fs/exfat/misc.c new file mode 100644 index 000000000..6f11a96a4 --- /dev/null +++ b/fs/exfat/misc.c @@ -0,0 +1,207 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Written 1992,1993 by Werner Almesberger + * 22/11/2000 - Fixed fat_date_unix2dos for dates earlier than 01/01/1980 + * and date_dos2unix for date==0 by Igor Zhbanov(bsg@uniyar.ac.ru) + * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd. + */ + +#include +#include +#include +#include +#include + +#include "exfat_raw.h" +#include "exfat_fs.h" + +/* + * exfat_fs_error reports a file system problem that might indicate fa data + * corruption/inconsistency. Depending on 'errors' mount option the + * panic() is called, or error message is printed FAT and nothing is done, + * or filesystem is remounted read-only (default behavior). + * In case the file system is remounted read-only, it can be made writable + * again by remounting it. + */ +void __exfat_fs_error(struct super_block *sb, int report, const char *fmt, ...) +{ + struct exfat_mount_options *opts = &EXFAT_SB(sb)->options; + va_list args; + struct va_format vaf; + + if (report) { + va_start(args, fmt); + vaf.fmt = fmt; + vaf.va = &args; + exfat_err(sb, "error, %pV", &vaf); + va_end(args); + } + + if (opts->errors == EXFAT_ERRORS_PANIC) { + panic("exFAT-fs (%s): fs panic from previous error\n", + sb->s_id); + } else if (opts->errors == EXFAT_ERRORS_RO && !sb_rdonly(sb)) { + sb->s_flags |= SB_RDONLY; + exfat_err(sb, "Filesystem has been set read-only"); + } +} + +#define SECS_PER_MIN (60) +#define TIMEZONE_SEC(x) ((x) * 15 * SECS_PER_MIN) + +static void exfat_adjust_tz(struct timespec64 *ts, u8 tz_off) +{ + if (tz_off <= 0x3F) + ts->tv_sec -= TIMEZONE_SEC(tz_off); + else /* 0x40 <= (tz_off & 0x7F) <=0x7F */ + ts->tv_sec += TIMEZONE_SEC(0x80 - tz_off); +} + +static inline int exfat_tz_offset(struct exfat_sb_info *sbi) +{ + if (sbi->options.sys_tz) + return -sys_tz.tz_minuteswest; + return sbi->options.time_offset; +} + +/* Convert a EXFAT time/date pair to a UNIX date (seconds since 1 1 70). */ +void exfat_get_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts, + u8 tz, __le16 time, __le16 date, u8 time_cs) +{ + u16 t = le16_to_cpu(time); + u16 d = le16_to_cpu(date); + + ts->tv_sec = mktime64(1980 + (d >> 9), d >> 5 & 0x000F, d & 0x001F, + t >> 11, (t >> 5) & 0x003F, (t & 0x001F) << 1); + + + /* time_cs field represent 0 ~ 199cs(1990 ms) */ + if (time_cs) { + ts->tv_sec += time_cs / 100; + ts->tv_nsec = (time_cs % 100) * 10 * NSEC_PER_MSEC; + } else + ts->tv_nsec = 0; + + if (tz & EXFAT_TZ_VALID) + /* Adjust timezone to UTC0. */ + exfat_adjust_tz(ts, tz & ~EXFAT_TZ_VALID); + else + ts->tv_sec -= exfat_tz_offset(sbi) * SECS_PER_MIN; +} + +/* Convert linear UNIX date to a EXFAT time/date pair. */ +void exfat_set_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts, + u8 *tz, __le16 *time, __le16 *date, u8 *time_cs) +{ + struct tm tm; + u16 t, d; + + time64_to_tm(ts->tv_sec, 0, &tm); + t = (tm.tm_hour << 11) | (tm.tm_min << 5) | (tm.tm_sec >> 1); + d = ((tm.tm_year - 80) << 9) | ((tm.tm_mon + 1) << 5) | tm.tm_mday; + + *time = cpu_to_le16(t); + *date = cpu_to_le16(d); + + /* time_cs field represent 0 ~ 199cs(1990 ms) */ + if (time_cs) + *time_cs = (tm.tm_sec & 1) * 100 + + ts->tv_nsec / (10 * NSEC_PER_MSEC); + + /* + * Record 00h value for OffsetFromUtc field and 1 value for OffsetValid + * to indicate that local time and UTC are the same. + */ + *tz = EXFAT_TZ_VALID; +} + +/* + * The timestamp for access_time has double seconds granularity. + * (There is no 10msIncrement field for access_time unlike create/modify_time) + * atime also has only a 2-second resolution. + */ +void exfat_truncate_atime(struct timespec64 *ts) +{ + ts->tv_sec = round_down(ts->tv_sec, 2); + ts->tv_nsec = 0; +} + +void exfat_truncate_inode_atime(struct inode *inode) +{ + struct timespec64 atime = inode_get_atime(inode); + + exfat_truncate_atime(&atime); + inode_set_atime_to_ts(inode, atime); +} + +u16 exfat_calc_chksum16(void *data, int len, u16 chksum, int type) +{ + int i; + u8 *c = (u8 *)data; + + for (i = 0; i < len; i++, c++) { + if (unlikely(type == CS_DIR_ENTRY && (i == 2 || i == 3))) + continue; + chksum = ((chksum << 15) | (chksum >> 1)) + *c; + } + return chksum; +} + +u32 exfat_calc_chksum32(void *data, int len, u32 chksum, int type) +{ + int i; + u8 *c = (u8 *)data; + + for (i = 0; i < len; i++, c++) { + if (unlikely(type == CS_BOOT_SECTOR && + (i == 106 || i == 107 || i == 112))) + continue; + chksum = ((chksum << 31) | (chksum >> 1)) + *c; + } + return chksum; +} + +int exfat_update_bh(struct buffer_head *bh, int sync) +{ + int err = 0; + + set_buffer_uptodate(bh); + mark_buffer_dirty(bh); + + if (sync) + err = sync_dirty_buffer(bh); + + return err; +} + +int exfat_update_bhs(struct buffer_head **bhs, int nr_bhs, int sync) +{ + int i, err = 0; + + for (i = 0; i < nr_bhs; i++) { + set_buffer_uptodate(bhs[i]); + mark_buffer_dirty(bhs[i]); + if (sync) + write_dirty_buffer(bhs[i], REQ_SYNC); + } + + for (i = 0; i < nr_bhs && sync; i++) { + wait_on_buffer(bhs[i]); + if (!err && !buffer_uptodate(bhs[i])) + err = -EIO; + } + return err; +} + +void exfat_chain_set(struct exfat_chain *ec, unsigned int dir, + unsigned int size, unsigned char flags) +{ + ec->dir = dir; + ec->size = size; + ec->flags = flags; +} + +void exfat_chain_dup(struct exfat_chain *dup, struct exfat_chain *ec) +{ + return exfat_chain_set(dup, ec->dir, ec->size, ec->flags); +} -- cgit v1.3.1