user/sven/linux.git/kernel/acct.c, branch v6.16.2

acct: block access to kernel internal filesystems

2025-02-12T11:24:16Z

There's no point in allowing anything kernel internal nor procfs or sysfs. Link: https://lore.kernel.org/r/20250127091811.3183623-1-quzicheng@huawei.com Link: https://lore.kernel.org/r/20250211-work-acct-v1-2-1c16aecab8b3@kernel.org Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reviewed-by: Amir Goldstein Reported-by: Zicheng Qu Cc: stable@vger.kernel.org Signed-off-by: Christian Brauner

acct: perform last write from workqueue

2025-02-12T11:24:16Z

In [1] it was reported that the acct(2) system call can be used to trigger NULL deref in cases where it is set to write to a file that triggers an internal lookup. This can e.g., happen when pointing acc(2) to /sys/power/resume. At the point the where the write to this file happens the calling task has already exited and called exit_fs(). A lookup will thus trigger a NULL-deref when accessing current->fs. Reorganize the code so that the the final write happens from the workqueue but with the caller's credentials. This preserves the (strange) permission model and has almost no regression risk. This api should stop to exist though. Link: https://lore.kernel.org/r/20250127091811.3183623-1-quzicheng@huawei.com [1] Link: https://lore.kernel.org/r/20250211-work-acct-v1-1-1c16aecab8b3@kernel.org Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: Zicheng Qu Cc: stable@vger.kernel.org Signed-off-by: Christian Brauner

treewide: const qualify ctl_tables where applicable

2025-01-28T12:48:37Z

Add the const qualifier to all the ctl_tables in the tree except for watchdog_hardlockup_sysctl, memory_allocation_profiling_sysctls, loadpin_sysctl_table and the ones calling register_net_sysctl (./net, drivers/inifiniband dirs). These are special cases as they use a registration function with a non-const qualified ctl_table argument or modify the arrays before passing them on to the registration function. Constifying ctl_table structs will prevent the modification of proc_handler function pointers as the arrays would reside in .rodata. This is made possible after commit 78eb4ea25cd5 ("sysctl: treewide: constify the ctl_table argument of proc_handlers") constified all the proc_handlers. Created this by running an spatch followed by a sed command: Spatch: virtual patch @ depends on !(file in "net") disable optional_qualifier @ identifier table_name != { watchdog_hardlockup_sysctl, iwcm_ctl_table, ucma_ctl_table, memory_allocation_profiling_sysctls, loadpin_sysctl_table }; @@ + const struct ctl_table table_name [] = { ... }; sed: sed --in-place \ -e "s/struct ctl_table .table = &uts_kern/const struct ctl_table *table = \&uts_kern/" \ kernel/utsname_sysctl.c Reviewed-by: Song Liu Acked-by: Steven Rostedt (Google) # for kernel/trace/ Reviewed-by: Martin K. Petersen # SCSI Reviewed-by: Darrick J. Wong # xfs Acked-by: Jani Nikula Acked-by: Corey Minyard Acked-by: Wei Liu Acked-by: Thomas Gleixner Reviewed-by: Bill O'Donnell Acked-by: Baoquan He Acked-by: Ashutosh Dixit Acked-by: Anna Schumaker Signed-off-by: Joel Granados

kernel misc: Remove the now superfluous sentinel elements from ctl_table array

2024-04-24T07:43:53Z

This commit comes at the tail end of a greater effort to remove the empty elements at the end of the ctl_table arrays (sentinels) which will reduce the overall build time size of the kernel and run time memory bloat by ~64 bytes per sentinel (further information Link : https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) Remove the sentinel from ctl_table arrays. Reduce by one the values used to compare the size of the adjusted arrays. Signed-off-by: Joel Granados

fs: rename __mnt_{want,drop}_write*() helpers

2023-09-11T13:05:50Z

Before exporting these helpers to modules, make their names more meaningful. The names mnt_{get,put)_write_access*() were chosen, because they rhyme with the inode {get,put)_write_access() helpers, which have a very close meaning for the inode object. Suggested-by: Christian Brauner Link: https://lore.kernel.org/r/20230817-anfechtbar-ruhelosigkeit-8c6cca8443fc@brauner/ Signed-off-by: Amir Goldstein Message-Id: <20230908132900.2983519-2-amir73il@gmail.com> Signed-off-by: Christian Brauner

Merge tag 'audit-pr-20230829' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit

2023-08-30T15:17:35Z

Pull audit updates from Paul Moore: "Six audit patches, the highlights are: - Add an explicit cond_resched() call when generating PATH records Certain tracefs/debugfs operations can generate a *lot* of audit PATH entries and if one has an aggressive system configuration (not the default) this can cause a soft lockup in the audit code as it works to process all of these new entries. This is in sharp contrast to the common case where only one or two PATH entries are logged. In order to fix this corner case without excessively impacting the common case we're adding a single cond_rescued() call between two of the most intensive loops in the __audit_inode_child() function. - Various minor cleanups We removed a conditional header file as the included header already had the necessary logic in place, fixed a dummy function's return value, and the usual collection of checkpatch.pl noise (whitespace, brace, and trailing statement tweaks)" * tag 'audit-pr-20230829' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit: audit: move trailing statements to next line audit: cleanup function braces and assignment-in-if-condition audit: add space before parenthesis and around '=', "==", and '<' audit: fix possible soft lockup in __audit_inode_child() audit: correct audit_filter_inodes() definition audit: include security.h unconditionally

acct: replace all non-returning strlcpy with strscpy

2023-08-18T17:18:51Z

strlcpy() reads the entire source buffer first. This read may exceed the destination size limit. This is both inefficient and can lead to linear read overflows if a source string is not NUL-terminated [1]. In an effort to remove strlcpy() completely [2], replace strlcpy() here with strscpy(). No return values were used, so direct replacement is safe. [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy [2] https://github.com/KSPP/linux/issues/89 Link: https://lkml.kernel.org/r/20230710011748.3538624-1-azeemshaikh38@gmail.com Signed-off-by: Azeem Shaikh Cc: Kees Cook Signed-off-by: Andrew Morton

audit: add space before parenthesis and around '=', "==", and '<'

2023-08-15T22:09:20Z

Fixes following checkpatch.pl issue: ERROR: space required before the open parenthesis '(' ERROR: spaces required around that '=' ERROR: spaces required around that '<' ERROR: spaces required around that '==' Signed-off-by: Atul Kumar Pant [PM: subject line tweaks] Signed-off-by: Paul Moore

acct: fix potential integer overflow in encode_comp_t()

2022-12-01T00:13:18Z

The integer overflow is descripted with following codes: > 317 static comp_t encode_comp_t(u64 value) > 318 { > 319 int exp, rnd; ...... > 341 exp <<= MANTSIZE; > 342 exp += value; > 343 return exp; > 344 } Currently comp_t is defined as type of '__u16', but the variable 'exp' is type of 'int', so overflow would happen when variable 'exp' in line 343 is greater than 65535. Link: https://lkml.kernel.org/r/20210515140631.369106-3-zhengyejian1@huawei.com Signed-off-by: Zheng Yejian Cc: Hanjun Guo Cc: Randy Dunlap Cc: Vlastimil Babka Cc: Zhang Jinhao Signed-off-by: Andrew Morton

acct: fix accuracy loss for input value of encode_comp_t()

2022-12-01T00:13:18Z

Patch series "Fix encode_comp_t()". Type conversion in encode_comp_t() may look a bit problematic. This patch (of 2): See calculation of ac_{u,s}time in fill_ac(): > ac->ac_utime = encode_comp_t(nsec_to_AHZ(pacct->ac_utime)); > ac->ac_stime = encode_comp_t(nsec_to_AHZ(pacct->ac_stime)); Return value of nsec_to_AHZ() is always type of 'u64', but it is handled as type of 'unsigned long' in encode_comp_t, and accuracy loss would happen on 32-bit platform when 'unsigned long' value is 32-bit-width. So 'u64' value of encode_comp_t() may look better. Link: https://lkml.kernel.org/r/20210515140631.369106-1-zhengyejian1@huawei.com Link: https://lkml.kernel.org/r/20210515140631.369106-2-zhengyejian1@huawei.com Signed-off-by: Zheng Yejian Cc: Hanjun Guo Cc: Randy Dunlap # build-tested Cc: Vlastimil Babka Cc: Zhang Jinhao Signed-off-by: Andrew Morton