linux/fs/proc
Josef Bacik 4508943794 proc: use kvzalloc for our kernel buffer
Since

  sysctl: pass kernel pointers to ->proc_handler

we have been pre-allocating a buffer to copy the data from the proc
handlers into, and then copying that to userspace.  The problem is this
just blindly kzalloc()'s the buffer size passed in from the read, which in
the case of our 'cat' binary was 64kib.  Order-4 allocations are not
awesome, and since we can potentially allocate up to our maximum order, so
use kvzalloc for these buffers.

[willy@infradead.org: changelog tweaks]

Link: https://lkml.kernel.org/r/6345270a2c1160b89dd5e6715461f388176899d1.1612972413.git.josef@toxicpanda.com
Fixes: 32927393dc ("sysctl: pass kernel pointers to ->proc_handler")
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
CC: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-26 09:41:03 -08:00
..
array.c proc: provide details on indirect branch speculation 2020-12-15 22:46:15 -08:00
base.c proc/wchan: use printk format instead of lookup_symbol_name() 2021-02-26 09:41:03 -08:00
bootconfig.c proc/bootconfig: Fix to use correct quotes for value 2020-06-16 21:21:03 -04:00
cmdline.c
consoles.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 191 2019-05-30 11:29:21 -07:00
cpuinfo.c proc/cpuinfo: switch to ->read_iter 2020-11-06 10:05:18 -08:00
devices.c block: move block-related definitions out of fs.h 2020-06-24 09:16:02 -06:00
fd.c fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
fd.h fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
generic.c fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
inode.c proc: wire up generic_file_splice_read for iter ops 2020-11-06 10:05:18 -08:00
internal.h fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
interrupts.c
Kconfig treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
kcore.c arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL 2020-12-15 12:13:42 -08:00
kmsg.c proc: faster open/read/close with "permanent" files 2020-04-07 10:43:42 -07:00
loadavg.c
Makefile proc: bootconfig: Add /proc/bootconfig to show boot config list 2020-01-13 13:19:39 -05:00
meminfo.c mm: memcontrol: convert NR_FILE_PMDMAPPED account to pages 2021-02-24 13:38:29 -08:00
namespaces.c Merge branch 'work.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-01-29 11:20:24 -08:00
nommu.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
page.c mm: Add PG_arch_2 page flag 2020-09-04 12:46:06 +01:00
proc_net.c fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
proc_sysctl.c proc: use kvzalloc for our kernel buffer 2021-02-26 09:41:03 -08:00
proc_tty.c
root.c fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
self.c proc: don't allow async path resolution of /proc/thread-self components 2021-02-15 11:02:16 -07:00
softirqs.c
stat.c time-namespace-v5.11 2020-12-14 16:35:39 -08:00
task_mmu.c mm: proc: Invalidate TLB after clearing soft-dirty page state 2021-01-29 20:02:28 +01:00
task_nommu.c mmap locking API: use coccinelle to convert mmap_sem rwsem call sites 2020-06-09 09:39:14 -07:00
thread_self.c proc: don't allow async path resolution of /proc/thread-self components 2021-02-15 11:02:16 -07:00
uptime.c fs/proc: Respect boottime inside time namespace for /proc/uptime 2020-01-14 12:20:56 +01:00
util.c
version.c
vmcore.c vmalloc: remove redundant NULL check 2021-02-24 13:38:30 -08:00