Eric Biggers 8bbd6c83e1 fs: sysfs_emit_at: Remove PAGE_SIZE alignment check ... From: Eric Biggers <ebiggers@google.com> [No upstream commit because this fixes a bug in a backport.] Before upstream commit 59bb47985c ("mm, sl[aou]b: guarantee natural alignment for kmalloc(power-of-two)") which went into v5.4, kmalloc did *not* always guarantee that PAGE_SIZE allocations are PAGE_SIZE-aligned. Upstream commit 2efc459d06 ("sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs output") added two WARN()s that trigger when PAGE_SIZE allocations are not PAGE_SIZE-aligned. This was backported to old kernels that don't guarantee PAGE_SIZE alignment. Commit 10ddfb4952 ("fs: sysfs_emit: Remove PAGE_SIZE alignment check") in 4.19.y, and its equivalent in 4.14.y and 4.9.y, tried to fix this bug. However, only it handled sysfs_emit(), not sysfs_emit_at(). Fix it in sysfs_emit_at() too. A reproducer is to build the kernel with the following options: CONFIG_SLUB=y CONFIG_SLUB_DEBUG=y CONFIG_SLUB_DEBUG_ON=y CONFIG_PM=y CONFIG_SUSPEND=y CONFIG_PM_WAKELOCKS=y Then run: echo foo > /sys/power/wake_lock && cat /sys/power/wake_lock Fixes: cb1f69d53a ("sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs output") Reported-by: kernel test robot <yujie.liu@intel.com> Link: https://lore.kernel.org/r/202303141634.1e64fd76-yujie.liu@intel.com Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2023-03-22 13:26:13 +01:00
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Kconfig	…
Makefile	…
dir.c	kernfs: make kernfs_path*() behave in the style of strlcpy()	2016-08-10 11:23:44 -04:00
file.c	fs: sysfs_emit_at: Remove PAGE_SIZE alignment check	2023-03-22 13:26:13 +01:00
group.c	sysfs print name of undiscoverable attribute group	2016-09-27 12:24:29 +02:00
mount.c	unfuck sysfs_mount()	2021-06-30 08:48:55 -04:00
symlink.c	sysfs: symlink: export sysfs_create_link_nowarn()	2018-03-31 18:10:38 +02:00
sysfs.h	…