user/sven/linux.git/fs/debugfs, branch v5.4.300

new helper: lookup_positive_unlocked()

2023-09-23T08:59:40Z

[ Upstream commit 6c2d4798a8d16cf4f3a28c3cd4af4f1dcbbb4d04 ] Most of the callers of lookup_one_len_unlocked() treat negatives are ERR_PTR(-ENOENT). Provide a helper that would do just that. Note that a pinned positive dentry remains positive - it's ->d_inode is stable, etc.; a pinned _negative_ dentry can become positive at any point as long as you are not holding its parent at least shared. So using lookup_one_len_unlocked() needs to be careful; lookup_positive_unlocked() is safer and that's what the callers end up open-coding anyway. Signed-off-by: Al Viro Stable-dep-of: 0d5a4f8f775f ("fs: Fix error checking for d_hash_and_lookup()") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

debugfs: regset32: Add Runtime PM support

2023-05-17T09:35:32Z

commit 30332eeefec8f83afcea00c360f99ef64b87f220 upstream. Hardware registers of devices under control of power management cannot be accessed at all times. If such a device is suspended, register accesses may lead to undefined behavior, like reading bogus values, or causing exceptions or system lock-ups. Extend struct debugfs_regset32 with an optional field to let device drivers specify the device the registers in the set belong to. This allows debugfs_show_regset32() to make sure the device is resumed while its registers are being read. Signed-off-by: Geert Uytterhoeven Reviewed-by: Niklas Söderlund Reviewed-by: Greg Kroah-Hartman Acked-by: Rafael J. Wysocki Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman

debugfs: fix error when writing negative value to atomic_t debugfs file

2023-01-18T10:40:56Z

[ Upstream commit d472cf797c4e268613dbce5ec9b95d0bcae19ecb ] The simple attribute files do not accept a negative value since the commit 488dac0c9237 ("libfs: fix error cast of negative value in simple_attr_write()"), so we have to use a 64-bit value to write a negative value for a debugfs file created by debugfs_create_atomic_t(). This restores the previous behaviour by introducing DEFINE_DEBUGFS_ATTRIBUTE_SIGNED for a signed value. Link: https://lkml.kernel.org/r/20220919172418.45257-4-akinobu.mita@gmail.com Fixes: 488dac0c9237 ("libfs: fix error cast of negative value in simple_attr_write()") Signed-off-by: Akinobu Mita Reported-by: Zhao Gongyi Reviewed-by: David Hildenbrand Reviewed-by: Greg Kroah-Hartman Cc: Alexander Viro Cc: Jonathan Corbet Cc: Oscar Salvador Cc: Rafael J. Wysocki Cc: Shuah Khan Cc: Wei Yongjun Cc: Yicong Yang Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin

debugfs: add debugfs_lookup_and_remove()

2022-09-15T10:04:54Z

commit dec9b2f1e0455a151a7293c367da22ab973f713e upstream. There is a very common pattern of using debugfs_remove(debufs_lookup(..)) which results in a dentry leak of the dentry that was looked up. Instead of having to open-code the correct pattern of calling dput() on the dentry, create debugfs_lookup_and_remove() to handle this pattern automatically and properly without any memory leaks. Cc: stable Reported-by: Kuyo Chang Tested-by: Kuyo Chang Link: https://lore.kernel.org/r/YxIaQ8cSinDR881k@kroah.com Signed-off-by: Greg Kroah-Hartman

debugfs: lockdown: Allow reading debugfs files that are not world readable

2022-01-27T08:19:36Z

[ Upstream commit 358fcf5ddbec4e6706405847d6a666f5933a6c25 ] When the kernel is locked down the kernel allows reading only debugfs files with mode 444. Mode 400 is also valid but is not allowed. Make the 444 into a mask. Fixes: 5496197f9b08 ("debugfs: Restrict debugfs when the kernel is locked down") Signed-off-by: Michal Suchanek Link: https://lore.kernel.org/r/20220104170505.10248-1-msuchanek@suse.de Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

debugfs: debugfs_create_file_size(): use IS_ERR to check for error

2021-10-06T13:42:35Z

commit af505cad9567f7a500d34bf183696d570d7f6810 upstream. debugfs_create_file() returns encoded error so use IS_ERR for checking return value. Reviewed-by: Christian König Signed-off-by: Nirmoy Das Fixes: ff9fb72bc077 ("debugfs: return error values, not NULL") Cc: stable References: https://gitlab.freedesktop.org/drm/amd/-/issues/1686 Link: https://lore.kernel.org/r/20210902102917.2233-1-nirmoy.das@amd.com Signed-off-by: Greg Kroah-Hartman

debugfs: Return error during {full/open}_proxy_open() on rmmod

2021-09-15T07:47:33Z

[ Upstream commit 112cedc8e600b668688eb809bf11817adec58ddc ] If a kernel module gets unloaded then it printed report about a leak before commit 275678e7a9be ("debugfs: Check module state before warning in {full/open}_proxy_open()"). An additional check was added in this commit to avoid this printing. But it was forgotten that the function must return an error in this case because it was not actually opened. As result, the systems started to crash or to hang when a module was unloaded while something was trying to open a file. Fixes: 275678e7a9be ("debugfs: Check module state before warning in {full/open}_proxy_open()") Cc: Taehee Yoo Reported-by: Mário Lopes Signed-off-by: Sven Eckelmann Link: https://lore.kernel.org/r/20210802162444.7848-1-sven@narfation.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

debugfs: do not attempt to create a new file before the filesystem is initalized

2021-03-04T09:26:10Z

commit 56348560d495d2501e87db559a61de717cd3ab02 upstream. Some subsystems want to add debugfs files at early boot, way before debugfs is initialized. This seems to work somehow as the vfs layer will not allow it to happen, but let's be explicit and test to ensure we are properly up and running before allowing files to be created. Cc: "Rafael J. Wysocki" Cc: stable Reported-by: Michael Walle Reported-by: Marc Zyngier Link: https://lore.kernel.org/r/20210218100818.3622317-2-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

debugfs: be more robust at handling improper input in debugfs_lookup()

2021-03-04T09:26:09Z

commit bc6de804d36b3709d54fa22bd128cbac91c11526 upstream. debugfs_lookup() doesn't like it if it is passed an illegal name pointer, or if the filesystem isn't even initialized yet. If either of these happen, it will crash the system, so fix it up by properly testing for valid input and that we are up and running before trying to find a file in the filesystem. Cc: "Rafael J. Wysocki" Cc: stable Reported-by: Michael Walle Tested-by: Michael Walle Tested-by: Marc Zyngier Link: https://lore.kernel.org/r/20210218100818.3622317-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

debugfs: Fix module state check condition

2020-09-17T11:47:55Z

commit e3b9fc7eec55e6fdc8beeed18f2ed207086341e2 upstream. The '#ifdef MODULE' check in the original commit does not work as intended. The code under the check is not built at all if CONFIG_DEBUG_FS=y. Fix this by using a correct check. Fixes: 275678e7a9be ("debugfs: Check module state before warning in {full/open}_proxy_open()") Signed-off-by: Vladis Dronov Cc: stable Link: https://lore.kernel.org/r/20200811150129.53343-1-vdronov@redhat.com Signed-off-by: Greg Kroah-Hartman