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| author | Akinobu Mita <akinobu.mita@gmail.com> | 2022-09-20 02:24:16 +0900 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2022-11-30 16:13:16 -0800 |
| commit | 2e41f274f9aa71cdcc69dc1f26a3f9304a651804 (patch) | |
| tree | bf50c96c6c6f297b6a21104a2964f594faec39b8 /fs/libfs.c | |
| parent | 7b9cbc7701d562e60ae0836dbad27ea9cf7e0f8d (diff) | |
| download | lwn-2e41f274f9aa71cdcc69dc1f26a3f9304a651804.tar.gz lwn-2e41f274f9aa71cdcc69dc1f26a3f9304a651804.zip | |
libfs: add DEFINE_SIMPLE_ATTRIBUTE_SIGNED for signed value
Patch series "fix error when writing negative value to simple attribute
files".
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()"), but some attribute files want to accept a negative
value.
This patch (of 3):
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.
This adds DEFINE_SIMPLE_ATTRIBUTE_SIGNED for a signed value.
Link: https://lkml.kernel.org/r/20220919172418.45257-1-akinobu.mita@gmail.com
Link: https://lkml.kernel.org/r/20220919172418.45257-2-akinobu.mita@gmail.com
Fixes: 488dac0c9237 ("libfs: fix error cast of negative value in simple_attr_write()")
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Reported-by: Zhao Gongyi <zhaogongyi@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Wei Yongjun <weiyongjun1@huawei.com>
Cc: Yicong Yang <yangyicong@hisilicon.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'fs/libfs.c')
| -rw-r--r-- | fs/libfs.c | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/fs/libfs.c b/fs/libfs.c index 682d56345a1c..aada4e7c8713 100644 --- a/fs/libfs.c +++ b/fs/libfs.c @@ -995,8 +995,8 @@ out: EXPORT_SYMBOL_GPL(simple_attr_read); /* interpret the buffer as a number to call the set function with */ -ssize_t simple_attr_write(struct file *file, const char __user *buf, - size_t len, loff_t *ppos) +static ssize_t simple_attr_write_xsigned(struct file *file, const char __user *buf, + size_t len, loff_t *ppos, bool is_signed) { struct simple_attr *attr; unsigned long long val; @@ -1017,7 +1017,10 @@ ssize_t simple_attr_write(struct file *file, const char __user *buf, goto out; attr->set_buf[size] = '\0'; - ret = kstrtoull(attr->set_buf, 0, &val); + if (is_signed) + ret = kstrtoll(attr->set_buf, 0, &val); + else + ret = kstrtoull(attr->set_buf, 0, &val); if (ret) goto out; ret = attr->set(attr->data, val); @@ -1027,8 +1030,21 @@ out: mutex_unlock(&attr->mutex); return ret; } + +ssize_t simple_attr_write(struct file *file, const char __user *buf, + size_t len, loff_t *ppos) +{ + return simple_attr_write_xsigned(file, buf, len, ppos, false); +} EXPORT_SYMBOL_GPL(simple_attr_write); +ssize_t simple_attr_write_signed(struct file *file, const char __user *buf, + size_t len, loff_t *ppos) +{ + return simple_attr_write_xsigned(file, buf, len, ppos, true); +} +EXPORT_SYMBOL_GPL(simple_attr_write_signed); + /** * generic_fh_to_dentry - generic helper for the fh_to_dentry export operation * @sb: filesystem to do the file handle conversion on |