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| author | Joe Perches <joe@perches.com> | 2020-09-16 13:40:38 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-03-07 11:27:45 +0100 |
| commit | 390881843b4f13bcac8d58dcf1ebcc34e0deffea (patch) | |
| tree | de7447b67200e144c2aa30740c7dd0c588b953b5 /include | |
| parent | 6c6711c1a0cd2675f9c537c96bd70ecdd84c5d3e (diff) | |
| download | linux-390881843b4f13bcac8d58dcf1ebcc34e0deffea.tar.gz linux-390881843b4f13bcac8d58dcf1ebcc34e0deffea.tar.bz2 linux-390881843b4f13bcac8d58dcf1ebcc34e0deffea.zip | |
sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs output
commit 2efc459d06f1630001e3984854848a5647086232 upstream.
Output defects can exist in sysfs content using sprintf and snprintf.
sprintf does not know the PAGE_SIZE maximum of the temporary buffer
used for outputting sysfs content and it's possible to overrun the
PAGE_SIZE buffer length.
Add a generic sysfs_emit function that knows that the size of the
temporary buffer and ensures that no overrun is done.
Add a generic sysfs_emit_at function that can be used in multiple
call situations that also ensures that no overrun is done.
Validate the output buffer argument to be page aligned.
Validate the offset len argument to be within the PAGE_SIZE buf.
Signed-off-by: Joe Perches <joe@perches.com>
Link: https://lore.kernel.org/r/884235202216d464d61ee975f7465332c86f76b2.1600285923.git.joe@perches.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/sysfs.h | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index cca19bb200bd..d19211a4502b 100644 --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -301,6 +301,11 @@ static inline void sysfs_enable_ns(struct kernfs_node *kn) return kernfs_enable_ns(kn); } +__printf(2, 3) +int sysfs_emit(char *buf, const char *fmt, ...); +__printf(3, 4) +int sysfs_emit_at(char *buf, int at, const char *fmt, ...); + #else /* CONFIG_SYSFS */ static inline int sysfs_create_dir_ns(struct kobject *kobj, const void *ns) @@ -507,6 +512,17 @@ static inline void sysfs_enable_ns(struct kernfs_node *kn) { } +__printf(2, 3) +static inline int sysfs_emit(char *buf, const char *fmt, ...) +{ + return 0; +} + +__printf(3, 4) +static inline int sysfs_emit_at(char *buf, int at, const char *fmt, ...) +{ + return 0; +} #endif /* CONFIG_SYSFS */ static inline int __must_check sysfs_create_file(struct kobject *kobj, |