The patch titled
Subject: libfs: fix error cast of negative value in simple_attr_write()
has been added to the -mm tree. Its filename is
libfs-fix-error-cast-of-negative-value-in-simple_attr_write.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/libfs-fix-error-cast-of-negative-value-in-simple_attr_write.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/libfs-fix-error-cast-of-negative-value-in-simple_attr_write.patch
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------------------------------------------------------
From: Yicong Yang <yangyicong@xxxxxxxxxxxxx>
Subject: libfs: fix error cast of negative value in simple_attr_write()
The attr->set() receive a value of u64, but simple_strtoll() is used
for doing the conversion. It will lead to the error cast if user inputs
a negative value.
Use kstrtoull() instead of simple_strtoll() to convert a string got
from the user to an unsigned value. The former will return '-EINVAL' if
it gets a negetive value, but the latter can't handle the situation
correctly.
Link: https://lkml.kernel.org/r/1605000324-7428-1-git-send-email-yangyicong@xxxxxxxxxxxxx
Fixes: f7b88631a897 ("fs/libfs.c: fix simple_attr_write() on 32bit machines")
Signed-off-by: Yicong Yang <yangyicong@xxxxxxxxxxxxx>
Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/libfs.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/fs/libfs.c~libfs-fix-error-cast-of-negative-value-in-simple_attr_write
+++ a/fs/libfs.c
@@ -977,7 +977,9 @@ ssize_t simple_attr_write(struct file *f
goto out;
attr->set_buf[size] = '\0';
- val = simple_strtoll(attr->set_buf, NULL, 0);
+ ret = kstrtoull(attr->set_buf, 0, &val);
+ if (ret)
+ goto out;
ret = attr->set(attr->data, val);
if (ret == 0)
ret = len; /* on success, claim we got the whole input */
_
Patches currently in -mm which might be from yangyicong@xxxxxxxxxxxxx are
libfs-fix-error-cast-of-negative-value-in-simple_attr_write.patch
