2022-10-04 23:26:40

by Nathan Chancellor

Subject: [PATCH -next v2 1/2] fs/ntfs3: Don't use uni1 uninitialized in ntfs_d_compare()

Clang warns:

fs/ntfs3/namei.c:445:7: error: variable 'uni1' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
if (toupper(c1) != toupper(c2)) {
^~~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/ctype.h:64:20: note: expanded from macro 'toupper'
#define toupper(c) __toupper(c)
^
fs/ntfs3/namei.c:487:12: note: uninitialized use occurs here
__putname(uni1);
^~~~
./include/linux/fs.h:2789:65: note: expanded from macro '__putname'
#define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
^~~~
fs/ntfs3/namei.c:445:3: note: remove the 'if' if its condition is always false
if (toupper(c1) != toupper(c2)) {
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
fs/ntfs3/namei.c:434:7: error: variable 'uni1' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
if (!lm--) {
^~~~~
fs/ntfs3/namei.c:487:12: note: uninitialized use occurs here
__putname(uni1);
^~~~
./include/linux/fs.h:2789:65: note: expanded from macro '__putname'
#define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
^~~~
fs/ntfs3/namei.c:434:3: note: remove the 'if' if its condition is always false
if (!lm--) {
^~~~~~~~~~~~
fs/ntfs3/namei.c:430:22: note: initialize the variable 'uni1' to silence this warning
struct cpu_str *uni1, *uni2;
^
= NULL
2 errors generated.

There is no point in calling __putname() in these particular error
paths, as there has been no corresponding __getname() call yet. Just
return directly in these blocks to clear up the warning.

Fixes: a3a956c78efa ("fs/ntfs3: Add option "nocase"")
Link: https://github.com/ClangBuiltLinux/linux/issues/1729
Reviewed-by: Nick Desaulniers <[email protected]>
Signed-off-by: Nathan Chancellor <[email protected]>
---

v2:
* Pick up Nick's reviewed-by tag.
v1: https://lore.kernel.org/[email protected]/

fs/ntfs3/namei.c | 12 ++++--------
1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/fs/ntfs3/namei.c b/fs/ntfs3/namei.c
index 315763eb05ff..5d3a6ce3f05f 100644
--- a/fs/ntfs3/namei.c
+++ b/fs/ntfs3/namei.c
@@ -431,10 +431,8 @@ static int ntfs_d_compare(const struct dentry *dentry, unsigned int len1,

/* First try fast implementation. */
for (;;) {
- if (!lm--) {
- ret = len1 == len2 ? 0 : 1;
- goto out;
- }
+ if (!lm--)
+ return len1 == len2 ? 0 : 1;

if ((c1 = *n1++) == (c2 = *n2++))
continue;
@@ -442,10 +440,8 @@ static int ntfs_d_compare(const struct dentry *dentry, unsigned int len1,
if (c1 >= 0x80 || c2 >= 0x80)
break;

- if (toupper(c1) != toupper(c2)) {
- ret = 1;
- goto out;
- }
+ if (toupper(c1) != toupper(c2))
+ return 1;
}

/*

base-commit: d45da67caedacd500879de5e649360cc70777af7
--
2.37.3

2022-10-04 23:27:29

by Nathan Chancellor

Subject: [PATCH -next v2 2/2] fs/ntfs3: Eliminate unnecessary ternary operator in ntfs_d_compare()

'a == b ? 0 : 1' is logically equivalent to 'a != b'.

Suggested-by: Nick Desaulniers <[email protected]>
Signed-off-by: Nathan Chancellor <[email protected]>
---

v2: New patch.

fs/ntfs3/namei.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/ntfs3/namei.c b/fs/ntfs3/namei.c
index 5d3a6ce3f05f..6b0d2c01d6ff 100644
--- a/fs/ntfs3/namei.c
+++ b/fs/ntfs3/namei.c
@@ -432,7 +432,7 @@ static int ntfs_d_compare(const struct dentry *dentry, unsigned int len1,
/* First try fast implementation. */
for (;;) {
if (!lm--)
- return len1 == len2 ? 0 : 1;
+ return len1 != len2;

if ((c1 = *n1++) == (c2 = *n2++))
continue;
--
2.37.3

2022-10-04 23:45:24

by Nick Desaulniers

Subject: Re: [PATCH -next v2 2/2] fs/ntfs3: Eliminate unnecessary ternary operator in ntfs_d_compare()

On Tue, Oct 4, 2022 at 4:24 PM Nathan Chancellor <[email protected]> wrote:
>
> 'a == b ? 0 : 1' is logically equivalent to 'a != b'.
>
> Suggested-by: Nick Desaulniers <[email protected]>
> Signed-off-by: Nathan Chancellor <[email protected]>

Thanks for the patch!
Reviewed-by: Nick Desaulniers <[email protected]>

> ---
>
> v2: New patch.
>
> fs/ntfs3/namei.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/ntfs3/namei.c b/fs/ntfs3/namei.c
> index 5d3a6ce3f05f..6b0d2c01d6ff 100644
> --- a/fs/ntfs3/namei.c
> +++ b/fs/ntfs3/namei.c
> @@ -432,7 +432,7 @@ static int ntfs_d_compare(const struct dentry *dentry, unsigned int len1,
> /* First try fast implementation. */
> for (;;) {
> if (!lm--)
> - return len1 == len2 ? 0 : 1;
> + return len1 != len2;
>
> if ((c1 = *n1++) == (c2 = *n2++))
> continue;
> --
> 2.37.3
>


--
Thanks,
~Nick Desaulniers

2022-10-21 17:35:54

by Nathan Chancellor

Subject: Re: [PATCH -next v2 1/2] fs/ntfs3: Don't use uni1 uninitialized in ntfs_d_compare()

Ping? This is still breaking our builds in -next...

On Tue, Oct 04, 2022 at 04:23:58PM -0700, Nathan Chancellor wrote:
> Clang warns:
>
> fs/ntfs3/namei.c:445:7: error: variable 'uni1' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
> if (toupper(c1) != toupper(c2)) {
> ^~~~~~~~~~~~~~~~~~~~~~~~~~
> ./include/linux/ctype.h:64:20: note: expanded from macro 'toupper'
> #define toupper(c) __toupper(c)
> ^
> fs/ntfs3/namei.c:487:12: note: uninitialized use occurs here
> __putname(uni1);
> ^~~~
> ./include/linux/fs.h:2789:65: note: expanded from macro '__putname'
> #define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
> ^~~~
> fs/ntfs3/namei.c:445:3: note: remove the 'if' if its condition is always false
> if (toupper(c1) != toupper(c2)) {
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> fs/ntfs3/namei.c:434:7: error: variable 'uni1' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
> if (!lm--) {
> ^~~~~
> fs/ntfs3/namei.c:487:12: note: uninitialized use occurs here
> __putname(uni1);
> ^~~~
> ./include/linux/fs.h:2789:65: note: expanded from macro '__putname'
> #define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
> ^~~~
> fs/ntfs3/namei.c:434:3: note: remove the 'if' if its condition is always false
> if (!lm--) {
> ^~~~~~~~~~~~
> fs/ntfs3/namei.c:430:22: note: initialize the variable 'uni1' to silence this warning
> struct cpu_str *uni1, *uni2;
> ^
> = NULL
> 2 errors generated.
>
> There is no point in calling __putname() in these particular error
> paths, as there has been no corresponding __getname() call yet. Just
> return directly in these blocks to clear up the warning.
>
> Fixes: a3a956c78efa ("fs/ntfs3: Add option "nocase"")
> Link: https://github.com/ClangBuiltLinux/linux/issues/1729
> Reviewed-by: Nick Desaulniers <[email protected]>
> Signed-off-by: Nathan Chancellor <[email protected]>
> ---
>
> v2:
> * Pick up Nick's reviewed-by tag.
> v1: https://lore.kernel.org/[email protected]/
>
> fs/ntfs3/namei.c | 12 ++++--------
> 1 file changed, 4 insertions(+), 8 deletions(-)
>
> diff --git a/fs/ntfs3/namei.c b/fs/ntfs3/namei.c
> index 315763eb05ff..5d3a6ce3f05f 100644
> --- a/fs/ntfs3/namei.c
> +++ b/fs/ntfs3/namei.c
> @@ -431,10 +431,8 @@ static int ntfs_d_compare(const struct dentry *dentry, unsigned int len1,
>
> /* First try fast implementation. */
> for (;;) {
> - if (!lm--) {
> - ret = len1 == len2 ? 0 : 1;
> - goto out;
> - }
> + if (!lm--)
> + return len1 == len2 ? 0 : 1;
>
> if ((c1 = *n1++) == (c2 = *n2++))
> continue;
> @@ -442,10 +440,8 @@ static int ntfs_d_compare(const struct dentry *dentry, unsigned int len1,
> if (c1 >= 0x80 || c2 >= 0x80)
> break;
>
> - if (toupper(c1) != toupper(c2)) {
> - ret = 1;
> - goto out;
> - }
> + if (toupper(c1) != toupper(c2))
> + return 1;
> }
>
> /*
>
> base-commit: d45da67caedacd500879de5e649360cc70777af7
> --
> 2.37.3
>
>

2022-10-26 16:58:53

by Konstantin Komarov

Subject: Re: [PATCH -next v2 1/2] fs/ntfs3: Don't use uni1 uninitialized in ntfs_d_compare()

On 10/21/22 20:10, Nathan Chancellor wrote:
> Ping? This is still breaking our builds in -next...
>

Thanks for patch, applied!

> On Tue, Oct 04, 2022 at 04:23:58PM -0700, Nathan Chancellor wrote:
>> Clang warns:
>>
>> fs/ntfs3/namei.c:445:7: error: variable 'uni1' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
>> if (toupper(c1) != toupper(c2)) {
>> ^~~~~~~~~~~~~~~~~~~~~~~~~~
>> ./include/linux/ctype.h:64:20: note: expanded from macro 'toupper'
>> #define toupper(c) __toupper(c)
>> ^
>> fs/ntfs3/namei.c:487:12: note: uninitialized use occurs here
>> __putname(uni1);
>> ^~~~
>> ./include/linux/fs.h:2789:65: note: expanded from macro '__putname'
>> #define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
>> ^~~~
>> fs/ntfs3/namei.c:445:3: note: remove the 'if' if its condition is always false
>> if (toupper(c1) != toupper(c2)) {
>> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> fs/ntfs3/namei.c:434:7: error: variable 'uni1' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
>> if (!lm--) {
>> ^~~~~
>> fs/ntfs3/namei.c:487:12: note: uninitialized use occurs here
>> __putname(uni1);
>> ^~~~
>> ./include/linux/fs.h:2789:65: note: expanded from macro '__putname'
>> #define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
>> ^~~~
>> fs/ntfs3/namei.c:434:3: note: remove the 'if' if its condition is always false
>> if (!lm--) {
>> ^~~~~~~~~~~~
>> fs/ntfs3/namei.c:430:22: note: initialize the variable 'uni1' to silence this warning
>> struct cpu_str *uni1, *uni2;
>> ^
>> = NULL
>> 2 errors generated.
>>
>> There is no point in calling __putname() in these particular error
>> paths, as there has been no corresponding __getname() call yet. Just
>> return directly in these blocks to clear up the warning.
>>
>> Fixes: a3a956c78efa ("fs/ntfs3: Add option "nocase"")
>> Link: https://github.com/ClangBuiltLinux/linux/issues/1729
>> Reviewed-by: Nick Desaulniers <[email protected]>
>> Signed-off-by: Nathan Chancellor <[email protected]>
>> ---
>>
>> v2:
>> * Pick up Nick's reviewed-by tag.
>> v1: https://lore.kernel.org/[email protected]/
>>
>> fs/ntfs3/namei.c | 12 ++++--------
>> 1 file changed, 4 insertions(+), 8 deletions(-)
>>
>> diff --git a/fs/ntfs3/namei.c b/fs/ntfs3/namei.c
>> index 315763eb05ff..5d3a6ce3f05f 100644
>> --- a/fs/ntfs3/namei.c
>> +++ b/fs/ntfs3/namei.c
>> @@ -431,10 +431,8 @@ static int ntfs_d_compare(const struct dentry *dentry, unsigned int len1,
>>
>> /* First try fast implementation. */
>> for (;;) {
>> - if (!lm--) {
>> - ret = len1 == len2 ? 0 : 1;
>> - goto out;
>> - }
>> + if (!lm--)
>> + return len1 == len2 ? 0 : 1;
>>
>> if ((c1 = *n1++) == (c2 = *n2++))
>> continue;
>> @@ -442,10 +440,8 @@ static int ntfs_d_compare(const struct dentry *dentry, unsigned int len1,
>> if (c1 >= 0x80 || c2 >= 0x80)
>> break;
>>
>> - if (toupper(c1) != toupper(c2)) {
>> - ret = 1;
>> - goto out;
>> - }
>> + if (toupper(c1) != toupper(c2))
>> + return 1;
>> }
>>
>> /*
>>
>> base-commit: d45da67caedacd500879de5e649360cc70777af7
>> --
>> 2.37.3
>>
>>

2022-11-12 18:36:55

by Konstantin Komarov

Subject: Re: [PATCH -next v2 2/2] fs/ntfs3: Eliminate unnecessary ternary operator in ntfs_d_compare()

On 10/5/22 02:23, Nathan Chancellor wrote:
> 'a == b ? 0 : 1' is logically equivalent to 'a != b'.
>
> Suggested-by: Nick Desaulniers <[email protected]>
> Signed-off-by: Nathan Chancellor <[email protected]>
> ---
>
> v2: New patch.
>
> fs/ntfs3/namei.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/ntfs3/namei.c b/fs/ntfs3/namei.c
> index 5d3a6ce3f05f..6b0d2c01d6ff 100644
> --- a/fs/ntfs3/namei.c
> +++ b/fs/ntfs3/namei.c
> @@ -432,7 +432,7 @@ static int ntfs_d_compare(const struct dentry *dentry, unsigned int len1,
> /* First try fast implementation. */
> for (;;) {
> if (!lm--)
> - return len1 == len2 ? 0 : 1;
> + return len1 != len2;
>
> if ((c1 = *n1++) == (c2 = *n2++))
> continue;

Thank you for your work, applied!
First patch was already applied.