14 Commits

Author SHA1 Message Date
Josh Law
c9ba82624b lib/glob: initialize back_str to silence uninitialized variable warning
back_str is only used when back_pat is non-NULL, and both are always set
together, so it is safe in practice.  Initialize back_str to NULL to make
this safety invariant explicit and silence compiler/static analysis
warnings.

Link: https://lkml.kernel.org/r/20260312215249.50165-1-objecting@objecting.org
Signed-off-by: Josh Law <objecting@objecting.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-03-27 21:19:45 -07:00
Josh Law
90c73d0bfa lib/glob: clean up "bool abuse" in pointer arithmetic
Replace the implicit 'bool' to 'int' conversion with an explicit ternary
operator.  This makes the pointer arithmetic clearer and avoids relying on
boolean memory representation for logic flow.

Link: https://lkml.kernel.org/r/20260301203845.2617217-1-objecting@objecting.org
Signed-off-by: Josh Law <objecting@objecting.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-03-27 21:19:38 -07:00
Josh Law
33a3dd9bfd lib: glob: replace bitwise OR with logical operation on boolean
Using bitwise OR (|=) on a boolean variable is valid C, but replacing it
with a direct logical assignment makes the intent clearer and appeases
strict static analysis tools.

Link: https://lkml.kernel.org/r/20260301152143.2572137-2-objecting@objecting.org
Signed-off-by: Josh Law <objecting@objecting.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-03-27 21:19:37 -07:00
Josh Law
f5e74cbdbe lib: glob: add explicit include for export.h
Include <linux/export.h> explicitly instead of relying on it being
implicitly included by <linux/module.h> for the EXPORT_SYMBOL macro.

Link: https://lkml.kernel.org/r/20260301152143.2572137-1-objecting@objecting.org
Signed-off-by: Josh Law <objecting@objecting.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-03-27 21:19:37 -07:00
Josh Law
3a1c3be178 lib: glob: fix grammar and replace non-inclusive terminology
Fix a missing article ('a') in the comment describing the glob
implementation, and replace 'blacklists' with 'denylists' to align with
the kernel's inclusive terminology guidelines.

Link: https://lkml.kernel.org/r/20260301154553.2592681-1-objecting@objecting.org
Signed-off-by: Josh Law <objecting@objecting.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-03-27 21:19:37 -07:00
Josh Law
ac2428c141 lib: glob: add missing SPDX-License-Identifier
Add the missing dual MIT/GPL license identifier to glob.c.

Link: https://lkml.kernel.org/r/20260228195300.2468310-1-objecting@objecting.org
Signed-off-by: Josh Law <objecting@objecting.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-03-27 21:19:36 -07:00
Alok Swaminathan
7b0a5b6669 lib: glob.c: added null check for character class
Add null check for character class.  Previously, an inverted character
class could result in a nul byte being matched and lead to the function
reading past the end of the inputted string.

Link: https://lkml.kernel.org/r/20240826155709.12383-1-swaminathanalok@gmail.com
Signed-off-by: Alok Swaminathan <swaminathanalok@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-09 16:47:41 -07:00
Tom Rix
d1bd5fa076 lib: remove back_str initialization
Clang static analysis reports this false positive
glob.c:48:32: warning: Assigned value is garbage
  or undefined
  char const *back_pat = NULL, *back_str = back_str;
                                ^~~~~~~~   ~~~~~~~~

back_str is set after back_pat and it's use is protected by the !back_pat
check.  It is not necessary to initialize back_str, so remove the
initialization.

Link: https://lkml.kernel.org/r/20220402131546.3383578-1-trix@redhat.com
Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-04-29 14:38:01 -07:00
Nick Desaulniers
4c1ca831ad Revert "lib: Revert use of fallthrough pseudo-keyword in lib/"
This reverts commit 6a9dc5fd61 ("lib: Revert use of fallthrough
pseudo-keyword in lib/")

Now that we can build arch/powerpc/boot/ free of -Wimplicit-fallthrough,
re-enable these fixes for lib/.

Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://github.com/ClangBuiltLinux/linux/issues/236
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-11-18 14:15:17 -06:00
Gustavo A. R. Silva
6a9dc5fd61 lib: Revert use of fallthrough pseudo-keyword in lib/
The following build error for powerpc64 was reported by Nathan Chancellor:

  "$ scripts/config --file arch/powerpc/configs/powernv_defconfig -e KERNEL_XZ

   $ make -skj"$(nproc)" ARCH=powerpc CROSS_COMPILE=powerpc64le-linux- distclean powernv_defconfig zImage
   ...
   In file included from arch/powerpc/boot/../../../lib/decompress_unxz.c:234,
                    from arch/powerpc/boot/decompress.c:38:
   arch/powerpc/boot/../../../lib/xz/xz_dec_stream.c: In function 'dec_main':
   arch/powerpc/boot/../../../lib/xz/xz_dec_stream.c:586:4: error: 'fallthrough' undeclared (first use in this function)
     586 |    fallthrough;
         |    ^~~~~~~~~~~

   This will end up affecting distribution configurations such as Debian
   and OpenSUSE according to my testing. I am not sure what the solution
   is, the PowerPC wrapper does not set -D__KERNEL__ so I am not sure
   that compiler_attributes.h can be safely included."

In order to avoid these sort of problems, it seems that the best
solution is to use /* fall through */ comments instead of the
fallthrough pseudo-keyword macro in lib/, for now.

Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Fixes: df561f6688 ("treewide: Use fallthrough pseudo-keyword")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-and-tested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-24 14:17:44 -07:00
Gustavo A. R. Silva
df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Geert Uytterhoeven
ba95b045e9 lib: add module support to glob tests
Extract the glob test code into its own source file, to allow to compile
it either to a loadable module, or builtin into the kernel.

Link: http://lkml.kernel.org/r/1483470276-10517-2-git-send-email-geert@linux-m68k.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:57 -08:00
George Spelvin
5f9be8248d lib/glob.c: add CONFIG_GLOB_SELFTEST
This was useful during development, and is retained for future
regression testing.

GCC appears to have no way to place string literals in a particular
section; adding __initconst to a char pointer leaves the string itself
in the default string section, where it will not be thrown away after
module load.

Thus all string constants are kept in explicitly declared and named
arrays.  Sorry this makes printk a bit harder to read.  At least the
tests are more compact.

Signed-off-by: George Spelvin <linux@horizon.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-06 18:01:25 -07:00
George Spelvin
b01250856b lib: add lib/glob.c
This is a helper function from drivers/ata/libata_core.c, where it is
used to blacklist particular device models.  It's being moved to lib/ so
other drivers may use it for the same purpose.

This implementation in non-recursive, so is safe for the kernel stack.

[akpm@linux-foundation.org: fix sparse warning]
Signed-off-by: George Spelvin <linux@horizon.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-06 18:01:24 -07:00