From 96840aa00a031069a136ec4c55d0bdd09ac6d3a7 Mon Sep 17 00:00:00 2001 From: Davi Arnaut Date: Fri, 24 Mar 2006 03:18:42 -0800 Subject: [PATCH] strndup_user() This patch series creates a strndup_user() function to easy copying C strings from userspace. Also we avoid common pitfalls like userspace modifying the final \0 after the strlen_user(). Signed-off-by: Davi Arnaut Cc: David Howells Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/util.c | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) (limited to 'mm/util.c') diff --git a/mm/util.c b/mm/util.c index 5f4bb59da63c..49e29f751b50 100644 --- a/mm/util.c +++ b/mm/util.c @@ -1,6 +1,8 @@ #include #include #include +#include +#include /** * kzalloc - allocate memory. The memory is set to zero. @@ -37,3 +39,38 @@ char *kstrdup(const char *s, gfp_t gfp) return buf; } EXPORT_SYMBOL(kstrdup); + +/* + * strndup_user - duplicate an existing string from user space + * + * @s: The string to duplicate + * @n: Maximum number of bytes to copy, including the trailing NUL. + */ +char *strndup_user(const char __user *s, long n) +{ + char *p; + long length; + + length = strnlen_user(s, n); + + if (!length) + return ERR_PTR(-EFAULT); + + if (length > n) + return ERR_PTR(-EINVAL); + + p = kmalloc(length, GFP_KERNEL); + + if (!p) + return ERR_PTR(-ENOMEM); + + if (copy_from_user(p, s, length)) { + kfree(p); + return ERR_PTR(-EFAULT); + } + + p[length - 1] = '\0'; + + return p; +} +EXPORT_SYMBOL(strndup_user); -- cgit v1.2.2 From 871751e25d956ad24f129ca972b7851feaa61d53 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 25 Mar 2006 03:06:39 -0800 Subject: [PATCH] slab: implement /proc/slab_allocators Implement /proc/slab_allocators. It produces output like: idr_layer_cache: 80 idr_pre_get+0x33/0x4e buffer_head: 2555 alloc_buffer_head+0x20/0x75 mm_struct: 9 mm_alloc+0x1e/0x42 mm_struct: 20 dup_mm+0x36/0x370 vm_area_struct: 384 dup_mm+0x18f/0x370 vm_area_struct: 151 do_mmap_pgoff+0x2e0/0x7c3 vm_area_struct: 1 split_vma+0x5a/0x10e vm_area_struct: 11 do_brk+0x206/0x2e2 vm_area_struct: 2 copy_vma+0xda/0x142 vm_area_struct: 9 setup_arg_pages+0x99/0x214 fs_cache: 8 copy_fs_struct+0x21/0x133 fs_cache: 29 copy_process+0xf38/0x10e3 files_cache: 30 alloc_files+0x1b/0xcf signal_cache: 81 copy_process+0xbaa/0x10e3 sighand_cache: 77 copy_process+0xe65/0x10e3 sighand_cache: 1 de_thread+0x4d/0x5f8 anon_vma: 241 anon_vma_prepare+0xd9/0xf3 size-2048: 1 add_sect_attrs+0x5f/0x145 size-2048: 2 journal_init_revoke+0x99/0x302 size-2048: 2 journal_init_revoke+0x137/0x302 size-2048: 2 journal_init_inode+0xf9/0x1c4 Cc: Manfred Spraul Cc: Alexander Nyberg Cc: Pekka Enberg Cc: Christoph Lameter Cc: Ravikiran Thirumalai Signed-off-by: Al Viro DESC slab-leaks3-locking-fix EDESC From: Andrew Morton Update for slab-remove-cachep-spinlock.patch Cc: Al Viro Cc: Manfred Spraul Cc: Alexander Nyberg Cc: Pekka Enberg Cc: Christoph Lameter Cc: Ravikiran Thirumalai Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/util.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'mm/util.c') diff --git a/mm/util.c b/mm/util.c index 49e29f751b50..b68d3d7d0359 100644 --- a/mm/util.c +++ b/mm/util.c @@ -11,7 +11,7 @@ */ void *kzalloc(size_t size, gfp_t flags) { - void *ret = kmalloc(size, flags); + void *ret = ____kmalloc(size, flags); if (ret) memset(ret, 0, size); return ret; @@ -33,7 +33,7 @@ char *kstrdup(const char *s, gfp_t gfp) return NULL; len = strlen(s) + 1; - buf = kmalloc(len, gfp); + buf = ____kmalloc(len, gfp); if (buf) memcpy(buf, s, len); return buf; -- cgit v1.2.2 From 40c07ae8daa659b8feb149c84731629386873c16 Mon Sep 17 00:00:00 2001 From: Pekka Enberg Date: Sat, 25 Mar 2006 03:06:43 -0800 Subject: [PATCH] slab: optimize constant-size kzalloc calls As suggested by Eric Dumazet, optimize kzalloc() calls that pass a compile-time constant size. Please note that the patch increases kernel text slightly (~200 bytes for defconfig on x86). Signed-off-by: Pekka Enberg Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/util.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'mm/util.c') diff --git a/mm/util.c b/mm/util.c index b68d3d7d0359..7368479220b3 100644 --- a/mm/util.c +++ b/mm/util.c @@ -5,18 +5,18 @@ #include /** - * kzalloc - allocate memory. The memory is set to zero. + * __kzalloc - allocate memory. The memory is set to zero. * @size: how many bytes of memory are required. * @flags: the type of memory to allocate. */ -void *kzalloc(size_t size, gfp_t flags) +void *__kzalloc(size_t size, gfp_t flags) { void *ret = ____kmalloc(size, flags); if (ret) memset(ret, 0, size); return ret; } -EXPORT_SYMBOL(kzalloc); +EXPORT_SYMBOL(__kzalloc); /* * kstrdup - allocate space for and copy an existing string -- cgit v1.2.2