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| author | Al Viro <viro@zeniv.linux.org.uk> | 2022-09-26 17:59:14 +0200 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2022-09-28 20:28:40 +0200 |
| commit | 06bbaa6dc53cb72040db952053432541acb9adc7 (patch) | |
| tree | 113842569565963748044a4b00498e31051a68c1 /fs/internal.h | |
| parent | nfsd_splice_actor(): handle compound pages (diff) | |
| download | linux-06bbaa6dc53cb72040db952053432541acb9adc7.tar.xz linux-06bbaa6dc53cb72040db952053432541acb9adc7.zip | |
[coredump] don't use __kernel_write() on kmap_local_page()
passing kmap_local_page() result to __kernel_write() is unsafe -
random ->write_iter() might (and 9p one does) get unhappy when
passed ITER_KVEC with pointer that came from kmap_local_page().
Fix by providing a variant of __kernel_write() that takes an iov_iter
from caller (__kernel_write() becomes a trivial wrapper) and adding
dump_emit_page() that parallels dump_emit(), except that instead of
__kernel_write() it uses __kernel_write_iter() with ITER_BVEC source.
Fixes: 3159ed57792b "fs/coredump: use kmap_local_page()"
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs/internal.h')
| -rw-r--r-- | fs/internal.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/fs/internal.h b/fs/internal.h index 87e96b9024ce..3e206d3e317c 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -16,6 +16,7 @@ struct shrink_control; struct fs_context; struct user_namespace; struct pipe_inode_info; +struct iov_iter; /* * block/bdev.c @@ -221,3 +222,5 @@ ssize_t do_getxattr(struct user_namespace *mnt_userns, int setxattr_copy(const char __user *name, struct xattr_ctx *ctx); int do_setxattr(struct user_namespace *mnt_userns, struct dentry *dentry, struct xattr_ctx *ctx); + +ssize_t __kernel_write_iter(struct file *file, struct iov_iter *from, loff_t *pos); |