[PATCH v3 02/28] regularize emptiness checks in fini_module(2) and vfs_dedupe_file_range()
From: Al Viro <viro@zeniv.linux.org.uk>
Date: 2024-11-02 05:08:38
Also in:
cgroups, kvm, linux-fsdevel
Subsystem:
filesystems (vfs and infrastructure), module support, the rest · Maintainers:
Alexander Viro, Christian Brauner, Luis Chamberlain, Petr Pavlu, Daniel Gomez, Sami Tolvanen, Linus Torvalds
With few exceptions emptiness checks are done as fd_file(...) in boolean context (usually something like if (!fd_file(f))...); those will be taken care of later. However, there's a couple of places where we do those checks as 'store fd_file(...) into a variable, then check if this variable is NULL' and those are harder to spot. Get rid of those now. use fd_empty() instead of extracting file and then checking it for NULL. Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> --- fs/remap_range.c | 5 ++--- kernel/module/main.c | 4 +++- 2 files changed, 5 insertions(+), 4 deletions(-)
diff --git a/fs/remap_range.c b/fs/remap_range.c
index 4403d5c68fcb..017d0d1ea6c9 100644
--- a/fs/remap_range.c
+++ b/fs/remap_range.c@@ -537,9 +537,8 @@ int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same) for (i = 0, info = same->info; i < count; i++, info++) { struct fd dst_fd = fdget(info->dest_fd); - struct file *dst_file = fd_file(dst_fd); - if (!dst_file) { + if (fd_empty(dst_fd)) { info->status = -EBADF; goto next_loop; }
@@ -549,7 +548,7 @@ int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same) goto next_fdput; } - deduped = vfs_dedupe_file_range_one(file, off, dst_file, + deduped = vfs_dedupe_file_range_one(file, off, fd_file(dst_fd), info->dest_offset, len, REMAP_FILE_CAN_SHORTEN); if (deduped == -EBADE)
diff --git a/kernel/module/main.c b/kernel/module/main.c
index 49b9bca9de12..d785973d8a51 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c@@ -3202,7 +3202,7 @@ static int idempotent_init_module(struct file *f, const char __user * uargs, int { struct idempotent idem; - if (!f || !(f->f_mode & FMODE_READ)) + if (!(f->f_mode & FMODE_READ)) return -EBADF; /* Are we the winners of the race and get to do this? */
@@ -3234,6 +3234,8 @@ SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags) return -EINVAL; f = fdget(fd); + if (fd_empty(f)) + return -EBADF; err = idempotent_init_module(fd_file(f), uargs, flags); fdput(f); return err;
--
2.39.5