| Message ID | 20250325125905.395372-1-marc.dionne@auristor.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | cachefiles: Fix oops in vfs_mkdir from cachefiles_get_directory | expand |
On Tue, 25 Mar 2025 09:59:05 -0300, Marc Dionne wrote: > Commit c54b386969a5 ("VFS: Change vfs_mkdir() to return the dentry.") > changed cachefiles_get_directory, replacing "subdir" with a ERR_PTR > from the result of cachefiles_inject_write_error, which is either 0 > or some error code. This causes an oops when the resulting pointer > is passed to vfs_mkdir. > > Use a similar pattern to what is used earlier in the function; replace > subdir with either the return value from vfs_mkdir, or the ERR_PTR > of the cachefiles_inject_write_error() return value, but only if it > is non zero. > > [...] Applied to the vfs.fixes branch of the vfs/vfs.git tree. Patches in the vfs.fixes branch should appear in linux-next soon. Please report any outstanding bugs that were missed during review in a new review to the original patch series allowing us to drop it. It's encouraged to provide Acked-bys and Reviewed-bys even though the patch has now been applied. If possible patch trailers will be updated. Note that commit hashes shown below are subject to change due to rebase, trailer updates or similar. If in doubt, please check the listed branch. tree: https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git branch: vfs.fixes [1/1] cachefiles: Fix oops in vfs_mkdir from cachefiles_get_directory https://git.kernel.org/vfs/vfs/c/406fad7698f5
On Tue, 25 Mar 2025, Marc Dionne wrote: > Commit c54b386969a5 ("VFS: Change vfs_mkdir() to return the dentry.") > changed cachefiles_get_directory, replacing "subdir" with a ERR_PTR > from the result of cachefiles_inject_write_error, which is either 0 > or some error code. This causes an oops when the resulting pointer > is passed to vfs_mkdir. Thanks for fixing that - now that I look at my code again it is obviously wrong :-( Reviewed-by: NeilBrown <neilb@sue.de> Thanks, NeilBrown > > Use a similar pattern to what is used earlier in the function; replace > subdir with either the return value from vfs_mkdir, or the ERR_PTR > of the cachefiles_inject_write_error() return value, but only if it > is non zero. > > Fixes: c54b386969a5 ("VFS: Change vfs_mkdir() to return the dentry.") > cc: netfs@lists.linux.dev > Signed-off-by: Marc Dionne <marc.dionne@auristor.com> > --- > fs/cachefiles/namei.c | 7 ++++--- > 1 file changed, 4 insertions(+), 3 deletions(-) > > diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c > index 83a60126de0f..14d0cc894000 100644 > --- a/fs/cachefiles/namei.c > +++ b/fs/cachefiles/namei.c > @@ -128,10 +128,11 @@ struct dentry *cachefiles_get_directory(struct cachefiles_cache *cache, > ret = security_path_mkdir(&path, subdir, 0700); > if (ret < 0) > goto mkdir_error; > - subdir = ERR_PTR(cachefiles_inject_write_error()); > - if (!IS_ERR(subdir)) > + ret = cachefiles_inject_write_error(); > + if (ret == 0) > subdir = vfs_mkdir(&nop_mnt_idmap, d_inode(dir), subdir, 0700); > - ret = PTR_ERR(subdir); > + else > + subdir = ERR_PTR(ret); > if (IS_ERR(subdir)) { > trace_cachefiles_vfs_error(NULL, d_inode(dir), ret, > cachefiles_trace_mkdir_error); > -- > 2.48.1 > >
diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c index 83a60126de0f..14d0cc894000 100644 --- a/fs/cachefiles/namei.c +++ b/fs/cachefiles/namei.c @@ -128,10 +128,11 @@ struct dentry *cachefiles_get_directory(struct cachefiles_cache *cache, ret = security_path_mkdir(&path, subdir, 0700); if (ret < 0) goto mkdir_error; - subdir = ERR_PTR(cachefiles_inject_write_error()); - if (!IS_ERR(subdir)) + ret = cachefiles_inject_write_error(); + if (ret == 0) subdir = vfs_mkdir(&nop_mnt_idmap, d_inode(dir), subdir, 0700); - ret = PTR_ERR(subdir); + else + subdir = ERR_PTR(ret); if (IS_ERR(subdir)) { trace_cachefiles_vfs_error(NULL, d_inode(dir), ret, cachefiles_trace_mkdir_error);
Commit c54b386969a5 ("VFS: Change vfs_mkdir() to return the dentry.") changed cachefiles_get_directory, replacing "subdir" with a ERR_PTR from the result of cachefiles_inject_write_error, which is either 0 or some error code. This causes an oops when the resulting pointer is passed to vfs_mkdir. Use a similar pattern to what is used earlier in the function; replace subdir with either the return value from vfs_mkdir, or the ERR_PTR of the cachefiles_inject_write_error() return value, but only if it is non zero. Fixes: c54b386969a5 ("VFS: Change vfs_mkdir() to return the dentry.") cc: netfs@lists.linux.dev Signed-off-by: Marc Dionne <marc.dionne@auristor.com> --- fs/cachefiles/namei.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)