commit cadf1ccf1b0021d0b7a9347e102ac5258f9f98c8 upstream.
This patch enhances the missing error handling code for
xattr submodule, which improves the stability for the rare cases.
Reviewed-by: Chao Yu <yuchao0@xxxxxxxxxx>
Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
Signed-off-by: Gao Xiang <gaoxiang25@xxxxxxxxxx>
---
This series resolves the following conflicts:
FAILED: patch "[PATCH] staging: erofs: fix fast symlink w/o xattr when fs xattr is" failed to apply to 4.19-stable tree
FAILED: patch "[PATCH] staging: erofs: fix memleak of inode's shared xattr array" failed to apply to 4.19-stable tree
FAILED: patch "[PATCH] staging: erofs: fix race of initializing xattrs of a inode at" failed to apply to 4.19-stable tree
FAILED: patch "[PATCH] staging: erofs: keep corrupted fs from crashing kernel in" failed to apply to 4.19-stable tree
In addition, there is another patch called
staging: erofs: add error handling for xattr submodule
that needs to be backported to 4.19 as well (4.20+ already has this patch.)
drivers/staging/erofs/internal.h | 5 +-
drivers/staging/erofs/xattr.c | 112 +++++++++++++++++++++++++++------------
2 files changed, 81 insertions(+), 36 deletions(-)
diff --git a/drivers/staging/erofs/internal.h b/drivers/staging/erofs/internal.h
index 9f44ed8f0023..1c048c412fb2 100644
--- a/drivers/staging/erofs/internal.h
+++ b/drivers/staging/erofs/internal.h
@@ -485,8 +485,9 @@ struct erofs_map_blocks_iter {
};
-static inline struct page *erofs_get_inline_page(struct inode *inode,
- erofs_blk_t blkaddr)
+static inline struct page *
+erofs_get_inline_page(struct inode *inode,
+ erofs_blk_t blkaddr)
{
return erofs_get_meta_page(inode->i_sb,
blkaddr, S_ISDIR(inode->i_mode));
diff --git a/drivers/staging/erofs/xattr.c b/drivers/staging/erofs/xattr.c
index 0e9cfeccdf99..d4bccb57e7c3 100644
--- a/drivers/staging/erofs/xattr.c
+++ b/drivers/staging/erofs/xattr.c
@@ -24,16 +24,25 @@ struct xattr_iter {
static inline void xattr_iter_end(struct xattr_iter *it, bool atomic)
{
- /* only init_inode_xattrs use non-atomic once */
+ /* the only user of kunmap() is 'init_inode_xattrs' */
if (unlikely(!atomic))
kunmap(it->page);
else
kunmap_atomic(it->kaddr);
+
unlock_page(it->page);
put_page(it->page);
}
-static void init_inode_xattrs(struct inode *inode)
+static inline void xattr_iter_end_final(struct xattr_iter *it)
+{
+ if (!it->page)
+ return;
+
+ xattr_iter_end(it, true);
+}
+
+static int init_inode_xattrs(struct inode *inode)
{
struct xattr_iter it;
unsigned i;
@@ -43,7 +52,7 @@ static void init_inode_xattrs(struct inode *inode)
bool atomic_map;
if (likely(inode_has_inited_xattr(inode)))
- return;
+ return 0;
vi = EROFS_V(inode);
BUG_ON(!vi->xattr_isize);
@@ -53,7 +62,8 @@ static void init_inode_xattrs(struct inode *inode)
it.ofs = erofs_blkoff(iloc(sbi, vi->nid) + vi->inode_isize);
it.page = erofs_get_inline_page(inode, it.blkaddr);
- BUG_ON(IS_ERR(it.page));
+ if (IS_ERR(it.page))
+ return PTR_ERR(it.page);
/* read in shared xattr array (non-atomic, see kmalloc below) */
it.kaddr = kmap(it.page);
@@ -62,9 +72,12 @@ static void init_inode_xattrs(struct inode *inode)
ih = (struct erofs_xattr_ibody_header *)(it.kaddr + it.ofs);
vi->xattr_shared_count = ih->h_shared_count;
- vi->xattr_shared_xattrs = (unsigned *)kmalloc_array(
- vi->xattr_shared_count, sizeof(unsigned),
- GFP_KERNEL | __GFP_NOFAIL);
+ vi->xattr_shared_xattrs = kmalloc_array(vi->xattr_shared_count,
+ sizeof(uint), GFP_KERNEL);
+ if (!vi->xattr_shared_xattrs) {
+ xattr_iter_end(&it, atomic_map);
+ return -ENOMEM;
+ }
/* let's skip ibody header */
it.ofs += sizeof(struct erofs_xattr_ibody_header);
@@ -77,7 +90,8 @@ static void init_inode_xattrs(struct inode *inode)
it.page = erofs_get_meta_page(inode->i_sb,
++it.blkaddr, S_ISDIR(inode->i_mode));
- BUG_ON(IS_ERR(it.page));
+ if (IS_ERR(it.page))
+ return PTR_ERR(it.page);
it.kaddr = kmap_atomic(it.page);
atomic_map = true;
@@ -90,6 +104,7 @@ static void init_inode_xattrs(struct inode *inode)
xattr_iter_end(&it, atomic_map);
inode_set_inited_xattr(inode);
+ return 0;
}
struct xattr_iter_handlers {
@@ -99,18 +114,25 @@ struct xattr_iter_handlers {
void (*value)(struct xattr_iter *, unsigned, char *, unsigned);
};
-static void xattr_iter_fixup(struct xattr_iter *it)
+static inline int xattr_iter_fixup(struct xattr_iter *it)
{
- if (unlikely(it->ofs >= EROFS_BLKSIZ)) {
- xattr_iter_end(it, true);
+ if (it->ofs < EROFS_BLKSIZ)
+ return 0;
- it->blkaddr += erofs_blknr(it->ofs);
- it->page = erofs_get_meta_page(it->sb, it->blkaddr, false);
- BUG_ON(IS_ERR(it->page));
+ xattr_iter_end(it, true);
- it->kaddr = kmap_atomic(it->page);
- it->ofs = erofs_blkoff(it->ofs);
+ it->blkaddr += erofs_blknr(it->ofs);
+ it->page = erofs_get_meta_page(it->sb, it->blkaddr, false);
+ if (IS_ERR(it->page)) {
+ int err = PTR_ERR(it->page);
+
+ it->page = NULL;
+ return err;
}
+
+ it->kaddr = kmap_atomic(it->page);
+ it->ofs = erofs_blkoff(it->ofs);
+ return 0;
}
static int inline_xattr_iter_begin(struct xattr_iter *it,
@@ -132,21 +154,24 @@ static int inline_xattr_iter_begin(struct xattr_iter *it,
it->ofs = erofs_blkoff(iloc(sbi, vi->nid) + inline_xattr_ofs);
it->page = erofs_get_inline_page(inode, it->blkaddr);
- BUG_ON(IS_ERR(it->page));
- it->kaddr = kmap_atomic(it->page);
+ if (IS_ERR(it->page))
+ return PTR_ERR(it->page);
+ it->kaddr = kmap_atomic(it->page);
return vi->xattr_isize - xattr_header_sz;
}
static int xattr_foreach(struct xattr_iter *it,
- struct xattr_iter_handlers *op, unsigned *tlimit)
+ const struct xattr_iter_handlers *op, unsigned int *tlimit)
{
struct erofs_xattr_entry entry;
unsigned value_sz, processed, slice;
int err;
/* 0. fixup blkaddr, ofs, ipage */
- xattr_iter_fixup(it);
+ err = xattr_iter_fixup(it);
+ if (err)
+ return err;
/*
* 1. read xattr entry to the memory,
@@ -178,7 +203,9 @@ static int xattr_foreach(struct xattr_iter *it,
if (it->ofs >= EROFS_BLKSIZ) {
BUG_ON(it->ofs > EROFS_BLKSIZ);
- xattr_iter_fixup(it);
+ err = xattr_iter_fixup(it);
+ if (err)
+ goto out;
it->ofs = 0;
}
@@ -210,7 +237,10 @@ static int xattr_foreach(struct xattr_iter *it,
while (processed < value_sz) {
if (it->ofs >= EROFS_BLKSIZ) {
BUG_ON(it->ofs > EROFS_BLKSIZ);
- xattr_iter_fixup(it);
+
+ err = xattr_iter_fixup(it);
+ if (err)
+ goto out;
it->ofs = 0;
}
@@ -270,7 +300,7 @@ static void xattr_copyvalue(struct xattr_iter *_it,
memcpy(it->buffer + processed, buf, len);
}
-static struct xattr_iter_handlers find_xattr_handlers = {
+static const struct xattr_iter_handlers find_xattr_handlers = {
.entry = xattr_entrymatch,
.name = xattr_namematch,
.alloc_buffer = xattr_checkbuffer,
@@ -291,8 +321,11 @@ static int inline_getxattr(struct inode *inode, struct getxattr_iter *it)
ret = xattr_foreach(&it->it, &find_xattr_handlers, &remaining);
if (ret >= 0)
break;
+
+ if (ret != -ENOATTR) /* -ENOMEM, -EIO, etc. */
+ break;
}
- xattr_iter_end(&it->it, true);
+ xattr_iter_end_final(&it->it);
return ret < 0 ? ret : it->buffer_size;
}
@@ -315,8 +348,10 @@ static int shared_getxattr(struct inode *inode, struct getxattr_iter *it)
xattr_iter_end(&it->it, true);
it->it.page = erofs_get_meta_page(inode->i_sb,
- blkaddr, false);
- BUG_ON(IS_ERR(it->it.page));
+ blkaddr, false);
+ if (IS_ERR(it->it.page))
+ return PTR_ERR(it->it.page);
+
it->it.kaddr = kmap_atomic(it->it.page);
it->it.blkaddr = blkaddr;
}
@@ -324,9 +359,12 @@ static int shared_getxattr(struct inode *inode, struct getxattr_iter *it)
ret = xattr_foreach(&it->it, &find_xattr_handlers, NULL);
if (ret >= 0)
break;
+
+ if (ret != -ENOATTR) /* -ENOMEM, -EIO, etc. */
+ break;
}
if (vi->xattr_shared_count)
- xattr_iter_end(&it->it, true);
+ xattr_iter_end_final(&it->it);
return ret < 0 ? ret : it->buffer_size;
}
@@ -351,7 +389,9 @@ int erofs_getxattr(struct inode *inode, int index,
if (unlikely(name == NULL))
return -EINVAL;
- init_inode_xattrs(inode);
+ ret = init_inode_xattrs(inode);
+ if (ret)
+ return ret;
it.index = index;
@@ -494,7 +534,7 @@ static int xattr_skipvalue(struct xattr_iter *_it,
return 1;
}
-static struct xattr_iter_handlers list_xattr_handlers = {
+static const struct xattr_iter_handlers list_xattr_handlers = {
.entry = xattr_entrylist,
.name = xattr_namelist,
.alloc_buffer = xattr_skipvalue,
@@ -516,7 +556,7 @@ static int inline_listxattr(struct listxattr_iter *it)
if (ret < 0)
break;
}
- xattr_iter_end(&it->it, true);
+ xattr_iter_end_final(&it->it);
return ret < 0 ? ret : it->buffer_ofs;
}
@@ -538,8 +578,10 @@ static int shared_listxattr(struct listxattr_iter *it)
xattr_iter_end(&it->it, true);
it->it.page = erofs_get_meta_page(inode->i_sb,
- blkaddr, false);
- BUG_ON(IS_ERR(it->it.page));
+ blkaddr, false);
+ if (IS_ERR(it->it.page))
+ return PTR_ERR(it->it.page);
+
it->it.kaddr = kmap_atomic(it->it.page);
it->it.blkaddr = blkaddr;
}
@@ -549,7 +591,7 @@ static int shared_listxattr(struct listxattr_iter *it)
break;
}
if (vi->xattr_shared_count)
- xattr_iter_end(&it->it, true);
+ xattr_iter_end_final(&it->it);
return ret < 0 ? ret : it->buffer_ofs;
}
@@ -560,7 +602,9 @@ ssize_t erofs_listxattr(struct dentry *dentry,
int ret;
struct listxattr_iter it;
- init_inode_xattrs(d_inode(dentry));
+ ret = init_inode_xattrs(d_inode(dentry));
+ if (ret)
+ return ret;
it.dentry = dentry;
it.buffer = buffer;
--
2.14.5
