fs/ntfs3: Validate data run offset

This adds sanity checks for data run offset. We should make sure data
run offset is legit before trying to unpack them, otherwise we may
encounter use-after-free or some unexpected memory access behaviors.

[   82.940342] BUG: KASAN: use-after-free in run_unpack+0x2e3/0x570
[   82.941180] Read of size 1 at addr ffff888008a8487f by task mount/240
[   82.941670]
[   82.942069] CPU: 0 PID: 240 Comm: mount Not tainted 5.19.0+ #15
[   82.942482] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
[   82.943720] Call Trace:
[   82.944204]  <TASK>
[   82.944471]  dump_stack_lvl+0x49/0x63
[   82.944908]  print_report.cold+0xf5/0x67b
[   82.945141]  ? __wait_on_bit+0x106/0x120
[   82.945750]  ? run_unpack+0x2e3/0x570
[   82.946626]  kasan_report+0xa7/0x120
[   82.947046]  ? run_unpack+0x2e3/0x570
[   82.947280]  __asan_load1+0x51/0x60
[   82.947483]  run_unpack+0x2e3/0x570
[   82.947709]  ? memcpy+0x4e/0x70
[   82.947927]  ? run_pack+0x7a0/0x7a0
[   82.948158]  run_unpack_ex+0xad/0x3f0
[   82.948399]  ? mi_enum_attr+0x14a/0x200
[   82.948717]  ? run_unpack+0x570/0x570
[   82.949072]  ? ni_enum_attr_ex+0x1b2/0x1c0
[   82.949332]  ? ni_fname_type.part.0+0xd0/0xd0
[   82.949611]  ? mi_read+0x262/0x2c0
[   82.949970]  ? ntfs_cmp_names_cpu+0x125/0x180
[   82.950249]  ntfs_iget5+0x632/0x1870
[   82.950621]  ? ntfs_get_block_bmap+0x70/0x70
[   82.951192]  ? evict+0x223/0x280
[   82.951525]  ? iput.part.0+0x286/0x320
[   82.951969]  ntfs_fill_super+0x1321/0x1e20
[   82.952436]  ? put_ntfs+0x1d0/0x1d0
[   82.952822]  ? vsprintf+0x20/0x20
[   82.953188]  ? mutex_unlock+0x81/0xd0
[   82.953379]  ? set_blocksize+0x95/0x150
[   82.954001]  get_tree_bdev+0x232/0x370
[   82.954438]  ? put_ntfs+0x1d0/0x1d0
[   82.954700]  ntfs_fs_get_tree+0x15/0x20
[   82.955049]  vfs_get_tree+0x4c/0x130
[   82.955292]  path_mount+0x645/0xfd0
[   82.955615]  ? putname+0x80/0xa0
[   82.955955]  ? finish_automount+0x2e0/0x2e0
[   82.956310]  ? kmem_cache_free+0x110/0x390
[   82.956723]  ? putname+0x80/0xa0
[   82.957023]  do_mount+0xd6/0xf0
[   82.957411]  ? path_mount+0xfd0/0xfd0
[   82.957638]  ? __kasan_check_write+0x14/0x20
[   82.957948]  __x64_sys_mount+0xca/0x110
[   82.958310]  do_syscall_64+0x3b/0x90
[   82.958719]  entry_SYSCALL_64_after_hwframe+0x63/0xcd
[   82.959341] RIP: 0033:0x7fd0d1ce948a
[   82.960193] Code: 48 8b 0d 11 fa 2a 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 008
[   82.961532] RSP: 002b:00007ffe59ff69a8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
[   82.962527] RAX: ffffffffffffffda RBX: 0000564dcc107060 RCX: 00007fd0d1ce948a
[   82.963266] RDX: 0000564dcc107260 RSI: 0000564dcc1072e0 RDI: 0000564dcc10fce0
[   82.963686] RBP: 0000000000000000 R08: 0000564dcc107280 R09: 0000000000000020
[   82.964272] R10: 00000000c0ed0000 R11: 0000000000000202 R12: 0000564dcc10fce0
[   82.964785] R13: 0000564dcc107260 R14: 0000000000000000 R15: 00000000ffffffff

Signed-off-by: Edward Lo <edward.lo@ambergroup.io>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

5 files changed, 46 insertions, 0 deletions

diff --git a/fs/ntfs3/attrib.c b/fs/ntfs3/attrib.c
index 71f870d497ae..0d354560d323 100644
--- a/fs/ntfs3/attrib.c
+++ b/fs/ntfs3/attrib.c
@@ -101,6 +101,10 @@ static int attr_load_runs(struct ATTRIB *attr, struct ntfs_inode *ni,
 
 	asize = le32_to_cpu(attr->size);
 	run_off = le16_to_cpu(attr->nres.run_off);
+
+	if (run_off > asize)
+		return -EINVAL;
+
 	err = run_unpack_ex(run, ni->mi.sbi, ni->mi.rno, svcn, evcn,
 			    vcn ? *vcn : svcn, Add2Ptr(attr, run_off),
 			    asize - run_off);
@@ -1232,6 +1236,10 @@ int attr_load_runs_vcn(struct ntfs_inode *ni, enum ATTR_TYPE type,
 	}
 
 	ro = le16_to_cpu(attr->nres.run_off);
+
+	if (ro > le32_to_cpu(attr->size))
+		return -EINVAL;
+
 	err = run_unpack_ex(run, ni->mi.sbi, ni->mi.rno, svcn, evcn, svcn,
 			    Add2Ptr(attr, ro), le32_to_cpu(attr->size) - ro);
 	if (err < 0)
@@ -1901,6 +1909,11 @@ int attr_collapse_range(struct ntfs_inode *ni, u64 vbo, u64 bytes)
 			u16 le_sz;
 			u16 roff = le16_to_cpu(attr->nres.run_off);
 
+			if (roff > le32_to_cpu(attr->size)) {
+				err = -EINVAL;
+				goto out;
+			}
+
 			run_unpack_ex(RUN_DEALLOCATE, sbi, ni->mi.rno, svcn,
 				      evcn1 - 1, svcn, Add2Ptr(attr, roff),
 				      le32_to_cpu(attr->size) - roff);
diff --git a/fs/ntfs3/attrlist.c b/fs/ntfs3/attrlist.c
index bad6d8a849a2..c0c6bcbc8c05 100644
--- a/fs/ntfs3/attrlist.c
+++ b/fs/ntfs3/attrlist.c
@@ -68,6 +68,11 @@ int ntfs_load_attr_list(struct ntfs_inode *ni, struct ATTRIB *attr)
 
 		run_init(&ni->attr_list.run);
 
+		if (run_off > le32_to_cpu(attr->size)) {
+			err = -EINVAL;
+			goto out;
+		}
+
 		err = run_unpack_ex(&ni->attr_list.run, ni->mi.sbi, ni->mi.rno,
 				    0, le64_to_cpu(attr->nres.evcn), 0,
 				    Add2Ptr(attr, run_off),
diff --git a/fs/ntfs3/frecord.c b/fs/ntfs3/frecord.c
index 179b06762bdb..70a80f9412f7 100644
--- a/fs/ntfs3/frecord.c
+++ b/fs/ntfs3/frecord.c
@@ -568,6 +568,12 @@ static int ni_repack(struct ntfs_inode *ni)
 		}
 
 		roff = le16_to_cpu(attr->nres.run_off);
+
+		if (roff > le32_to_cpu(attr->size)) {
+			err = -EINVAL;
+			break;
+		}
+
 		err = run_unpack(&run, sbi, ni->mi.rno, svcn, evcn, svcn,
 				 Add2Ptr(attr, roff),
 				 le32_to_cpu(attr->size) - roff);
@@ -1589,6 +1595,9 @@ int ni_delete_all(struct ntfs_inode *ni)
 		asize = le32_to_cpu(attr->size);
 		roff = le16_to_cpu(attr->nres.run_off);
 
+		if (roff > asize)
+			return -EINVAL;
+
 		/* run==1 means unpack and deallocate. */
 		run_unpack_ex(RUN_DEALLOCATE, sbi, ni->mi.rno, svcn, evcn, svcn,
 			      Add2Ptr(attr, roff), asize - roff);
@@ -2291,6 +2300,11 @@ remove_wof:
 		asize = le32_to_cpu(attr->size);
 		roff = le16_to_cpu(attr->nres.run_off);
 
+		if (roff > asize) {
+			err = -EINVAL;
+			goto out;
+		}
+
 		/*run==1  Means unpack and deallocate. */
 		run_unpack_ex(RUN_DEALLOCATE, sbi, ni->mi.rno, svcn, evcn, svcn,
 			      Add2Ptr(attr, roff), asize - roff);
diff --git a/fs/ntfs3/fslog.c b/fs/ntfs3/fslog.c
index 200e22b7871d..d94c071324a8 100644
--- a/fs/ntfs3/fslog.c
+++ b/fs/ntfs3/fslog.c
@@ -2727,6 +2727,9 @@ static inline bool check_attr(const struct MFT_REC *rec,
 			return false;
 		}
 
+		if (run_off > asize)
+			return false;
+
 		if (run_unpack(NULL, sbi, 0, svcn, evcn, svcn,
 			       Add2Ptr(attr, run_off), asize - run_off) < 0) {
 			return false;
@@ -4769,6 +4772,12 @@ fake_attr:
 		u16 roff = le16_to_cpu(attr->nres.run_off);
 		CLST svcn = le64_to_cpu(attr->nres.svcn);
 
+		if (roff > t32) {
+			kfree(oa->attr);
+			oa->attr = NULL;
+			goto fake_attr;
+		}
+
 		err = run_unpack(&oa->run0, sbi, inode->i_ino, svcn,
 				 le64_to_cpu(attr->nres.evcn), svcn,
 				 Add2Ptr(attr, roff), t32 - roff);
diff --git a/fs/ntfs3/inode.c b/fs/ntfs3/inode.c
index 40b8565815a2..9a4185fa05ad 100644
--- a/fs/ntfs3/inode.c
+++ b/fs/ntfs3/inode.c
@@ -364,6 +364,11 @@ next_attr:
 attr_unpack_run:
 	roff = le16_to_cpu(attr->nres.run_off);
 
+	if (roff > asize) {
+		err = -EINVAL;
+		goto out;
+	}
+
 	t64 = le64_to_cpu(attr->nres.svcn);
 	err = run_unpack_ex(run, sbi, ino, t64, le64_to_cpu(attr->nres.evcn),
 			    t64, Add2Ptr(attr, roff), asize - roff);