6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Enzo Matsumiya ematsumiya@suse.de
[ Upstream commit 998a67b954680f26f3734040aeeed08642d49721 ]
The crypto API, through the scatterlist API, expects input buffers to be in linear memory. We handle this with the cifs_sg_set_buf() helper that converts vmalloc'd memory to their corresponding pages.
However, when we allocate our aead_request buffer (@creq in smb2ops.c::crypt_message()), we do so with kvzalloc(), which possibly puts aead_request->__ctx in vmalloc area.
AEAD algorithm then uses ->__ctx for its private/internal data and operations, and uses sg_set_buf() for such data on a few places.
This works fine as long as @creq falls into kmalloc zone (small requests) or vmalloc'd memory is still within linear range.
Tasks' stacks are vmalloc'd by default (CONFIG_VMAP_STACK=y), so too many tasks will increment the base stacks' addresses to a point where virt_addr_valid(buf) will fail (BUG() in sg_set_buf()) when that happens.
In practice: too many parallel reads and writes on an encrypted mount will trigger this bug.
To fix this, always alloc @creq with kmalloc() instead. Also drop the @sensitive_size variable/arguments since kfree_sensitive() doesn't need it.
Backtrace:
[ 945.272081] ------------[ cut here ]------------ [ 945.272774] kernel BUG at include/linux/scatterlist.h:209! [ 945.273520] Oops: invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC NOPTI [ 945.274412] CPU: 7 UID: 0 PID: 56 Comm: kworker/u33:0 Kdump: loaded Not tainted 6.15.0-lku-11779-g8e9d6efccdd7-dirty #1 PREEMPT(voluntary) [ 945.275736] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-2-gc13ff2cd-prebuilt.qemu.org 04/01/2014 [ 945.276877] Workqueue: writeback wb_workfn (flush-cifs-2) [ 945.277457] RIP: 0010:crypto_gcm_init_common+0x1f9/0x220 [ 945.278018] Code: b0 00 00 00 48 83 c4 08 5b 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc 48 c7 c0 00 00 00 80 48 2b 05 5c 58 e5 00 e9 58 ff ff ff <0f> 0b 0f 0b 0f 0b 0f 0b 0f 0b 0f 0b 48 c7 04 24 01 00 00 00 48 8b [ 945.279992] RSP: 0018:ffffc90000a27360 EFLAGS: 00010246 [ 945.280578] RAX: 0000000000000000 RBX: ffffc90001d85060 RCX: 0000000000000030 [ 945.281376] RDX: 0000000000080000 RSI: 0000000000000000 RDI: ffffc90081d85070 [ 945.282145] RBP: ffffc90001d85010 R08: ffffc90001d85000 R09: 0000000000000000 [ 945.282898] R10: ffffc90001d85090 R11: 0000000000001000 R12: ffffc90001d85070 [ 945.283656] R13: ffff888113522948 R14: ffffc90001d85060 R15: ffffc90001d85010 [ 945.284407] FS: 0000000000000000(0000) GS:ffff8882e66cf000(0000) knlGS:0000000000000000 [ 945.285262] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 945.285884] CR2: 00007fa7ffdd31f4 CR3: 000000010540d000 CR4: 0000000000350ef0 [ 945.286683] Call Trace: [ 945.286952] <TASK> [ 945.287184] ? crypt_message+0x33f/0xad0 [cifs] [ 945.287719] crypto_gcm_encrypt+0x36/0xe0 [ 945.288152] crypt_message+0x54a/0xad0 [cifs] [ 945.288724] smb3_init_transform_rq+0x277/0x300 [cifs] [ 945.289300] smb_send_rqst+0xa3/0x160 [cifs] [ 945.289944] cifs_call_async+0x178/0x340 [cifs] [ 945.290514] ? __pfx_smb2_writev_callback+0x10/0x10 [cifs] [ 945.291177] smb2_async_writev+0x3e3/0x670 [cifs] [ 945.291759] ? find_held_lock+0x32/0x90 [ 945.292212] ? netfs_advance_write+0xf2/0x310 [ 945.292723] netfs_advance_write+0xf2/0x310 [ 945.293210] netfs_write_folio+0x346/0xcc0 [ 945.293689] ? __pfx__raw_spin_unlock_irq+0x10/0x10 [ 945.294250] netfs_writepages+0x117/0x460 [ 945.294724] do_writepages+0xbe/0x170 [ 945.295152] ? find_held_lock+0x32/0x90 [ 945.295600] ? kvm_sched_clock_read+0x11/0x20 [ 945.296103] __writeback_single_inode+0x56/0x4b0 [ 945.296643] writeback_sb_inodes+0x229/0x550 [ 945.297140] __writeback_inodes_wb+0x4c/0xe0 [ 945.297642] wb_writeback+0x2f1/0x3f0 [ 945.298069] wb_workfn+0x300/0x490 [ 945.298472] process_one_work+0x1fe/0x590 [ 945.298949] worker_thread+0x1ce/0x3c0 [ 945.299397] ? __pfx_worker_thread+0x10/0x10 [ 945.299900] kthread+0x119/0x210 [ 945.300285] ? __pfx_kthread+0x10/0x10 [ 945.300729] ret_from_fork+0x119/0x1b0 [ 945.301163] ? __pfx_kthread+0x10/0x10 [ 945.301601] ret_from_fork_asm+0x1a/0x30 [ 945.302055] </TASK>
Fixes: d08089f649a0 ("cifs: Change the I/O paths to use an iterator rather than a page list") Signed-off-by: Enzo Matsumiya ematsumiya@suse.de Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/smb/client/smb2ops.c | 17 ++++++----------- 1 file changed, 6 insertions(+), 11 deletions(-)
diff --git a/fs/smb/client/smb2ops.c b/fs/smb/client/smb2ops.c index b74f769047394..ee6a6ba13f89c 100644 --- a/fs/smb/client/smb2ops.c +++ b/fs/smb/client/smb2ops.c @@ -4152,7 +4152,7 @@ fill_transform_hdr(struct smb2_transform_hdr *tr_hdr, unsigned int orig_len, static void *smb2_aead_req_alloc(struct crypto_aead *tfm, const struct smb_rqst *rqst, int num_rqst, const u8 *sig, u8 **iv, struct aead_request **req, struct sg_table *sgt, - unsigned int *num_sgs, size_t *sensitive_size) + unsigned int *num_sgs) { unsigned int req_size = sizeof(**req) + crypto_aead_reqsize(tfm); unsigned int iv_size = crypto_aead_ivsize(tfm); @@ -4169,9 +4169,8 @@ static void *smb2_aead_req_alloc(struct crypto_aead *tfm, const struct smb_rqst len += req_size; len = ALIGN(len, __alignof__(struct scatterlist)); len += array_size(*num_sgs, sizeof(struct scatterlist)); - *sensitive_size = len;
- p = kvzalloc(len, GFP_NOFS); + p = kzalloc(len, GFP_NOFS); if (!p) return ERR_PTR(-ENOMEM);
@@ -4185,16 +4184,14 @@ static void *smb2_aead_req_alloc(struct crypto_aead *tfm, const struct smb_rqst
static void *smb2_get_aead_req(struct crypto_aead *tfm, struct smb_rqst *rqst, int num_rqst, const u8 *sig, u8 **iv, - struct aead_request **req, struct scatterlist **sgl, - size_t *sensitive_size) + struct aead_request **req, struct scatterlist **sgl) { struct sg_table sgtable = {}; unsigned int skip, num_sgs, i, j; ssize_t rc; void *p;
- p = smb2_aead_req_alloc(tfm, rqst, num_rqst, sig, iv, req, &sgtable, - &num_sgs, sensitive_size); + p = smb2_aead_req_alloc(tfm, rqst, num_rqst, sig, iv, req, &sgtable, &num_sgs); if (IS_ERR(p)) return ERR_CAST(p);
@@ -4283,7 +4280,6 @@ crypt_message(struct TCP_Server_Info *server, int num_rqst, DECLARE_CRYPTO_WAIT(wait); unsigned int crypt_len = le32_to_cpu(tr_hdr->OriginalMessageSize); void *creq; - size_t sensitive_size;
rc = smb2_get_enc_key(server, le64_to_cpu(tr_hdr->SessionId), enc, key); if (rc) { @@ -4309,8 +4305,7 @@ crypt_message(struct TCP_Server_Info *server, int num_rqst, return rc; }
- creq = smb2_get_aead_req(tfm, rqst, num_rqst, sign, &iv, &req, &sg, - &sensitive_size); + creq = smb2_get_aead_req(tfm, rqst, num_rqst, sign, &iv, &req, &sg); if (IS_ERR(creq)) return PTR_ERR(creq);
@@ -4340,7 +4335,7 @@ crypt_message(struct TCP_Server_Info *server, int num_rqst, if (!rc && enc) memcpy(&tr_hdr->Signature, sign, SMB2_SIGNATURE_SIZE);
- kvfree_sensitive(creq, sensitive_size); + kfree_sensitive(creq); return rc; }