lwn.git/net/sctp/stream.c, branch docs-next

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

sctp: Constify struct sctp_sched_ops

2025-10-29T00:50:55+00:00

'struct sctp_sched_ops' is not modified in these drivers. Constifying this structure moves some data to a read-only section, so increases overall security, especially when the structure holds some function pointers. On a x86_64, with allmodconfig, as an example: Before: ====== text data bss dec hex filename 8019 568 0 8587 218b net/sctp/stream_sched_fc.o After: ===== text data bss dec hex filename 8275 312 0 8587 218b net/sctp/stream_sched_fc.o Signed-off-by: Christophe JAILLET Link: https://patch.msgid.link/dce03527eb7b7cc8a3c26d5cdac12bafe3350135.1761377890.git.christophe.jaillet@wanadoo.fr Signed-off-by: Jakub Kicinski

treewide: Switch/rename to timer_delete[_sync]()

2025-04-05T08:30:12+00:00

timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree over and remove the historical wrapper inlines. Conversion was done with coccinelle plus manual fixups where necessary. Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar

sctp: Fix undefined behavior in left shift operation

2025-02-20T02:55:40+00:00

According to the C11 standard (ISO/IEC 9899:2011, 6.5.7): "If E1 has a signed type and E1 x 2^E2 is not representable in the result type, the behavior is undefined." Shifting 1 << 31 causes signed integer overflow, which leads to undefined behavior. Fix this by explicitly using '1U << 31' to ensure the shift operates on an unsigned type, avoiding undefined behavior. Signed-off-by: Yu-Chun Lin Link: https://patch.msgid.link/20250218081217.3468369-1-eleanor15x@gmail.com Signed-off-by: Jakub Kicinski

sctp: delete the nested flexible array params

2023-04-21T07:19:29+00:00

This patch deletes the flexible-array params[] from the structure sctp_inithdr, sctp_addiphdr and sctp_reconf_chunk to avoid some sparse warnings: # make C=2 CF="-Wflexible-array-nested" M=./net/sctp/ net/sctp/input.c: note: in included file (through include/net/sctp/structs.h, include/net/sctp/sctp.h): ./include/linux/sctp.h:278:29: warning: nested flexible array ./include/linux/sctp.h:675:30: warning: nested flexible array This warning is reported if a structure having a flexible array member is included by other structures. Signed-off-by: Xin Long Signed-off-by: David S. Miller

sctp: fix memory leak in sctp_stream_outq_migrate()

2022-11-29T16:30:50+00:00

When sctp_stream_outq_migrate() is called to release stream out resources, the memory pointed to by prio_head in stream out is not released. The memory leak information is as follows: unreferenced object 0xffff88801fe79f80 (size 64): comm "sctp_repo", pid 7957, jiffies 4294951704 (age 36.480s) hex dump (first 32 bytes): 80 9f e7 1f 80 88 ff ff 80 9f e7 1f 80 88 ff ff ................ 90 9f e7 1f 80 88 ff ff 90 9f e7 1f 80 88 ff ff ................ backtrace: [] kmalloc_trace+0x26/0x60 [] sctp_sched_prio_set+0x4cc/0x770 [] sctp_stream_init_ext+0xd2/0x1b0 [] sctp_sendmsg_to_asoc+0x1614/0x1a30 [] sctp_sendmsg+0xda1/0x1ef0 [] inet_sendmsg+0x9d/0xe0 [] sock_sendmsg+0xd3/0x120 [] __sys_sendto+0x23a/0x340 [] __x64_sys_sendto+0xe1/0x1b0 [] do_syscall_64+0x39/0xb0 [] entry_SYSCALL_64_after_hwframe+0x63/0xcd Link: https://syzkaller.appspot.com/bug?exrid=29c402e56c4760763cc0 Fixes: 637784ade221 ("sctp: introduce priority based stream scheduler") Reported-by: syzbot+29c402e56c4760763cc0@syzkaller.appspotmail.com Signed-off-by: Zhengchao Shao Reviewed-by: Xin Long Link: https://lore.kernel.org/r/20221126031720.378562-1-shaozhengchao@huawei.com Signed-off-by: Jakub Kicinski

sctp: leave the err path free in sctp_stream_init to sctp_stream_free

2022-07-28T01:23:22+00:00

A NULL pointer dereference was reported by Wei Chen: BUG: kernel NULL pointer dereference, address: 0000000000000000 RIP: 0010:__list_del_entry_valid+0x26/0x80 Call Trace: sctp_sched_dequeue_common+0x1c/0x90 sctp_sched_prio_dequeue+0x67/0x80 __sctp_outq_teardown+0x299/0x380 sctp_outq_free+0x15/0x20 sctp_association_free+0xc3/0x440 sctp_do_sm+0x1ca7/0x2210 sctp_assoc_bh_rcv+0x1f6/0x340 This happens when calling sctp_sendmsg without connecting to server first. In this case, a data chunk already queues up in send queue of client side when processing the INIT_ACK from server in sctp_process_init() where it calls sctp_stream_init() to alloc stream_in. If it fails to alloc stream_in all stream_out will be freed in sctp_stream_init's err path. Then in the asoc freeing it will crash when dequeuing this data chunk as stream_out is missing. As we can't free stream out before dequeuing all data from send queue, and this patch is to fix it by moving the err path stream_out/in freeing in sctp_stream_init() to sctp_stream_free() which is eventually called when freeing the asoc in sctp_association_free(). This fix also makes the code in sctp_process_init() more clear. Note that in sctp_association_init() when it fails in sctp_stream_init(), sctp_association_free() will not be called, and in that case it should go to 'stream_free' err path to free stream instead of 'fail_init'. Fixes: 5bbbbe32a431 ("sctp: introduce stream scheduler foundations") Reported-by: Wei Chen Signed-off-by: Xin Long Link: https://lore.kernel.org/r/831a3dc100c4908ff76e5bcc363be97f2778bc0b.1658787066.git.lucien.xin@gmail.com Signed-off-by: Jakub Kicinski

net: sctp: Fix negotiation of the number of data streams.

2020-08-20T23:37:37+00:00

The number of output and input streams was never being reduced, eg when processing received INIT or INIT_ACK chunks. The effect is that DATA chunks can be sent with invalid stream ids and then discarded by the remote system. Fixes: 2075e50caf5ea ("sctp: convert to genradix") Signed-off-by: David Laight Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

sctp: shrink stream outq when fails to do addstream reconf

2020-07-23T01:00:12+00:00

When adding a stream with stream reconf, the new stream firstly is in CLOSED state but new out chunks can still be enqueued. Then once gets the confirmation from the peer, the state will change to OPEN. However, if the peer denies, it needs to roll back the stream. But when doing that, it only sets the stream outcnt back, and the chunks already in the new stream don't get purged. It caused these chunks can still be dequeued in sctp_outq_dequeue_data(). As its stream is still in CLOSE, the chunk will be enqueued to the head again by sctp_outq_head_data(). This chunk will never be sent out, and the chunks after it can never be dequeued. The assoc will be 'hung' in a dead loop of sending this chunk. To fix it, this patch is to purge these chunks already in the new stream by calling sctp_stream_shrink_out() when failing to do the addstream reconf. Fixes: 11ae76e67a17 ("sctp: implement receiver-side procedures for the Reconf Response Parameter") Reported-by: Ying Xu Signed-off-by: Xin Long Signed-off-by: David S. Miller