Merge: EDAC/thunderx: Fix possible out-of-bounds string access

MR: https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-9/-/merge_requests/3834

JIRA: https://issues.redhat.com/browse/RHEL-26577  
Tested: sanity  
CVE: CVE-2023-52464  
  
commit 475c58e  
Author: Arnd Bergmann <arnd@arndb.de>  
Date:   Wed Nov 22 23:19:53 2023 +0100  
  
    EDAC/thunderx: Fix possible out-of-bounds string access  
  
    Enabling -Wstringop-overflow globally exposes a warning for a common bug  
    in the usage of strncat():  
  
      drivers/edac/thunderx_edac.c: In function 'thunderx_ocx_com_threaded_isr':  
      drivers/edac/thunderx_edac.c:1136:17: error: 'strncat' specified bound 1024 equals destination size [-Werror=stringop-overflow=]  
       1136 |                 strncat(msg, other, OCX_MESSAGE_SIZE);  
            |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
       ...  
       1145 |                                 strncat(msg, other, OCX_MESSAGE_SIZE);  
       ...  
       1150 |                                 strncat(msg, other, OCX_MESSAGE_SIZE);  
  
       ...  
  
    Apparently the author of this driver expected strncat() to behave the  
    way that strlcat() does, which uses the size of the destination buffer  
    as its third argument rather than the length of the source buffer. The  
    result is that there is no check on the size of the allocated buffer.  
  
    Change it to strlcat().  
  
      [ bp: Trim compiler output, fixup commit message. ]  
  
    Fixes: 4100339 ("EDAC, thunderx: Add Cavium ThunderX EDAC driver")  
    Signed-off-by: Arnd Bergmann <arnd@arndb.de>  
    Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>  
    Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>  
    Link: https://lore.kernel.org/r/20231122222007.3199885-1-arnd@kernel.org  
  
Signed-off-by: Aristeu Rozanski <arozansk@redhat.com>

Approved-by: John B. Wyatt IV <jwyatt@redhat.com>
Approved-by: Steve Best <sbest@redhat.com>
Approved-by: David Arcari <darcari@redhat.com>
Approved-by: Prarit Bhargava <prarit@redhat.com>
Approved-by: CKI KWF Bot <cki-ci-bot+kwf-gitlab-com@redhat.com>

Merged-by: Lucas Zampieri <lzampier@redhat.com>

Author: zampierilucas

drivers/edac/thunderx_edac.c

@@ -1133,7 +1133,7 @@ static irqreturn_t thunderx_ocx_com_threaded_isr(int irq, void *irq_id)
 		decode_register(other, OCX_OTHER_SIZE,
 				ocx_com_errors, ctx->reg_com_int);
 
-		strncat(msg, other, OCX_MESSAGE_SIZE);
+		strlcat(msg, other, OCX_MESSAGE_SIZE);
 
 		for (lane = 0; lane < OCX_RX_LANES; lane++)
 			if (ctx->reg_com_int & BIT(lane)) {
@@ -1142,12 +1142,12 @@ static irqreturn_t thunderx_ocx_com_threaded_isr(int irq, void *irq_id)
 					 lane, ctx->reg_lane_int[lane],
 					 lane, ctx->reg_lane_stat11[lane]);
 
-				strncat(msg, other, OCX_MESSAGE_SIZE);
+				strlcat(msg, other, OCX_MESSAGE_SIZE);
 
 				decode_register(other, OCX_OTHER_SIZE,
 						ocx_lane_errors,
 						ctx->reg_lane_int[lane]);
-				strncat(msg, other, OCX_MESSAGE_SIZE);
+				strlcat(msg, other, OCX_MESSAGE_SIZE);
 			}
 
 		if (ctx->reg_com_int & OCX_COM_INT_CE)
@@ -1217,7 +1217,7 @@ static irqreturn_t thunderx_ocx_lnk_threaded_isr(int irq, void *irq_id)
 		decode_register(other, OCX_OTHER_SIZE,
 				ocx_com_link_errors, ctx->reg_com_link_int);
 
-		strncat(msg, other, OCX_MESSAGE_SIZE);
+		strlcat(msg, other, OCX_MESSAGE_SIZE);
 
 		if (ctx->reg_com_link_int & OCX_COM_LINK_INT_UE)
 			edac_device_handle_ue(ocx->edac_dev, 0, 0, msg);
@@ -1896,7 +1896,7 @@ static irqreturn_t thunderx_l2c_threaded_isr(int irq, void *irq_id)
 
 		decode_register(other, L2C_OTHER_SIZE, l2_errors, ctx->reg_int);
 
-		strncat(msg, other, L2C_MESSAGE_SIZE);
+		strlcat(msg, other, L2C_MESSAGE_SIZE);
 
 		if (ctx->reg_int & mask_ue)
 			edac_device_handle_ue(l2c->edac_dev, 0, 0, msg);